Archive for category syncro specific repairs

Vanagon – jury rigged fix for deceased cat

This post might get me some guff, but please have patience, I will get a new cat. The catalytic converter on my van is old, very old. Recently I’ve suspected it really was a converter in name only. I took it off today and it was empty. All the rare earth metals and ceramic had blown out through my stainless muffler. Ok, so now what? I had the shell in my hands and I decided to do a little experiment before i hunted up a new cat.

I had this resonator muffler thingy hanging around the mess I call a workshop. It is a little longer than the cat but I thought I could slap it in place and  see how it effects the sound of the exhaust. Ok, here goes..

The resonator, 2″ outlet/inlet. I scrounged a 3 bolt flange and cleaned it up on the lathe. Bored it out a tad so it would fit on the pipe.

IMG_3029

You see? Pipe set into the flange.

IMG_3030

And positioned not quite all the way through.

IMG_3031

 

While I was at the lathe I necked down a nut to act as a threaded bung for the O2 sensor. Man, I just can’t recall the size of that nut right now.

IMG_3032

Tacked the flange to the pipe.

IMG_3033

Then a mostly autogenous weld inside.

IMG_3034

If you squint you could imagine that hole was roundish.

IMG_3036

Necked down nut pushed in hole.

IMG_3037

And a bit of a heavy handed weld.

IMG_3038

Two slits on the other end (tubing fits over the tubing inlet of the muffler. The slits will let the muffler clamp squeeze the assembly tight)

IMG_3039

During installation my new lover was pestering me. For the last few weeks this goose has decided I am something special. I really don’t know what is going on with her.

IMG_3040

I had to slide the muffler over a bit to get the resonator installed. It does look a bit funny, I admit. And did it change the exhaust sound? Yes it did, it is a bit quieter, with a hint of raspy with quick throttle off.

IMG_3043

 

9 Comments

Vanagon – propshaft skid plate of sorts

Edit: I wrote that I used 10-24 insets and screws. I made a mistake, they are actually 1/4-20.

It seems like an age since I have posted on the blog, I guess I’ve been in the doldrums. No major van projects completed, the bumper build has been on a bit of a hiatus as I don’t want to be doing the steel fabrication part (trailer hitch) at work when we are doing aluminum work. But i have to get back on that horse soon or else I never will. I have done a little  work on it however, I cut off the end caps and slimmed them down some. A trial fit of the originals showed that they were a bit clunky.

Even being in the doldrums, or maybe it was the horse latitudes, I have managed to do a couple of little things and this post is about something I did this afternoon. I had a bit of 3/16″ aluminum plate (5052 alloy) earmarked for propshaft protection. Oh I know what you are thinking, that’s not beefy enough is it? Perhaps not, if you want rock crawling type protection. But I’m just looking for something to protect the propshaft from flying sticks and stones and the occasional scrape over gravel.

I cut the plate to size (and by the way the two propshaft rails are not parallel, they taper in about 3/4″ towards the front) so that there would be a 3/4″ projection on each side of the stock skid rails. I want that projection so that I can attach (later) some more plate to enclose the space between the skid rails and the frame rails. I drilled 1/8″ pilot holes, 10 places, locations for machine screws to attach the plate to the skid rails.

IMG_2826

Then I clamped the plate to the rails and drilled 1/8″ holes in the rails using the previously drilled holes as a guide.

IMG_2827

I removed the plate then enlarged the 1/8″ holes to accept threaded inserts. I bought this cheap insert tool at Princess Auto, back in the hazy days of summer. It came with a selection of inserts. I’m using the 10-24 inserts here. You screw the insert onto a threaded boss on the tool, insert the insert (!) into the hole and squeeze the handle. A couple of broken blood vessels later the insert is secured. Tool with insert in hole and an insert itself shown in this pic.

IMG_2828

How it looks after insertion.

IMG_2829

After a few more ruptured blood vessels all the inserts were installed. Oh I did spray some high zinc paint in the drilled holes before insertion of the inserts. Originally I had thought of counter sunk machine screws to attach the plate, but you know how it is with counter sunk screws, you have to get things perfectly aligned. I opted instead for these rather nice large (almost a truss head) headed stainless screws.

