Syncro Front End Rebuild

[alaskadan]

Nows the time for longer studs on those hubs if planning on using some of the alloy wheels out there.

[T3TRIS]

[MarkWard]

[mitch5]

What brand did you end up going with for the lower balljoint, the lemforder and moog seem to be on backorder everywhere.

[T3TRIS]

[T3TRIS]

Alright, inner races are off. The careful grinding trick worked great!

Here are photos of what the hubs look like. The photo with the pad of steel wool shows the surfaces lightly scrubbed.

Close ups of the surfaces, as well as measurements. My calipers are pretty basic so I only get so much precision but so far, the driver side hub measures 42.0mm all around and the passenger side (the one that had the loose axle nut) measures 42.0mm toward the base of the shaft and 41.9mm toward the tip. I have no idea what that would mean right now...

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Guillaume, Jennifer & T3TRIS
87 2-knob Syncro
- 94 Subaru EJ22, 225/70-R16 CLK 16x7 ET37
- Transaxle rebuild, Mexico paint job, Front end rebuild, 320Ah LiFePO4 Battery

[MarkWard]

They could be cleaned up better. Don’t press them, but see how the new races fit the hub. If the race drops down over, probably not good. If not, they will likely be fine. Unlike a conventional bearing, these inner races are fixed.

If they don’t last, you can replace them then.
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[T3TRIS]

[MarkWard]

Emery cloth is handy to have in the tool box. Works good for something like that. I’m surprised steel wool didn’t do a better job. Obviously you don’t want to take material off, so don’t get carried away. You want it snug. Just don’t want material sluffing off when it goes together. Freezing the hub before pressing it in does help.
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[T3TRIS]

Time for a front end update. Just like everything on this van, it’s taking longer than anticipated and requiring more parts and tools than I imagined, but still learning a lot!
Since removing the inner races off of the wheel hubs, I’ve done a few things.
Dropped off all the parts to a powder coater.

Pressed some 65mm studs into the hubs and put some epoxy paint on the hubs.

Pressed in lower ball joints.

Pressed new wheel bearings in the uprights.

Pressed the hubs back in (presses are so much fun!). The hub that had the loose axle nut and some sign of wear (41.9mm diameter compared to 42mm)was noticeably easier to press in. I’ll have to keep an eye on that I guess...

I also put the LCA’s back on the van with new powerflex bushings and that was a real PITA!! Is it supposed to be so tight?
I reattached the radius rods (no hardware was tightened).

I also started reinstalling the UCA but haven’t finished. I pressed the sleeves into the UCA and trucked along putting all the pieces back together, with bush-snot, when I remembered I was supposed to figure out “the gap” for the UCA powerflex bushings.

That’s where I’m currently stuck. Unfortunately, the assembly is full of grease which makes things tough to handle. I’ve tried tightening the assembly but the powerflex bushing was mushrooming near the inner part, against the eccentric washer. I didn’t want to tighten any more in fear of damaging the bushing.
I’ve read and re-rear the Syncro specific instructions made by the awesome Chris from T3 but I just feel confused by the process. I’d love to hear if anyone has a way to paraphrase these instructions, I’ll get some photos next week to illustrate my issue.
Also, are front wheel bearings supposed to be tough to spin after being pressed in? Is it the seal putting pressure?
Thanks and happy new year!!!!
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Guillaume, Jennifer & T3TRIS
87 2-knob Syncro
- 94 Subaru EJ22, 225/70-R16 CLK 16x7 ET37
- Transaxle rebuild, Mexico paint job, Front end rebuild, 320Ah LiFePO4 Battery

[MsTaboo]

Looking good! I don't have any input on the powerflex UCA bushings (I used OEM type on mine) but yes, the new front bearings will not spin freely due to all the seals, but you should be able to spin smoothly-no binding!

The LCA assembly might have been tight because the receivers (not sure of proper word) were bent inward from over tightening by a PO. Mine slipped right in with a little wiggling. I used Burly bushings, maybe smaller?
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Currently:
'90 Syncro Westy 3 knob w/Zetec

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[T3TRIS]

[T3 Pilot]

This is my pre coffee analysis of your uCAB fitting....

Do you have a variety of camber washer thicknesses?.
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1988 Vanagon

The most important part in every vehicle is the nut behind the wheel......

[remraf]

I didn't read your posts all that well but did notice you powder coated the suspension components. Powder coating adds thickness to the part so if the person doing the coating didn't mask or use plugs for holes you can have fitment issues. Don't think that is what you're describing here but thought it was worth mentioning.

[T3 Pilot]

Ok,

Two coffees in and now I can focus on your joint fitting issue.

First step would be to remove the purple bushings and inner sleeves and clean off all of the silicone grease.

