Timing Belt Failure broken pulley bolt
#20
Rennlist Member
Thread Starter
All pictures over head! :-(
As you can see the inner timing belt protection plate is broken and the ring behind the tooth wheel at the crank.
Also the pulley is very deformated from the broken belt.
The heads have much carbon building up in a few cylinders,maybe broken piston rings.
Oil consumption was a little bit on the high side the last few month.
The bores are o k, a few pistons have also much carbon on it.
The shop clean today the heads and flow the valve seats to show if valves are bend.
I think I change all piston rings,the full gasket set and rod bearings plus crank bearings.
So much work is done and I think we should do it right.
As you can see the inner timing belt protection plate is broken and the ring behind the tooth wheel at the crank.
Also the pulley is very deformated from the broken belt.
The heads have much carbon building up in a few cylinders,maybe broken piston rings.
Oil consumption was a little bit on the high side the last few month.
The bores are o k, a few pistons have also much carbon on it.
The shop clean today the heads and flow the valve seats to show if valves are bend.
I think I change all piston rings,the full gasket set and rod bearings plus crank bearings.
So much work is done and I think we should do it right.
#22
Team Owner
if you can get your hands on a newer tensioner and tensioner arm then you can put on a newer S4 style WP on unless your converting to a Porkensioner
#23
Rennlist Member
These are ugly pictures, upside down or not. How many kms on the plugs? Looks like a ring job was past due. Doesn't matter who deferred the maintenance, this (shoulder bolt syndrome) looks like a classic reason to change to Ken's tensioner.
#25
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#26
Race Car
I converted to a Porkensioner two years back when a leaking rebuilt WP forced me to tear into it. Didn't even have a second thought about it.
Dan
'91 928GT S/C 475hp/460lb.ft
Dan
'91 928GT S/C 475hp/460lb.ft
#27
Three Wheelin'
Join Date: Feb 2009
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Sorry to hear of the failure. I always wondered about that bolt, when I bought my car and did my first timing belt the PO replaced that shoulder bolt with a bolt and sleeve that I found bent. I switched to the Porkensioner with my last TB job, shoulder pivot bolt is not used, much better system IMHO.
Good luck with the rebuild.
Good luck with the rebuild.
I replaced my belts, Waterpump, and installed the Porkentensioner, my shoulder bolt was also slightly bent and caused the stock tensioner to wobble . Now my belt tracks straight as it should.
I would strongly recommend replacing the stock hardware with a Porkentensioner .
#28
Inventor
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I'm about to put a Racing belt on my '85 5-speed, although it's a bit after the horse(power) has left. I installed a PKT w/o removing the balancer when I bought it (almost exactly) two years ago. I kept the Porsche stamped belt with unknown number of miles already on it. Since then, while perfecting my S3 chips, I've done over a thousand WOT runs from 2000-6500+ rpm, hundreds of those to over 110 mph - many up to 140 mph, and a few well north of 7000 (by accident when I was testing the No-Lift Shift code), plus tens of dyno runs.
All this with no maintenance, and no worry. Basically, not even thinking about the timing belt.
All this with no maintenance, and no worry. Basically, not even thinking about the timing belt.
#29
Rennlist Member
Thread Starter
Thank you all for the good wishes and advices!
The waterpump is two years old and has ~ 40000 km.It´s the second Laso after the bearing of the first fail after 40000 km.
So every 40000 km a full tb service.
The plugs have ? 15000 km . They are the cold plugs Ken mentioned for his chips.
The waterpump is two years old and has ~ 40000 km.It´s the second Laso after the bearing of the first fail after 40000 km.
So every 40000 km a full tb service.
The plugs have ? 15000 km . They are the cold plugs Ken mentioned for his chips.