IMG_2830

I have a notion to weld some braces on the back side of the plate just to beef it up a bit more. But then again I’m only using 10-24  1/4-20 screws to hold the darned thing on.

I’m happy with the result, and happy to be back blogging about the arcane things I do for fun.

4 Comments

Vanagon – Temp II sensor replacement

A rather thin post but since I took pictures I might as well post them up. On our last camping trip the van had a strange missing/bucking/bogging problem. This has happened twice before, always in summer, and always cured by a fill up of gas. So I’m leaning towards the “bad gas” explanation but I’m not ruling out other causes. I have checked and re-adjusted the throttle position switch and perhaps I should take the throttle body off again, take some pics and do a post about that. The next on my list was the temp II sensor. This is the sensor that tells the computer what the coolant temperature is. Not to be confused with the dash water temp gauge sensor. The connector to my sensor was broken and I’ve always wondered if it was making a good connection all the time. I thought that if I was going to install a new connector why not put in a new sensor too. Dave, from Dave’s Automotive in nearby Sidney BC (great guy) found me a connector and wired in a pair of pigtails. So off we go then, with the install.

sender

 

The sender takes a 19mm wrench, but I didn’t pull it until I spliced in the new connector.

IMG_2473

 

I took a couple of resistance measurements from the new sender, one in the evening and one in the morning. Pathetic eh? 🙂

I used crimp style butt connectors and heat shrink to make the splice. Not shown in above pic are the two smaller bits of heat shrink to go over the individual butt connectors.

Here’s a shot of the damaged connector.

IMG_2472

 

And replacement one spliced in. You don’t loose much coolant at all if you are quick with the sender swap.

IMG_2474

 

New connector and sender in place. The extra wire (and it does help to have extra wire when you splice in situ) is taken up to some degree by one turn and a zip tie on the crossing.

 

IMG_2476

 

And boy oh boy, the new sender really has transformed the van. No, I lie. No noticeable difference. But then again my strange bucking/bogging problem occurs every 18 months or so…h

6 Comments

Vanagon – Syncro propshaft angle measurements… again

Warning: what follows is a very long-winded and tedious description of my further exploration of propshaft U-joint angles. Experienced and knowledgable readers, please, cut me some slack and refrain from face palming at my antics.

Being quite adept at re-inventing the wheel, I’m now re-inventing measuring propshaft angles. If you are a regular reader of this blog, and man it feels good to write that (evidence of my amusement with small things), you know I have spent some time exploring the flange angles of the transmission and front differential (my previous attempts, onetwothree.). I came cold to this subject, never having to deal with anything like this before, and Bentley has nothing to say about the matter. So perhaps I could be forgiven for my naive approach to the matter. Perhaps, but really no, I should have cut through the crap right away.

A little background

The transmission is connected to the front differential via a propshaft. On each end of the propshaft are U-joints (single cardan joints) that allow a little bit of misalignment between and movement of the transmission and the front differential. Now the problem with U-joints is that they do not transfer the rotational motion of the propshaft perfectly smoothly, ie. without pulsation, especially when the U-joint angles are greater than 3 or 4  degrees  and also if the angles differ from each other more than 1 degree (more on those angles later). Most of you know this, and also about the correct phasing of the the U-joints on each end of the shaft, but I do recommend having a look at this document from Spicer that explains all:

Spicer info on driveshaft install, angles, vibrations, etc. (pdf). 

And this Spicer document on measuring angles succinctly describes using Spicer’s angle finder doodad.

Spicer info on measuring angles

One subject not really covered well in that document is compound angles. That is when there is mis-alignment is in 2 planes, ie horizontal and vertical. I’ll go into that at the end of this post.

