View Poll Results: Your Belt Failed - What Specifically?
Water pump seized - Valves bent
4
23.53%
Water pump seized - No valves bent
4
23.53%
Belt snapped at one spot - Valves bent
0
0%
Belt snapped at one spot - No valves bent
0
0%
Belt eaten by crank gear or others and snapped - Valves Bent
0
0%
Belt eaten by crank gear or others and snapped - No valves Bent
0
0%
Belt stripped teeth - Valves Bent
2
11.76%
Belt stripped teeth - No valves Bent
0
0%
Roller arm snapped - Valves bent
0
0%
Roller arm snapped - No valves bent
0
0%
Roller arm bolt/stud bent - Valves bent
2
11.76%
Roller arm bolt/stud bent - No valves bent
3
17.65%
Roller bearing seized - Valves bent
0
0%
Roller bearing seized - No valves bent
0
0%
Oil pump seized - Valves bent
0
0%
Oil pump seized - No valves bent
0
0%
Cam timing gear chewed belt - Valves bent
0
0%
Cam timing gear chewed belt
0
0%
Crank timing gear chewed belt - Valves bent
0
0%
Crank timing gear chewed belt
0
0%
Guide Washers caused failure - Valves bent
0
0%
Guide Washers caused failure - No valves bent
0
0%
Tensioner collapsed / broke - Valves bent
0
0%
Tensioner collapsed / broke - No valves bent
2
11.76%
Belt was oiled - Valves bent
0
0%
Belt was oiled - No valves bent
0
0%
Voters: 17. You may not vote on this poll
Common TBelt Failure Modes - VOTE YOUR FAILURE
02-10-2006, 11:56 AM
#1
928 Collector
Rennlist Member
Rennlist Member
Thread Starter
Common TBelt Failure Modes - VOTE YOUR FAILURE
In reply to Cobalt's post about kevlar belts: I'm hoping we can post multiple choices, otherwise please choose the best fit.
02-10-2006, 12:50 PM
#3
Captain Obvious
Super User
Super User
Originally Posted by Rick Carter
None of the above; bushing in tensioner arm wore, no !, 8 bent exhaust valves.
Same for me too, tensioner bushing worn out AND tensioner roller bearing worn out. Belt jumped 3 teeth on the passenger side and 4 teeth on the driver side.....NO BENT VALVES!
When I bought the car, the water pump bearing failed and seized, the t-belt heated up and jumped a few teeth. Exhaust valves got bent on the passenger side.
My car is an ’85 32V 928.
02-10-2006, 01:27 PM
#5
maybe delete this one and start another..more generic at first..like ...stripped teeth, broken belt, or shredded belt..
and then get into more details as to why each of the above happened...
In my case the tensioner was not oiled..causing overtensioning leading to excessive wear on the cam gears which cut into the teeth on the belt..and one hot engine crank later..stripped those teeth right off at the crank gear....
Later,
Tom
89GT
and then get into more details as to why each of the above happened...
In my case the tensioner was not oiled..causing overtensioning leading to excessive wear on the cam gears which cut into the teeth on the belt..and one hot engine crank later..stripped those teeth right off at the crank gear....
Later,
Tom
89GT
02-10-2006, 02:29 PM
#6
Rennlist Member
.... another exception: water pump bearing cage failed, shaft tilted sideways knocking the plastic impeller into freewheel .. and the stalled pump pulley chewed ~1/8" off the belt as the belt lost tension due to the tilt in the shaft ... bringing in the "!" alarm as the coolant boiled over too ...
The belt never failed!!!!! Oh, and the pump seal did not fail!
BTW, I've just finished a pump replacement on Jeff's '89: Typical seal loss creating coolant leakage; however, the pump bearing was stiff ( as in packed with sand), and the back side of the TB was scuffed up . This one was well on the way to a seized bearing ... overheat of the belt .... coolant boil over ....alarms!!! .....TB failure - if not caught...
The belt never failed!!!!! Oh, and the pump seal did not fail!
BTW, I've just finished a pump replacement on Jeff's '89: Typical seal loss creating coolant leakage; however, the pump bearing was stiff ( as in packed with sand), and the back side of the TB was scuffed up . This one was well on the way to a seized bearing ... overheat of the belt .... coolant boil over ....alarms!!! .....TB failure - if not caught...
Last edited by Garth S; 02-10-2006 at 04:01 PM.
02-10-2006, 02:40 PM
#7
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Join Date: Mar 2003
Location: Nashua, NH
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Jeff needs to send a contribution to the 928 shrine! He's also lucky to have you there. I don't imagine there are many accomplished 928 mechanics between Truro and Halifax, or between St. John's and Montreal for that matter.
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02-10-2006, 04:01 PM
#10
Rennlist Member
Thanks Ernie 'Acomplished' may be an overstatement, but we'll both settle for 'available' 
.
Andrew - for the shrine, would you settle for an 'experienced' TB - one that's been around the block a few times ( puns are terribly sick!
sorry) .... there are several to choose from, all in basic black.
'Acomplished' may be an overstatement, but we'll both settle for 'available' .Andrew - for the shrine, would you settle for an 'experienced' TB - one that's been around the block a few times ( puns are terribly sick!
sorry) .... there are several to choose from, all in basic black.
02-10-2006, 06:44 PM
#12
Cottage Industry Sponsor
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When I bought my car, the timing belt light was on constantly. They retensioned the belt, and it seemed fine for a day. They proceeded to do other work, and went for a test drive. It then started making louder and louder squealing noises. They said that one of the rollers had a bearing missing completely.
02-11-2006, 12:11 PM
#13
Race Director
Nicole
You got lucky!!! Almost ended up like my car did with the PO....noisy leaky waterpump....ignored....blew up on the San Mateo bridge!!! Engine go bye bye....made for a cool post on here though...but I can't seem to find it? It was 6-6-2004 posted by constantine?
You got lucky!!! Almost ended up like my car did with the PO....noisy leaky waterpump....ignored....blew up on the San Mateo bridge!!! Engine go bye bye....made for a cool post on here though...but I can't seem to find it? It was 6-6-2004 posted by constantine?