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Discussion Starter #21
Ok I will take a look tomorrow. Can i ask one more thing - when in normal driving the overrun of the engine in between gear changes is very harsh and sounds like a rattling timing chain but is that the sound of the ticking lifters ? The timing chain is new and you can’t anything from there when I rev the engine with my head in the engine bay but inside the car when driving it sounds awful - it’s not the gearbox and gear changes are good this is engine sound but I guess it is the high speed spins of the knocking lifters ? I even a vibration through the pedals through gear changes. Before the head gasket change there was nothing like this going on and I’m pretty peed off that I spend 800 dollars to have the car back worse than I left it
 

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Overall what you're describing sounds like a timing chain problem - guides or the pad on the valve cover or cam sprocket engagement or something. I suspect the noise you're hearing generally isn't lifters but the chain rattling, and it it worse on overrun when there isn't engine speed tensioning it. Maybe a damaged or shot tensioner?
 

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Discussion Starter #23
I’ve just had a new chain and tensioner put in?? Before I had the head gasket and timing chain done I had none of these sounds or issues - the car was running great just had some oil leaking from the head
 

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Yes, so it's possible the new chain was incorrectly installed, the head was incorrectly installed, or the guides or the pad or the tensioner was damaged along the way.
 

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Discussion Starter #25
Hi again - still awaiting to get the car back to the mechanic - although on the phone he’s convinced the timing isn’t that noise I can here from inside the car between gear changes. But I’m starting to worry now - you guys saw the vids with the knocking sound ? Could it be a failed con rod bearing knock ?
 

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Sounds top-end to me, and the top end is where the recent work was. It could be something else - an exhaust leak at the manifold or something not secured and rattling around. But it sure sounds like valve train or timing chain.

Bottom end failures on B2x2 motors are basically unheard of.
 

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Discussion Starter #27
Reassuring - will find out this week when it goes back to the mechanic - presently have 16 new valve lifters soaking in oil ....
 

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Discussion Starter #28
Ok update to this issue and help needed !! So I need some advice! The 900 with top end knocking situation goes on. So you know the story so far - it was running fine but had a head gasket leak and left it with this so called specialist Saab guy in December to do the head gasket and timing chain, got it back mid January with that knocking noise that he said was the valve lifters and so I spent 2000kr on new lifters and he said he would solve it. He's had it again for three weeks and said he's replaced the lifters and the knocking noise is still there and now he thinks it's actually the pistons knocking and he said it's because it's a 2.1 engine and as he cleaned everything out it needs to settle in again and I should just drive it and it should go away ? Does that sound right ? Have you heard of this before that the 2.1 engine pistons need to settle in again after a head gasket change? He said it's totally fine to drive ? Would you drive a Saab with a loud engine knock ?
 

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No, that is 100% insane.

There is nothing you could do to the head that would have any effect on the bottom end.... they are totally separate systems. The only exception to that is if you installed the cams wrong you could create a situation where the valves in the head contact the pistons in the bottom end, but that would be the last moment of an otherwise very unhappy engine. Probably not the case here.

I don't know why this guy keeps coming back to "it's ok it will go away" but that's not a thing. You may need a little road time to get lifters working again or bed in brakes, but it's something solved in 15 or 20 minutes. There is no situation to give a car back without that small investment... I'm not even a mechanic and I wouldn't give a car back to a friend that wasn't 100% ready for the street... there is no reason to.
 

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Discussion Starter #30
He did give me two options which is weird "drive it and it may get better" or "leave it and I'll investigate further" - although I'm really worried about him tearing my top end apart again , he is going to solve it for free probably or at least half the cost of anyone else - the crazy thing all the other Saab guys who use him said he's the best .......
 

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The standout thing for me is that we went from "head gasket" to "crazy noise that is the lifters" to "it's the bottom end and it'll get better." I'm not sure I could tell one from the other but I feel like top end vs bottom end are distinct problems with distinct symptoms. And I still am having a really hard time with fine then work then sound. The work is CLEARLY the culprit... not some other unrelated issue... not statistically anyway.
 

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Discussion Starter #32
There is a little bit of lost in translation going on between me and him as he is Swedish - but he seems to think that because he cleaned out the top of the pistons and the side walls when the head was off that that has made everything too clean and it needs to build up with carbon / oil / deposits again ?? I don't know - I'll see what he says tomorrow ! I'm so confused !
 