Over time I became dissatisfied with my last attempt at measuring flange angles with my laser tool. Don’t get me wrong, I think it is a pretty neat way of measuring the flange angles and it measures both in vertical and horizontal planes. But you need to have the propshaft removed.
After some email exchanges with J. Slider, I reconsidered the protractor/angle finder method of measuring flange angles. I wasn’t very happy with the results I got when I tried this method a while back. I was unable to get consistent results measuring the flange angles with my propshaft removed. It came down to getting the electronic angle finder positioned correctly on the transmission and front differential flanges. But Jon’s argument for the angle finder method convinced me to try again.
I was sidetracked by an idea of a false propshaft jig thing. I reasoned that if I could make a jig that mimicked the propshaft but was constructed so that flange angles could be more easily measured it would be a good thing. I even thought of making a false propshaft with fixed, *ideal* flange angles that I could use to adjust the transmission and front diff. mounts. I still think this would be a worthwhile tool to make for those folk who install propshafts in vanagons.

– This flurry of innovative thinking (ha!) coincided with me removing my propshaft and having it checked for balance by Royce at Island Torque Converter & Driveshaft. Royce is THE guy to take your propshaft to for repair/balancing. He does good work, prices are very reasonable, and he is willing to work with you in solving driveline issues. Local (Vancouver Island) phone # is 250 388 4248 –

Royce and I talked about the syncro propshaft and about making a shaft with Rzeppa type CV joints. That discussion is another story but when I was Googling around with the idea of Rzeppa joints on shaft I came across a document describing the install of a marine, Rzeppa jointed, short prop shaft. In that document (you can see it here) the use of jigs that I described above is detailed. Foiled again. Is it always to be thus? Are all my ideas “a day late and a dollar short”?

I took my propshaft to Royce around the 15th of December and got it back the next day. But with one thing and another I did not get the shaft re-installed in the van until the 9th of January. During that time, when I was not working, eating, drinking, Xmas shopping, sleeping, putting up then taking down Xmas trees, etc, etc, I was mulling over the propshaft jig idea.

Too much mulling, not enough action. So I ended up going back to the protractor/angle finder on the installed propshaft method. You’ve seen this before, and it is described in the Spicer document, I just added a very minor twist.

Home-made tool

I mentioned at the beginning how I was never happy with the measuring propshaft angles with the angle finder because I could not get a good surface to place the gauge on. So I decided to do what others have done and use the ends of the U-joint bearing cup as the reference surface. That meant making a little tool.

A bit of scrap steel from some failed project.

IMG_1818

Turned it down and machined a recess in one end to accept a rare earth magnet.

IMG_1832

Fits in fine, held in firmly by magnetism and Locktite.

IMG_1833

The magnet face is recessed from the rim of the tool by a gnat’s crotchet.

IMG_1834

Here is my other propshaft, to be used for trial fitting. Big note here, ideally the circlip should be removed so that the tool can lie directly on bearing cup. But I reasoned that these circlips would be lying parallel to the bearing cups. Any dirt or damage to the circlips would screw things up.

IMG_1822

Tool on the joint.

IMG_1831

Angle finder on tool, held by magnets on side of angle finder. It looks like the angle finder is resting on flange, but it is not.

IMG_1827

Angle finder on end of tool. I was not sure at this time which way would be better.

IMG_1826

A bit of channel to provide a base to measure the propshaft angle.

IMG_1828

Trying out the tool

Ok then, out to the van. First I had to install the re-balanced shaft (not the red one pictured above). I jacked up one side of van and supported on blocks. Wheels off the ground.

IMG_1835

Small aside, I finally replaced the 1/2″ bolt used to hold the jack adapter onto the jack with a gated pin thing.

IMG_1836

After the propshaft was installed (please note, I do insist on loosening the 3 bolts that go through the rubber mounts on the front diff. when I am installing/removing the shaft) I took the van off the blocks, released the parking brake and chocks, then crawled under to have a go at measuring angles. First I moved the van back and forth so that a bearing cup on the U-joint yoke that is attached to the flange was pointing directly down. I gave it a bit of a scrub then attached the tool.

