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Discussion Starter #1
2-in-1 thread here.
The first problem is that the car is not holding fuel pressure after being switched off. I've got a fuel pressure guage so I can see this..
When starting, the fuel pump primes, but it doesn't hold pressure for more than a split second. Apparently it is possible to replace the internals of the check valve without removing it from the crappy plastic line. Anyone done this? I know that others have clamped rubber hose over the old plastic line, that doesn't sound great though.

Second issue is that I'm going to tackle the head gasket pronto. The current gasket was doomed from the offset to a short life, as I didn't realise that the bolts hadn't been torqued correctly at installation.

I plan on pulling this engine out in a few months, so I'm wondering about reusing the head bolts. I know you can apparently re-use them, but these are not genuine saab head bolts. They were replaced at the time of engine "rebuild", and were purchased from partsforsaabs. They are "aftermarket swedish" - ie scantech.

Apparently only the original saab headbolts could be re-used.
I've heard that saab changed the spec so that one bolt could be used for all engines, and so newer genuine bolts and aftermarket bolts are stret
ch to yield, can't be re-used. Anyone know for certain?
 

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philb said:
Second issue is that I'm going to tackle the head gasket pronto. The current gasket was doomed from the offset to a short life, as I didn't realise that the bolts hadn't been torqued correctly at installation.

I plan on pulling this engine out in a few months, so I'm wondering about reusing the head bolts. I know you can apparently re-use them, but these are not genuine saab head bolts. They were replaced at the time of engine "rebuild", and were purchased from partsforsaabs. They are "aftermarket swedish" - ie scantech.

Apparently only the original saab headbolts could be re-used.
I've heard that saab changed the spec so that one bolt could be used for all engines, and so newer genuine bolts and aftermarket bolts are stretch to yield, can't be re-used. Anyone know for certain?
Didn't we all do this in another thread last week...?
Ah, here y'go.
http://www.saabcentral.com/forums/showthread.php?t=113095

My take at the time - and I still hold it - is that a set of bolts is so cheap that it's daft to take the risk. I've been there, same as you - incorrectly torqued head taking out the gasket.
 

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Discussion Starter #3
The bolts cost more than the gasket. If they were the original saab bolts, yes, I'd re-use them. My question is regarding the aftermarket scantech bolts ( which are the only bolts sold by pfs ). Just wondering if anyone had any thoughts on those bolts, in particular.
 

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Discussion Starter #5
Not ordering the gasket kit, as I will not be removing the manifolds. Ordering the gasket from mysaab in Ireland. Shipping on the bolts would cost as much as the bolts, maybe more.
 

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TooMany2cvs said:
Didn't we all do this in another thread last week...?

My take at the time - and I still hold it - is that a set of bolts is so cheap that it's daft to take the risk. .
Does anyone know of a failure caused by used head bolts....ever? I was in the car business for decades and never heard of such a thing until I stumbled on this website.

This would have to be verifiable, not just some mechanic's excuse for having scrawed up the job.
 

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Jim Mesthene said:
Does anyone know of a failure caused by used head bolts....ever?
Impossible to prove whether the failure I mentioned in that other thread was caused by re-used stretch bolts or an incompetent numpty failing to torque properly - but they were definitely re-used and over-long.

I was in the car business for decades and never heard of such a thing until I stumbled on this website.

This would have to be verifiable, not just some mechanic's excuse for having scrawed up the job.
So the entire concept of stretch bolts being used once only, as recommended widely, is a con designed to part fools from their money? It wouldn't be the first, true, but...
 

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TooMany2cvs said:
So the entire concept of stretch bolts being used once only, as recommended widely, is a con designed to part fools from their money? It wouldn't be the first, true, but...
Jim is the second Saab tech I've heard advocate re-using head bolts unless they measure long vs. the others. Some car makers just spec really stout parts.
 

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Discussion Starter #9
Although that doesn't necessarily mean a thing for the headbolts that I'm pondering re-using, since Jim would have used genuine saab bolts. I am going to chance it anyway and re-use, will measure the bolts.
 

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TooMany2cvs said:
So the entire concept of stretch bolts being used once only, as recommended widely, is a con designed to part fools from their money?
Look here for a clear, concise explanation of how the bolts work (I thought we just did this?):

http://www.oliver-rods.com/library/libraryindex.html

They will explain how torque-to-angle (not torque-to-yield) bolts work. They have a pretty good story that matches my experience. The SAAB service manual does not suggest that head bolts are a one-time-use item. The SAAB factory schools I went to never suggested that head bolts were a replacemnt item (measuring the length was required).

I'm just some stranger on the internet with other oddball views, such as using high temperature thermostats, Fram oil filters (if they're cheap), 10k mile oil change intervals, any anti-freeze you want, etc. It's your car and your money. You get to choose whom to believe and what pitfalls to fear.
 

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Jim Mesthene said:
I'm just some stranger on the internet with other oddball views, such as using high temperature thermostats, Fram oil filters (if they're cheap), 10k mile oil change intervals, any anti-freeze you want, etc. It's your car and your money. You get to choose whom to believe and what pitfalls to fear.
I certainly don't intend to pooh-pooh your obviously considerable experience, Jim... I'm merely a reasonably competent DIYer lucky enough to have a good mate who's a very experienced (non-Saab) ex-dealer-mechanic-trainer and has run a workshop himself for many years.

As I said in the other thread - I know he _always_ replaces stretch head bolts once they're torqued - even if the engine's barely been run - and I assume that's not through the fun of it.

The differing attitudes and opinions of broadly similar people always intrigues me.
 

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Since I can get the Mann/Mahle filters for about as much as I can get the Frams, unless I need a filter right now I would just pass on the Frams. About the bolts, well, if I keep the Saab for as long as I would like to I will find some studs for it.
 
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