engine seized

[ant7]

4MM difference would definitely cause the issue you have!
Find the correct clutch pressure plate, and fit that! In the meantime; does anyone know from going on the measurements jimmy has provided; what his clutch pressure plate may be off ? and why someone would have fitted this if its clearly wrong ?
Ant.

Originally Posted by jimmyjimmy

Well that s amazing.
I took for really being sure we measured the same way another picture.

[stownsen914]

It’s worth noting that the ring gear added ~4 mm to the stack in my case. Jimmy if you measured them together then 29.5 mm is correct.

[jimmyjimmy]

Ok, so pp is not the problem.

[safe]

Git rid of those useless spring washers... I don't think they do anything good in this application.
If I don't remember wrong, I think there should a very thin washer under the head. I had my clutch out ~2 months ago. A Schnorr washer maybe?
These bolts aren't prone to coming loose, if you are the anxious type use some light duty Loctite.

[ant7]

The ring gear has to be more than 4mm in width, are you sure you didn't include it in the total measurement ? its important to know whether your measurements coincide with those of the OP otherwise we are just going round in circles, if it turns out that your overall measurements are the same as the OP's then we are back to square one!
In the meantime as the last poster mentions if the pressure plate bolts are not meant to have such thick washers under them, then removing them may be just enough, obviously I would still put a little lock-tight on each bolt just as a precaution.
Ant.

Originally Posted by stownsen914

It’s worth noting that the ring gear added ~4 mm to the stack in my case. Jimmy if you measured them together then 29.5 mm is correct.

[917_Langheck]

Originally Posted by safe

Git rid of those useless spring washers... I don't think they do anything good in this application.
If I don't remember wrong, I think there should a very thin washer under the head. I had my clutch out ~2 months ago. A Schnorr washer maybe?
These bolts aren't prone to coming loose, if you are the anxious type use some light duty Loctite.

The PET lists 900 027 015 03 (B series) lock washers, and 900 067 090 02 M8 x 42 bolts for securing the pressure plate. Wave washers were used in the 930, which would be a better choice; however, that shouldn't be the source of the stack height issue.

[Rsnellie]

Ok I’ve got two thoughts.

First and what I see as most likely of my two opinions is that the ring gear isn’t seated all the way. I suspect the person who built it removed it and didn’t reinstall by heating it up and allowing it to rest all the way down on the pressure plate. My original pressure plates needed heat to remove the ring gear. The ring gear gets removed so that you can use it to lock the flywheel in place to tighten the flywheel bolts. They only require like 16-17lbs of torque so it won’t draw the ring gear flush. This would account for the ring gear rubbing the back of the gearbox. It’s hard to tell because the ring is recessed on the mating side so it will look like it’s fully seated when it is not. I fortunately caught this on my clutch job when reinstalling. We need an actual measurement just like you took to be sure, but at first glance it looks to me like the rivets are sitting to far down in the ring. Most photos I see including my own they are almost flush to the starter ring gear.

Second, seeing how this looks to maybe be an older pressure plate and flywheel… perhaps they were original to each other and balanced together. I know older tolerances often times weren’t as accurate on some parts. Is it possible the mounting locations for each bolt securing the pressure plate to the flywheel aren’t exactly the same.. so that if you clock it incorrectly it could be offset slightly and causing the interference only on half of a rotation? Can it be reclocked so that it turns true? Is that something worth checking? Just throwing out random thoughts for you and sorry if it’s a waist of time.

I’ve always been taught to put indexing marks when separating pieces like pressure plates and flywheel. I don’t see them here, but it could be a scribe line not obvious in the photos

[stownsen914]

Originally Posted by ant7

The ring gear has to be more than 4mm in width, are you sure you didn't include it in the total measurement ?

4 mm is the flange thickness on the ring gear (the part that adds to the “stack” thickness). The overall thickness of the toothed portion of the ring gear is at least a cm I think.

[ant7]

Originally Posted by stownsen914

4 mm is the flange thickness on the ring gear (the part that adds to the “stack” thickness). The overall thickness of the toothed portion of the ring gear is at least a cm I think.

[ant7]

I think a bit of a recap might be in order, lets remind us all on what the original issue was, and what has been suggested and checked so far; otherwise we are just going round in circles;

The original issue of the partial seizing was found to be the clutch case bolts touching the two small bumps in the bottom of the gearbox casing, I am not sure any of us was aware of the ring gear also scuffing the case at that point, so our main concerns were first; are the correct bolts and washers fitted to the clutch case, next, is it the correct clutch case, next is the flywheel fitted correctly, i.e.; was there an even space between the flywheel and engine case at various crank positions, next, has the engine case been machined [not likely] next is there a possibility that the crank has been fitted to the engine correctly [unknown at this point]
There has to be a reason why the crank, flywheel, and clutch case all seem to be too far back, or protruding to far into the gearbox casing when both the engine case and gearbox casing are bolted firmly together, it may only be a few millimetres, but its enough for the clutch case bolts to foul on the gearbox case bottom.
Hope this helps.
Ant.

[puppynuts]

But it turned over when he first got it 5 years ago?

[jimmyjimmy]

I turned it just to see if not seized,probably didn t turn far enough.
Thanks for the summary Ant.
I'm still not sure about the distance flywheel-engine I'll take a picture and oen a new thread, perhaps people don't read this one anymore.

[ant7]

No worries Jimmy
Just frustrated we haven't been able to help you get to the bottom of it yet.
Ant.

Originally Posted by jimmyjimmy

I turned it just to see if not seized,probably didn t turn far enough.
Thanks for the summary Ant.
I'm still not sure about the distance flywheel-engine I'll take a picture and oen a new thread, perhaps people don't read this one anymore.

[jimmyjimmy]

No problem Ant, It's great so many people want to help here,even if it's becoming lengthy.
I want to thank everyone very much.

[john walker's workshop]

Years ago I had a 2.7 in the shop that popped out the flywheel seal. WTF? Turns out the crank was moving in and out because the #1 thrust main bearing was loose in the severely worn main bearing journal. New case time for that one.

[ed mayo]

Could the thick washer under the flywheel bolts have been installed between crank and flywheel instead of the correct side?

[911 SLANT]

Whats your measurement from case to ring gear. My measurements 42.16 to flat edge of case.

[jimmyjimmy]

I measure 40.8 mm from ring to protruding ring on case.

[jimmyjimmy]

Today i took all my courage and decided to remove that flywheel.
The special tool, breaker bar ,a jack to keep the tool horizontal.
15 minutes later flywheel was out without any problems.
This is what I found behind it,it surely is a new seal ...but is the crankcase coming out too much? I measured about 7 mm.

[jimmyjimmy]