IMG_1837

See how the angle finder is a little askew on the shaft of the tool? This affects the angle measurement. It was hard to get the angle finder aligned true to the shaft when I was scrooched up under the van. Would have been much easier if the van was on a lift. But I persisted, went on to measure the propshaft angle.

IMG_1838

And see how I do not have the angle finder aligned along the channel? It is askew too, and this affect the readinghh. And then on to the front diff. end of shaft.

IMG_1840

Repeated the procedure a few times.

IMG_1842

A bit better alignment on channel.

IMG_1843

Again on the front.

IMG_1847

And on the rear.

IMG_1848

But I was not happy with the procedure, I was not sure of confident of the accuracy of the readings.

V-block modification and engine carrier adjustment

I tried a nice little Starrett V-block on the tool. I thought it might help me to keep the angle finder aligned along the long axis of the tool.

IMG_1855

I was running out of afternoon and I wanted to try something more. I knew from previous measuring that the transmission flange pointed down more than the front diff flange. I wanted to reduce that angle, but I also new that there really is no easy way to do that. The transmission mounts towards the front of the transmission are really awkward to get at and fiddle with (especially when you don’t have a lift), so that leaves the engine mounts at the rear. But the arrangement/relative placements of the mounts means that it takes a fair bit of movement at the engine mount to effect a little movement at the transmission flange. Perhaps these data from R. Jones illustrates this (front diff. data included).

“4) I measured the distance between the flanges and the
mounting points, tranny and front diff, and worked the ratios.
Using washers, here’s what one can do:

a) raise front mount, front diff, lower flange.
1 unit raising gets 0.83 units lowering the flange.

b) raise rear mounts, front diff, raise flange.
1 unit raising gets 1.2 units at the flange.
This is the wrong way however.

c) lower tranny at front mounts, lowering flange.
1 unit at mount gets 1.25 units at flange.
Again, this is the wrong direction.

d) lower engine at carrier attachment to frame,
raise flange.  1 unit at engine gets 0.25 units
at flange.  Hardly worth it.”

I wanted to try “d”. So I supported the engine carrier (“moustache bar”) with a jack and removed the 2 bolts, each side, that hold the bar to the van frame. I had no time to record flange angles vs. amount of lowering of rear carrier, and I decided to try 5/16″ as the distance lowered. Handy number, I had some 5/16″ aluminum plate scrap on hand. On the top side of the flange on the van body that the carrier mounts to there is a steel backing plate. I used that plate to lay out the bolts holes in the aluminum spacer.

IMG_1849

Holes drilled.

IMG_1850

And spacer inserted. I used longer bolts. Damn mudflap mounting strut interfered.

IMG_1851

Maybe you can tell, the light was fading fast. I got back under and measured angles, using the V-block innovation.

Transmission flange angle.

IMG_1853

Front diff. flange angle.

IMG_1854

By now it was dark and I was cold. I left things as they  as far as I got to: rear engine mount dropped by 5/16″.

It now occurs to me that I have not mentioned another little thing I did (a year ago) to resolve flange angle difference – I removed the topmost metal washers of the two rearmost mounts of the front diff. This did drop the flange of the front diff. a bit – I reasoned back then, that if I could not reduce the flange angle of the transmission the I would increase the flange angle of the front diff. I hoped that matching the flange angles did more to reduce vibrations than trying to get both flange angles below 4 degrees. I’ll clear this up at the end, I know this story is getting very muddy right now.

Road test

Okee dokee, I drove the van for the next couple of days. Felt pretty smooth, my 50-60 kph minor vibe has gone. I do have the very, very slightest vibration especially when accelerating, at around 40-45 kph. But I noticed this when the propshaft was removed so I am discounting that it has anything to do with the shaft.

I was pretty happy with this. I’d say that the re-balanced shaft is sweet.

Further modification to the tool

But I still wanted to measure the flange angles with somewhat more confidence. I cut a chunk of 1.5″ X 0.25″ hot rolled flat stock, drilled a hole, and screwed it (1/4 “- 20) to the end of the little tool. I checked it for square, was good. Now I had a better reference surface to place the angle finder against, and I could line up the long axis of the plate with the propshaft.