Then you should measure the lengths of the sleeves and bushings, and measure the eccentric camber washers that you have. You need a set of calipers and a good steel ruler to do this.

Once you have some measurements written down you can adjust the lengthwise fit of the purple bushing with a sharp knife. The inner steel bushing clearance can be adjusted with a combo of various thicknesses of eccentric camber washers, ( they come in a range of from 4 to 6 mm in 1/2 mm increments I seem to remember) you will need to fine tune the length of the inner bushing sleeve with a belt sander clamped upside down in a bench vise. Check for squareness while you are doing this.

This process should require several test fittings and removals on/off of the Van. These are custom bushings and they require a custom fitting.
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1988 Vanagon

The most important part in every vehicle is the nut behind the wheel......

[MarkWard]

Hmm? I thought the inner sleeves supplied were longer than possibly necessary and would be shortened as needed.

The factory manual has a description to describe setting the clearance. It’s critical with the syncro because the arms are cast. The stamped 2wd arms are flexible to a point.

When tightened, the pivot bolt needs to seat on the camber washers and sleeves without preloading the bushings like you describe.
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[T3TRIS]

Ok cool, thank you all for the input (including the added thickness from powder coating comment).
You’re both confirming what I was leaning towards but I needed to hear it from others! Unless I missed it, nowhere in the instructions does it mention cutting the bushing itself.
Hopefully I can get the gap right just with eccentric washers, we’ll see. Seems like the thinnest I can get those is 8mm (combined). I’ll measure mine tomorrow but I’m getting a they are 5mm thick.
The instructions are worded in a way that makes me feel like “sometimes” the inner sleeves need to be adjusted. From reading comments, I’m thinking that it’s something that might always need to happen. As you mentioned, I’ll have to clean all the bushings and take measurements. I first regretted getting it, but now I’m glad I bought the big tube of snot from T3!
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Guillaume, Jennifer & T3TRIS
87 2-knob Syncro
- 94 Subaru EJ22, 225/70-R16 CLK 16x7 ET37
- Transaxle rebuild, Mexico paint job, Front end rebuild, 320Ah LiFePO4 Battery

[T3 Pilot]

Hi MarkWard,

Good to have you weigh in here. You are right about the shortening of the inner sleeve. I think the problem is that the OP is having trouble visualizing the process with the multi part powerflex bushings. The trouble is that the purple rubber covers up the face of the inner sleeve right where he needs to be able to see it to measure that .5mm clearance. He should start by having the thinnest eccentric camber washers installed that way he has less material to remove from the bushing inner sleeve.

I did mine several years ago and ended up making spacers from plastic plumbing pipe to replicate the thickness of the purple rubber flange where it is sandwiched between the inner and outer bushings on the outboard ends of the control arm wishbone. That allows you to see the inner end of the inner sleeve while test fitting. I took the whole thing on/off 6 or 8 times before I was happy with the fit. To be more clear, I removed the purple rubber bushing and replaced it with the shop made plastic spacer while dialing in the fitment of the inner sleeve.

There should be a slight axial compression of the purple rubber when the control arm bolt is tightened, too much squish is undesirable, so that is why I say you may need to trim some of the purple off.

Also keep in mind that the correct clearance of the inner sleeve is a maximum of .5mm at each side Before Tightening, so zero clearance would be OK. (Ref. Bentley 14.18a)
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1988 Vanagon

The most important part in every vehicle is the nut behind the wheel......

[MarkWard]

On my phone, so I don’t have the detail.

To clarify, the outer “hat” on both bushings must completely seat on the a arm. Yours are not seated. That is the first step to solving. If they aren’t flush, they won’t hold the A arm from floating backwards and forward. So, you must solve the fit with the bushings seated.
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[T3TRIS]

Thank you both, this is making A LOT more sense thanks to the back and forth.
You’re right about the bushings not sitting of course. I noticed right away but figured it just needed to be tightened since it doesn’t mention trimming it... but I stopped as soon as it looked like it was mushrooming severely!
Alright, the geometries and tolerances make sense, no problem with all that especially with both of your input. I think what threw me off was to not have any comment about trimming the bushing itself (sorry if I missed that).
Here’s what I’m thinking: it there’s zero gap, that’s less than 0.5mm and it’s ok. I can measure the space between the inner sleeves on the UCA when not installed and the space between the surfaces of the eccentric washers. As long as it’s less than 0.5mm on each side, I’m good. Then I can trim the bushing so that it’s maybe just 1mm longer than the inner sleeve. This way it will compress by 0.5mm up to 1mm when tightening.
_________________
Guillaume, Jennifer & T3TRIS
87 2-knob Syncro
- 94 Subaru EJ22, 225/70-R16 CLK 16x7 ET37
- Transaxle rebuild, Mexico paint job, Front end rebuild, 320Ah LiFePO4 Battery