Options for a broken timing belt. Fix, sell, junk?
#17
Drifting
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Off topic again....I thought we were on the subject of fixing a 951. Fix the car. It'll never ask you why you came home at 2 in the morning or where you've been. She'll never whine because you bought her timing belts instead of ear rings. "The more I know about women, the more I love my Porsche".
#19
Rennlist Member
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In two separate occasions with two separate 951's, I've had a timing belt break, and then come to find out it broke exactly at (or near) TDC and only required a new timing belt to get back up and running perfectly again, with no loss of compression.
So, it's worth putting a new timing belt on and checking compression before pulling off the head.
Just sayin'
So, it's worth putting a new timing belt on and checking compression before pulling off the head.
Just sayin'
#20
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I'm in redondo beach, calif. I don't have all the tools. I could only do the belt with exact step by step directions. Anyway to find out if it broke tdc? We've cranked it a few times since. Will that throw off all the timing? Probably huh. Thanks
#22
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In two separate occasions with two separate 951's, I've had a timing belt break, and then come to find out it broke exactly at (or near) TDC and only required a new timing belt to get back up and running perfectly again, with no loss of compression.
So, it's worth putting a new timing belt on and checking compression before pulling off the head.
Just sayin'
So, it's worth putting a new timing belt on and checking compression before pulling off the head.
Just sayin'
Motor was fine. A new belt and it runs like a dream again.
The simplest thing to do is get a "leak down" tester. Kinda like a compression tester but you can add your own air source.( which means you dont have to install a belt and crank the motor to test it ) You can buy a leak down tester from Harbor Freight for about $15, many auto parts stores will "rent" you one for free too! You will also need an air compressor or some other pressurized air source, HF sells those cheap too. (and they take returns
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Hook the leak down tester up to one cylinder at a time (screws into spark plug hole) then rotate the cam with a big wrench. ( big nut under the distributor cap and housing cover) You will be able to see (on the pressure gauge of the tester) and hear the valves open and close. Do this for each cyl. If you get one (or more) that won't build pressure then you have bent valves and need to repair.
This test allows you to diagnose it without having to buy and install a belt first. It should take no more than about 30 min and $50 in returnable tools(if rented of course, so no money out of your pocket)
Good luck!
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#23
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That sounds so simple I'm actually considering it. I already have the compressor. Once I crank the cam shaft, for the valve test, when I put a new belt on, how do I get everything lined back up again for timing? Also do I need special tools to loosen the tensioners to get the belt on? How do I adjust the tensioners and how tight? I've never gotten this deep into an engine, usually just surface items. How many items do I need to take off to get to the belt? Thanks
#24
Rennlist Member
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Look at Clarks garage. They have a great write up.
Basically you need to take the upper plastic cover off and then take the upper metal cover off (the one with the distributor cap on it) and you can see the cam belt tensioner and timing belt itself.
Basically you need to take the upper plastic cover off and then take the upper metal cover off (the one with the distributor cap on it) and you can see the cam belt tensioner and timing belt itself.
#25
Nordschleife Master
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That sounds so simple I'm actually considering it. I already have the compressor. Once I crank the cam shaft, for the valve test, when I put a new belt on, how do I get everything lined back up again for timing? Also do I need special tools to loosen the tensioners to get the belt on? How do I adjust the tensioners and how tight? I've never gotten this deep into an engine, usually just surface items. How many items do I need to take off to get to the belt? Thanks
#27
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It's not so much a "how much" or "how long" as it is "will it hold pressure".
Put as much or as little as you need to just see that it holds pressure on the gauge. A few seconds is enough, but it should hold for awhile. Just consider that it is a metal on metal seal so don't expect it to hold pressure like a basketball.
Put as much or as little as you need to just see that it holds pressure on the gauge. A few seconds is enough, but it should hold for awhile. Just consider that it is a metal on metal seal so don't expect it to hold pressure like a basketball.