IMG_1857

Here it is on the transmission end of the shaft. It is much easier now to use the angle finder to determine that the tool is pointing straight down, and the  plate can be lined up fore and aft with the propshaft. Those two things are important in measuring the true angle of the flange. Remember, the tool is on the bearing cup in the flange yoke of the U-joint. That means it projects the angle that the transmission flange is making with respect to the propshaft.

IMG_1858

One way of doing it. The angle finder was inline with the bottom plate of the tool. This was not a recorded measurement, I had not adjusted propshaft so that tool is pointing straight down.

IMG_1859

I found that having the angle finder in this position was the best. The magnets in the angle finder held it to the vertical shaft, but still allowed it to be aligned to the bottom plate.

IMG_1864

A another measurement (using the channel) of the propshaft angle.

IMG_1865

And a good measurement of the front diff flange angle.

IMG_1866

Results

Ok, I was getting more consistent measurements, now to look at some of the data. Remember, we are measuring relative angles here, not absolute angles. For example, the propshaft could be pointing down towards the front at 1.30 degrees, or at 2.85 degrees depending (apart from measuring errors) on the level of the van (ie just exactly where it was parked in my driveway). The sketch below summarizes my results. The top cartoon represents the situation right after I installed the propshaft. Let’s go over it, bit by bit.

The transmission flange (and the transmission and engine) is pointing down towards the front of the van at 5.5o degrees. The propshaft is also pointing down in the same direction, but only at 1.30 degrees. If we subtract the propshaft angle from the transmission flange angle we will find that U-joint operating angle, and it is 4.20 degrees. Remember: if the angles are in the same direction then subtract the smaller angle from the larger angle to find the joint operating angle.

proshaft angle-1

At the other end the front diff. is pointing down towards the rear of the vehicle, in the opposite direction of the propshaft angle. I added a negative sign to that measurement to remind me of its different direction. So in this situation the absolute value of the front diff. measured angle, -2.50 degrees, is added to the propshaft angle of 1.30 degrees. Result is a 3.80 degree joint operating angle. Remember: if the angles are in opposite directions then add the absolute values of the two angles to find the joint operating angle.

As clumsy as those two paragraphs are, I hope you get the idea of how the operating angles are arrived at. Of course with an electronic angle finder I could have zeroed on the propshaft angle and read the working angles directly. But I thought it would be clearer to me and to you if I did it explicitly.

Now the measurements after I installed the 5/16″ (8 mm) shim back at the engine carrier.

proshaft angle-2

And finally, the same set up but this time more accurately measured (bottom plate added to my home-made tool).

proshaft angle-3

I am fairly confident in this last measurement. Even if it is not perfect, I am sure the two flange angles are within 0.2 degrees of each other, though I do wish that the operating angles were less.

Compound angles

At the beginning of this post I said I was going to discuss compound angles, so here we go. The above sketches show angles in a vertical plane, but you can imagine that the same thing could be going on if you could look down from above. The transmission and front diff. could be laterally mis-aligned. What is interesting, is the combined effect of both lateral and vertical misalignment. The Aquadrive document I linked to previously has some good information on compound angles.

The accurate formula for calculating the compound angle is:

2013-01-13 09.05.48 am

Lovely stuff eh? Shall we do an example? (and please God, let me do the math correctly).

Let’s say we have a vertical flange angle (ie the kind we have been measuring ) of 4.1 degrees. And let’s say the lateral angle is 1.0 degrees. First step is to find the tangents of those angles.

tan 4.1 = 0.0716808913

tan 1.0 = 0.0174550649

we square both of these numbers and add them together:

(0.0716808913)^2 + (0.0174550649)^2

= 0.0051381502 + 3.0467929066e-4

= 0.0054428295

then we take the square root of that number and we get:

0.0737755345

now we take the arctan (inverse tangent) of that number to find the answer, our compound angle:

compound angle = arctan (0.0737755345)

compound angle = 4.22 degrees

(Another example – 4 degree vertical angle and a 2 degree lateral angle, then the effective compound angle would be 4.47 degrees)