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Kind of, sort of, but you'd really have to be doing things in a nonsensical way. It would be more likely for that to happen during assembly, but again, you'd be doing it wrong.

I don't buy into his explanation about cleaning ANYTHING creating a noise.

Do you have or can you get a mechanic's stethoscope? Knowing where the sound is actually coming from would be helpful.
 

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Discussion Starter #35
Ok so today the mechanic said he had this issue once before where he cleaned the pistons and then they made noise ? He suggested changing all the piston heads, bearings and rings - he assured me this would solve the problem.
One question - as I've just had the head skimmed for the head gasket replacement is it possible for the guy who did the job to skim too much causing the clearances to screw up ? I just can't see how replacing the piston heads, rings and rod bearings is going to solve this knock
 

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Ok so today the mechanic said he had this issue once before where he cleaned the pistons and then they made noise ? He suggested changing all the piston heads, bearings and rings - he assured me this would solve the problem.
Horse-Puckey!
He did something that stopped oil flowing to all the lifters, or bent, or broke something. Nothing 'got loose because it was cleaned,' engines are not held together by 'dirt, crud', or carbon. Unlike cheap clothing, metal does not shrink when washed.

If he won't fix it, find someone who will and send him the bill.
We've all made expensive mistakes.He made one, now he has to eat it.
 

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Discussion Starter #37
He's not admitting any mistakes - he first told me it was the lifters and he replaced all those and has rebuilt the top end twice (free I might add) now he says he can fix it by replacing the piston heads, rings and rod bearings - I have to buy the parts but he'll do the work for free. That's my options and if I take the car away and fix somewhere else then that's up to me - it will cost me triple and he will not cover it
 

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Discussion Starter #38
I really don't know what to do he's an independent mechanic and he did the work for cash so I'm kind of screwed - no comeback. I trusted this option because he was recommended by a guy I know and trust who had used him for twenty years for Saab engine rebuilds and never had an issue - so it's like I'm in some parallel universe where he suddenly knows nothing about Saab's ! The guy who recommended him is scratching his head saying he's the best guy in Sweden and he trailers cars 4 hours to him because he's reliable aMe so much cheaper than anywhere else in Sweden for Saab repairs. I kind of don't want to go to heads with him and lose the contact. He did 4 other jobs in the past with no issue and I was very pleased with the work and cost. This situation is a real pickle - anyone else I would start thinking of getting angry with but then I'm just stuck with a car that's probably going to cost around 2500 dollars in labour here compared to him doing it for free and just spend 600 dollars on parts.
 

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Discussion Starter #40
I also read this :


One of several errors in the Haynes workshop manual for the Saab 900 is the advice to bolt down the cylinder head with the pistons still at TDC (Top Dead Centre). Had this been done, the engine would have been destroyed. The reason is as follows: when hydraulic tappets are stored in an oil bath during engine disassembly, they seem to expand and suck in more oil. When reinserted into the head, the camshafts must be rotated several turns to allow the tappets to settle to a normal running clearance - only then will the amount of valve lift not be excessive. It is ALWAYS to be recommended that cylinder heads be bolted down and camshafts rotated to settle in any hydraulic tappets while the pistons are well away from TDC (i.e. a good inch below the top of any bore).
I discovered the problem as follows: having made sure the pistons were well away from TDC as the head was bolted down (which I thought was obviously a good idea!), I brought the camshafts to exactly their TDC position and then tried to rotate the crankshaft back to TDC in order to align everything ready to install the timing chain. The crankshaft stopped just short of TDC and refused to budge - obviously a valve had contacted one of the pistons and was jamming the engine. The cure was to rotate the crankshaft back away from TDC (reverse direction of rotation), then rotate each camshaft several turns to settle in the hydraulic tappets (this presumably permitted any excess oil within the tappets to escape), whereupon the crankshaft could now be turned to TDC when the camshafts were once again set at their TDC positions.
Thus, the engine could now be reassembled safely. With the camshafts driven by the timing chain the engine was gently rotated several times to confirm that all valves were clearing the pistons at TDC of all cylinders. If care in this part of the engine rebuilding had not been exercised (or if the instructions in the workshop manual had been followed unthinkingly), the engine could have been destroyed.
 
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