vtraudt

Decided to keep the car and get in good condition (since the engine was deemed (forums, experts) NOT coming from the internals.

Timing belt job (no documented history when last changed) was high on the list (132k miles). Ordered and received.

Last 2 days done (water pump looked brand new, pulley, tensioner, belt also; looked like timing belt job was recently done).

But noise and 'floppy' (see posts here, incl. video/sound)made it in easy choice.

After the basic install, I sent an email to Blaupart, complaining (or suggesting something better) about the vague tensioning instructions ('90 degree twist'): "Don't like the timing belt tension instruction "can twist 90 degree". I found that settings from totally loose to steel wire tension allowed me to do the "90 degree". Pretty vague IMO. Wish I had a better suggestion, but short of a 'force vs. deflection' approach, I don't have a practical approach: (requiring a force meter) using one of those hook scales (fishermen and hunter use) and pull up the belt and get a reading for the force required for say 1/2 inch movement. "

Finished job today. Had turned engine 'cold' 4 revolutions. All fine. Cranked without spark a few times. All fine. Started first time, right there. Some whining noise; assumed new water pump to wear in and coolant to completely fill. Video/Sound during warmup:

http://s853.photobucket.com/albums/a...t=MVI_5801.mp4

Shut down after 10 min (warm). Refill coolant. Start, idle to warm up.

http://s853.photobucket.com/albums/a...t=MVI_5801.mp4

Wining remains (but not the before-timing-belt-engine knocking noise).

5 min into second run (idle), engine locks up:




Great!!! Timing belt broke. Must be my keyboard trained finger muscles are no good match for the 'tighten until you can barely twist belt 90 degrees'!!!!!!!

I can only hope that it occurred when idling, the valves are not bent, pistons not damaged.

What are my chances?

Luxus Panzer

So you think it broke because it was too tight or too loose?

vtraudt

Took everything off again.

Crank turns smoothly. Both cams turn. Did I get lucky, and the broken belt just shut the idling engine down because the valves did not open/close?

Should I put the old belt on, do the proper timing and do a compression test?

If valves are bent:
- have a complete head job done (vs. finding used set of heads with questionable history)?
- look for used engine?

Anything else that I should do to determine the damage and possible options I have?

vtraudt

Too tight. No question that's why it broke. Could have read the signs (squealing noise thought to come from new waterpump).
Just hate those totally subjective instructions. Seems I am the only one.
But judging by the looseness of the old belt (which is actually in very good condition, no wear on teeth, not cracks or wear signs), the previous guy apparently went the exact opposite of me: way too loose.
And from the 2x 10 min of run time from cold, the engine noise I was concerned about seemed to be gone; potentially caused by the loose belt.
Before the belt broke, I already suggested in the email to Blaupart to include an objective 'force meter' in their tool kit to more accurately allow proper tensioning of the belt.
I asked them to send a replacement belt asap and extend the loan time for the tool set; lets see how they respond.

vtraudt

I have good instructions for the timing belt change, but it is based on the engine being already timed right.

Can anybody quickly sent or link me to a good, detailed instruction to do the timing from ground up (with the belt broken while running, all 3 (crank and 2 cam) are obviously out of line.

Thanks.

CRAZY_RUSSIAN

http://12v.org/maintenance/repairs/tbelt.php
or
http://12v.org/maintenance/repairs/headgasket.php

vtraudt

id the timing.
Compression test (slow cranking battery, weaker first to last cyl; compression tester NOT screwed in very tight, since darn O'Reilly hose slips on connector and can't get adapter in plug hole out easily):

Cyl 1-3 (pass side front to back):

90, 90, 100

Cyly 6-4-5 (driver side front to back):
80, 80, 90

Previously: front 2 on both sides: 120, rear on both sides: 150 (with faster crank and tight gauge/adapter).

Since all 6 reading are in the 90 range (low, but considering the circumstances), does it mean valves are closing, are not bent?
What would I expect to see if valve is bent. Really low (like 10 or 20)?

Time to try test starting the car?

vtraudt

Engine test fired and run (briefly only, since no coolant etc. hooked up).

Rechecked tension (2 finger 90 twist) and set a bit lower (got burnt ones) and timing.

Once concern:

The holes on the oval index are NOT perfectly horizontal (within the play of the cam lock tool).

See the deviation from horizontal below, also difference between non horizontal (right on TDC mark) and horizontal (1/8 inch off mark).

Is it off by one tooth? Should I try to get both perfectly horizontal (without possibly sloppy cam lock tool)?

With the passenger side horizontal and crank on TDC mark:


Driver size NOT perfectly horizontal, TDC:


Position of driver cam not horizontal, TDC:


Position of driver cam horizontal, but NOT TDC mark:


Amount of diviation from TDC:

vtraudt

A few 3 second test runs worked well.
Lowered the belt tension further (I can now twist the longer run from water pump to passenger side cam easily, the shorter driver side run with 2 fingers (but still tighter than the old one was before the timing belt job).

Assembled all, filled with coolant. 5 min warm up run worked well.
Still hearing some whine (maybe paranoid now).

In the same (paranoid) context: Is it possible to install the thermostat the wrong way (I have now leaks). I have stuck the thermostat in wrong before (but noticed it before assembly). Not sure anymore if I paid attention this time.

What would happen with the thermostat installed wrong?
What symptoms?
How can I check with everything assembled?

I know......(stupid, stupid, stupid)

vtraudt

All back together, ran short warm up (less than 5 min). Eninge sound good.

Due to the slight offset (1/2 belt tooth) on the driver side, I decided to take the valve covers off and check the EXACT cam timing. There is supposed to be a timing mark.

Does anyone have a photo or sketch showing the marks and how ot use them?

I will post current situation. What are the 'allowable' tolerances?

If not good enough, I plan to wait for the new belt (in the mail), install and then do a "manual" timing (crank in exact TDC, cam bolts loosened, position each cam to exact timing mark).

Then:
- reliable (mine was not) compression test (dry), compare with numbers taken before timing belt job
- wet compression test (to find out if possible low compression is cyl/piston/ring related or valve/gasket)
- leak down test (further narrow down possible causes for low compression)