Not much of a difference, 4.22 degree compound angle compared to 4.10 degree vertical angle. So should we worry about lateral misalignment? Well, in the stock set up there is some room to laterally adjust both the transmission and the front diff. The old trick of leaving the front diff. mount bolts a little loose after installing the propshaft, then driving the van for a few miles before tightening those bolts, probably serves to reduce or eliminate lateral mis-alignment. But with vans that have non-stock engines/engine carriers installed, then there is a very good chance of having the engine and transmission laterally askew enough for that trick not to be enough.

Conclusions:

  •  no matter what you read or hear, in the vanagon syncro the propshaft operating angles should be 4 degrees or less (but not zero degrees). Ideally they should be less than 3 degrees. Unfortunately there is no easy way to adjust the front diff and transmission vertical flange angles to achieve this. On vans with engine conversions and modified engine carriers, careful attention MUST be paid to the transmission angle.
  • U-joint operating angles should be the same or within 0.2 degrees of each other.
  • measuring the angles can be done fairly accurately with home-made tools. A smart phone with an inclinometer app could be used instead of my little electronic angle finder. But some sort of adapter between the joint and the phone must be used to ensure accurate and consistent readings.
  •  lateral misalignment of the transmission and resulting compound angles are very important to check and deal with if a non-stock engine has been installed. Remember that the angles combine and result in an effective angle greater than any one of the individual angles.
  • Your man on Vancouver Island for propshaft balancing is Royce at Island Torque Converter & Driveshaft. Phone # 250 388 4248

,

4 Comments

Vanagon syncro – front spring swap and radius arm bushing replacement

The other thing I did recently was swap in a pair of front springs from my old ’82 westy into the front of my ’86 syncro. You know that that suspension set up is different between the 2wd and syncro vanagons, the syncro has a spring perch on the shock absorber and uses (generally) shorter springs than the 2wd vans. I compared the spring lengths of the ’82 diesel westy and my ’86 syncro in this blog post, and in this post. This particular 2wd spring is about 20 mm longer than the syncro spring, but the wire diameter (approx 16.6 mm) and number of turns (8) are the same. The spring rate, if I have identified the 2wd spring correctly, is according to the IG16 wiki 80 N/mm. It is the same spring rate as the syncro springs I have. It seems only one spring type was installed in North American market syncro tintops and westies.

I’ve not been pleased with the amount of  “springing” in the van. With the westy conversion it must be a bit heavier than it was as a tintop, and I find that the van scrapes the spare tire clamshell on the ground when I’m negotiating ditches, trenches etc on logging roads. Friend Simon would add that my excessive bulk is not helping things. The distance between the front fender lip and the wheel centre was about 18.25″. I would like it to be at least 19″, but not more than 19.5″. At the back it is trivial to add some shims to raise things, and I did do that (rear measurement 19″). That shimming made the front end look even lower.

I’m not ready to dive into the hyperbole ridden and expensive world of aftermarket springs and shocks, and one must consider springs and shocks together. Increasing the spring rate does require increasing the dampening abilities of the shock.

Originally thought that I would add a shim to the top of the spring, but then I decided to give the spring swap a go. I did not know whether the “no compressor spring removal” technique would work with longer springs so I bought a rather cheap spring compressor from Princess Auto. Spring compressors give me the willies, I feel like I am on a bomb disposal mission when I use them.

Upper A-arm disconnected from upper ball joint, you’d think there is enough room to get the compressors in.

IMG_1804

Nope, not enough compression with this set up.

IMG_1806

Ditto here. The hex area at top of compressor does not allow you to get a grab on a higher coil, plus at the other end, the screws are too long and interfere with the axle shaft. I wasted about an hour mucking around with the compressors, I finally gave up. I could have cut the screws down, but I was of two minds about that. Was it worth wasting more time trying to get them to work or try and return them to the store?

