[Rick_1950]

Hello,
Thank you for taking the time to read this post.
I am having one heck of a time trying to get my 1999 93 Turbo started.
Not too long ago I replaced the head gasket after severely overheating the engine. I put a straight edge across the head in all directions and it seemed to be fine. A .005" shim would not pass under the straight edge at all.
I got it started but it was difficult, I did really have to crank on it over and over and over !! Once it started and ran for a while it was fine. It would not idle smoothly until it ran for a five minutes or so
I have been checking my valve timing. I have a SAAB WIS (Workshop Information System) CD and the instructions are with #1 and #4 cylinders at TDC (Top Dead Center) to align the notches on the cams to the marking on the block head near the sprockets. I have heard the the HAYNES MANUAL makes this same instruction and some users within this forum recommend not to go by this instruction.
Does anyone know why ?

I went the "OLD SCHOOL" way and brought #1 up to TDC by hand and made sure the marks were aligned. I put the cams back to where the car was once running and I still can not get it to fire up.
Before all this I did move the cam closest to the radiator because it looked to be off by just one tooth on the sprocket, when I started it, it sounded like marbles bouncing around inside the engine, I am thinking I damaged the valves ;oops:
When I try to start the car now it sound like there is no compression what-so-ever. It sounds like a little cranking sewing machine
I have been working on cars for many years but this is the first time I ever got involved directly with exhaust and intake valves, especially on SAAB's.
Could someone tell me how to check for bent or bad valves ?
Any information will be appreciated. Thank you for your time.
Rick

 

[earthworm]

I should be able to handle "bent valves", as a few years ago I worked on a hopeless Jaguar DOHC engine basket case..... a hell of a change from a two-stroke Saab..

For the uninitiated, the engine markings are just fair to poor, IMO; best to make your own highly readable alignment marks before disassembly...
Bent valve stems will hang up, resulting in horrific valve lash(.500 rather than .005) and of course no compression, in that, if not all cylinders..

 

[Diosnoche]

Unless you have a visual acuity better than 20/20, I don't see how you with your naked eye could tell if the heads were warped or not. Tolerances are in the microns when it comes to these interference engines, their isn't room for mistakes.

You probably should have just removed the heads and send them out to a machine shop

 

[PMI]

Leakdown Test, or, how many backyard mechanics does it take...

Could someone tell me how to check for bent or bad valves ?

Since you suspect no compression, I would just do a compression test first, and then a leakdown test one each cylinder (if you have access to a leakdown tester).

On the Saab engine, you can use a mechanic's stethoscope on the intake or exhaust manifold to hear which direction the air is escaping. That tells you if an intake or exhaust valve is not sealing.

To get a good feel for this, it takes two people (three, if I happen to be one of them!). One listens with the scope, the other one turns the crankshaft back and forth a fraction of a turn using a socket and extension on the crank pulley bolt. (A third person can take down the readings from the leakdown tester gauges.)

Start at TDC for a cylinder, and turn the crank in one direction until the intake valves open a crack. If all is well with a cylinder, you can hear the air rushing into the intake as the intake valves crack open. Then as you turn the crank back, and the valves seal, the sound in the intake stops. Continue to turn to the point the exhaust valves open, and you should be able to hear the air going into the exhaust manifold.

Repeat with next cylinder, etc.

(you did say OLD SCHOOL, :cheesy: )

 

[Turboken]

Cam timing

Hi,
I had the same problem after a headgasket change on my 9-3, i also used the marks on the cam blocks for alignment (as per the Haynes manual ) ,but i have found out that you should use the yellow painted links on the camchain as they are more accurate. Once i did this it solved the problem.

Check out my post on "Cam Timing".

Kenny.