Date: Sun, 2 Jul 2006 12:14:48 +0000 (UTC) From: Craig's Saab C900 Site <c900nospam.apana.org.au> Subject: Re: [Saab_c900] 8V turbo engine problem - might be head gasket
"hippo" <johnhnospamam.shoal.net.au> writes: >All your points are probably worth pursuing, but have you tried the >following stuff first? I'm sticking to my old principle of >cheapest/easiest first often saves time, money and knuckles... > >When I bought the 81 turbo it was running on 2.5 - 3 cyls for about half >an hour. Highway run sorted out a lot of that. Check the resistance on >your plug leads. They can look fine but be rubbish anyway. They're all new! I replaced them because the old ones were a bit burnt from heat off the turbo and downpipe. I also replaced the distributor cap, rotor and also the spark plugs themselves with new NGK BP7ES's. >The metallic thrashing in mine above 3600 - 4000 dpending on temp >logically / finally seemed like it might be timing chain related. It's >gone away since the injectors were changed. The fuel consumption has >improved at least 30% too! Have you run a flow test lately? Mine was more >like a drip test, poor old thing. Steve can still get the turbo injectors >in, or he could 3 months ago anyway! Well I can't get an accurate timing figure off the driveplate at the moment. When I tried yesterday the number on the driveplate wasn't readable with the revs as close to 2000 rpm as I could get them (going on the tacho reading on the timing gun). It might just be that the numbers on the driveplate are worn off though. I don't know what sounds to listen for in terms of timing chain problems, but when the engine was running every so often there is a dull thud which seems like something's igniting at the wrong time. It's sort of like the sound that a gas BBQ makes when the gas is first ignited and there's a tiny 'pop' sound from the small air-vapour explosion as the gas starts to burn. I can't work out when that's coming from but it's definitely internal somewhere. >Mine smokes (white) wonderfully if it's left idling for a while or >started/stopped several times and not run - especially when the nose is >pointing downhill. I suspect it's oil buildup either in the chambers or >the turbo because it goes away pretty soon (less than 5 minutes). >Mostly cheap and quick stuff to try anyway. See how you go and hopefully >it'll save you a big bill. Cheers Thanks very much for the advice. I am hoping it's not a cracked cylinder head but I've still got the one on the engine in the donor car to use, though it's probably corroding a bit as that engine has not turned in more than 3 years and most external bits are missing. I actually have two new K-jet injectors here also but I'm not sure if the same Bosch part number was used in the non-turbo and the turbo engines. Probably was the same though I'll try to check using some references sites I've got linked on the tech library page of my site. I will check the injectors for fuel flow since I don't think I have done that yet. Might be a good time to change the injector seals also. It still has oil smoke flowing up from the exhaust side of the engine when running too. It's a small plume of burnt oil that comes up from around the centre of that side of the block. I think the turbo oil return pipe goes into a port there somewhere and it might be that connection that's leaking. Regards, Craig. -- Craig's Saab C900 Page at | Craig's Classic Saab Workshop - Sydney .au http://nospam/~c900 | http://www.classicsaab.net and other URL's Email: c900nospam.apana.org.au | For Saab 99/C900/9000 Enthusiasts World-Wide! Alternate: saabonautnospaml.com | Web-forums, galleries, library, links, etc.