IMG_1805

So I went back to the no compressor method. Radius arm arm was removed, sway bar drop link disconnected, nut and rubber bushing removed from top of shock, and the lower control arm carefully lowered so that the spring and shock could be pulled out to the side and the spring removed. One thing though, I had installed a westy swivel seat base on the passenger side this summer. So I had to make a hole in the base to access the plug that, once removed,  allows you to put insert a tool to guide the shock back up into the shock tower during re-install.

IMG_1809

So, I got the passenger side spring installed (radius arm bushings on that side done too) on New Year’s day. With one spring installed, and before driving to settle things in, I got a 19.5″ measurement from hub centre to fender lip. I like that look, it is as high as I want to, or should go. A couple of days later I got the other side done and the hub to fender height settled in at 19 1/8″. Driving the van felt a little different, I could tell the front was higher (yes, I really could detect the change), there was no difference in how the van dipped or raised over bumps. Mind you this was only driving over the lumpy roads in North Saanich, no logging road travel done yet.

IMG_1810

Now some shameful pics of the dreadful state of my radius arm bushings…

New bushings and radius arm. Note the shiny spacer I made over a year ago.

IMG_1808

Old and new.

IMG_1807

“By Timothy, what a difference”

IMG_1812

“Shocking!”

IMG_1813

Conclusions?

Well I think the spring swap was worth the effort but I will add a teeny tiny little spacer (about 1/4″ thick) to bring it up to 19.5″ hub to fender lip measurement. As to the radius arm bushings, I don’t think any further comments are needed.

15 Comments

Vanagon – Syncro propshaft bushing – 6 month update

Today, after the latest storm blew over and rain stopped, I got under the van and pulled the propshaft. “Again?” I hear you say, yes again. This time prompted by a few things:

1. I still have the slightest bit of propshaft vibe around 55-60 kph

2: J. Slider and I have been having an email correspondence discussing measuring flange angles on shaft. I want to re-do my measurements after the exchange of ideas we had.

3. I have a jig in mind to set flange angles.

So I pulled the bugger and it will be taken to driveline guy to check balance. So seeing as I have it off, I thought I’d check how the internal Delrin bushings I made back in June are holding up (the original posts describing how I made them, part one and part two). Well, the fit of the shaft in the bushings is as tight as it was when first installed. I tried to get some pics, in one of them, you can make out the split bushing still intact at the end of the bore. I have to admit that I worried that the split bushing wouldn’t last, I’m pleased that the Delrin held up.

IMG_1796

IMG_1797

IMG_1798

,

Leave a comment

Vanagon – front brake fandango

I hope the story that follows will help someone be less stupid than I have been the last 2 days. No, that doesn’t sound right, no one would have been as dim as me notwithstanding.

Story starts with passengers complaining of squeaks from front left brake/wheel. Further development was noticing a clunk/rattle when going downhill on washboard/rough roads this last weekend. Noise seemed to be affected by brake application. Signs say examine front end and brakes. So I do that, could not find any loose or broken suspension components but did find that my brake pads were getting thin, and one pad on pass. side had a broken spring. So here is where I should have sat down and thought things through more. New pads are a good idea, but what about new rotors too? I did measure old rotors, they were within wear spec, so ADD boy here rushes out and buys some expensive Pagid pads and leaves rotors alone.

Quite a difference in thickness between old and new eh? Hint: that should have triggered a response in my brain other than “gee, look at the thickness difference”. Oh and another oversight, I mentioned that I measured the old rotor thickness, doing that I did note the ridges on the rotor (peripheral and internal) where the pads do not touch. I didn’t think that would be an issue, ha!

