SaabCentral Forums banner

1 - 10 of 10 Posts

·
Registered
Joined
·
751 Posts
Discussion Starter #1
i've just rebuilt my head and timing. replacing gaskets as i went.

upon starting the engine it ran really rough. im getting pinking on acceleration and not getting full boost...APC kicking in?!?

anyways i've just done a compression test :

cyl1 : 150psi
cyl2 : 150psi
cyl3 : 130psi
cyl4 : 160psi

i noticed im getting coolant out the exhaust this morning when i started her up.

do you think a retorque of the headbolts could help. should i check cam clearances?

a note - i didnt lap the valves when i put them back in. mainly because i was afraid of damaging them. i did however put them all back in where they came from. i was very precise with that.

also when i tried to align the cam shafts with the new sprockets and chain on i couldnt get the markings to line up exactly. there pretty close but not perfect. twinsaabs site said he had the same and left it at that. i wonder if this is acceptable?!

any help appreciated!
 

·
Registered
Joined
·
7,088 Posts
a retorque might help, but unless you did a compression test before removal you will not know if you had varying compression, it might be a fraction of valve clearance but normally the slightest gap and compression would very low if any.
I once had a sunbeam rapier and the twin carbs were badly out of sink when i got it. they were balanced up and it ran miles better, but when doing a compression test later the two front comps were different to the other 2, which i came to the conclusion that to much or to little fuel in a cylinder(or 2) creates more wear, hence varing comp so if an injector(s) is doing the same???? varying comps will arise. so next time check before then you will know if there all as good /better than before strip down as if only the h/g was changed they should be virtually the same.
 

·
Registered
Joined
·
5,677 Posts
did you set the timing properly afterwards? not knocked it while doing stuff and not got it set right now?
 

·
Registered
Joined
·
751 Posts
Discussion Starter #4
im going to take the rocker cover off tonight. see whats what. but basically i give up. im at work again, my rest period has finsihed so i dont have time to fanny about with it!:confused: Going to take it up to the local saab expert. he knows his stuff so it'll probably only be in for a day or so.....hopefully lol
 

·
Registered
Joined
·
2,901 Posts
If you torqued the headbolts properly, I don't think you'll need to again. The low compression is quite likely to be due to leaking valves. That was certainly the case on my car.
 

·
Registered
Joined
·
751 Posts
Discussion Starter #6
did you have to take the head off and lap them in? or did they eventually lap themselves? i think this could be one of my problems. i'm thinking coolant is passing via the inlet manifold as i had bother getting a seal there.
 

·
Registered
Joined
·
2,901 Posts
I didn't do the job myself. But yes, I got the mechanic to put head upside down, fill combustion chambers with thin oil, and leave it for a while. This shows you if the valves are leaking. Then they were lapped in. I think 2 valves were found to be leaking.
 

·
Registered
Joined
·
751 Posts
Discussion Starter #8
bullet proof test. just means i have to take the head off :( or the mechanic will :p

eitherway i need it done fast. i'll buy the new HG before i go up.
 

·
Registered
Joined
·
2,901 Posts
By the way - 150 psi isn't bad. The only cylinder with a slight issue is cyl3. But if you were confident it wasn't a headgasket issue, you could drive the car fine. My car has compression between 140 and 150, and runs fine.
 

·
Registered
Joined
·
751 Posts
Discussion Starter #10
its a 20-30 min drive to the garage so it wont hurt too much, slightest hint of overheating i'll stop. yeh 150 is what i was hoping for. cyl3 is a bit odd, all will come clear thursday when the bill comes :roll:
 
1 - 10 of 10 Posts
Top