So I popped in the new pads. Bentley describes the procedure well, but did I do a careful reading? No, I didn’t. I removed both bolts from the caliper slider and removed slider to install pads. That is NOT how to do it. There are bold warnings not to re-use those slider bolts and the new pads came with just 2 new bolts (with pre-applied thread locker). I was puzzled by this, I thought I was shorted 2 bolts. So I used loctite and re-used the old bolts. This was both good and bad as you will see later. I finished pad replacement Monday evening and did not take van for test drive, yet another dumb-assed mistake. Next morning I had an important errand and as I drove out I noticed a rubbing/clicking noise from front right wheel. Bloody hell, drove back and popped that wheel to look. Rushed examination, pulled pads, noticed scoring on inside pad where it was hitting the un-worn area of rotor. Aha I thought, and beveled that part of pad a tad with stationary belt sander. Noise still there. Borrowed car and rushed out. I had the chance to drop by Autospiel that day and talk to Russ about this noise. I explained situation, he asked if I had checked that the rim, or balancing weights were not hitting caliper, I said no, I believed it was the pad on the un-worn part of rotor. Why don’t I listen and think? I decided to by a couple of new Brembo rotors from him (39 bucks a piece), and at same time, noticed them on the counter, a set of radius arm bushings (mine are old and worn out, I’ll post about replacement later, nothing to do with brake job). Got back home and set about rotor replacement.

This time, doing it right. First remove the pads. Undo lower bolt of caliper slider, in this pic I have 13 mm wrench on bolt and crescent wrench on flat of slider rod.

With that bolt out, the caliper body swings up and the pads exposed. Pull out pads.

Now those aneurism inducing 22 mm bolts (2) that hold caliper body to suspension upright. They are on tight (200 ft-lbs) and not much access for the lift deprived driveway “mechanic”. Shoot, forgot to state the usual warnings, ie support van SECURELY on jack stand/good wooden blocks during this procedure. You are really putting a lot of grunt into the van when loosening and tightening those bolts.

Ok, caliper off and hanging on breaker bar stuck in suspension. The slider part came off and is sitting to the right in this picture.

That hex socket bolt need to be removed, 5 or 6 mm? can’t recall.

Then the rotor should slide off the hub. Well, it started to but then hung up on something. At this point I really was not sure of anything, I consulted Bentley again, and again, finally used a puller.

I think it was this rust that was making the rotor difficult. Look at the state of it! What in the name of all that is holy was I thinking when I first decided to leave the rotors alone?

What it looks like with rotor off.

New and old.

New rotor on. I must say that it did give me a warm fuzzy feeling to look at it.

Caliper body re-installed and 22 mm bolts torqued back up to, ugghh, 200 ft-lbs. Pads installed, caliper slider swing back down into position and new bolt used in bottom position. You may find that you have to press in the brake piston to get the caliper to fit over new pads. I used a C-clamp to push piston in.

Other side done, wheels back on, tools put away, brow wiped. Ok, test drive…. rub, rub, rub. Son of a gun (or words to that effect), the noise is still there. Noise goes away when braking, that is a clue. On passenger side I had installed a no-name (drivers side is a Girling) caliper a couple of years ago when I broke the nipples off both calipers. I cannot recall why I got a Girling for one side and a no-name for the other side, but that is the way it is. I looked closely at the caliper. Oh yeah, scoring. So it seems that the added thickness of the new pads pushes the slider outboard enough to hit the rim (stock 14″ steelies yeah, yeah, I know I need bigger wheels. It is on my to do list)

And one of the curious little tits on the rim that is hitting.

Allright! Time to do some real work. Blending disc.

Grinding disc.

Caliper modified.

And yes, happy ending. Rubbing noise gone, and as a bonus, the brakes work.

Summary time:

– read the manual closely, don’t be a dolt like me and skim.

– replace rotors if replacing pads. Don’t screw around, the rotors are so inexpensive it is not worth having them turned. I suppose if you liked experimenting with different pads rotor replacement would get expensive. I have read that for good pad break in, the rotors (if not new or turned) should be scuffed to remove any old pad compound. But after all I went through, I’d recommend just buying new rotors and be done with it.

– be careful with those 22 mm bolts holding caliper on upright. The buggers are awkward to get full force on, don’t let wrench slip and for god’s sake support van well.

– think before and during  doing this job. Please don’t be like me.

– Russ told me that the Pagid pads I chose are excellent, the only downside is that they make more dust than the stock pads. That might be a concern if you had alloy wheels.

,

6 Comments