[Diy_efi] Re: +AFs-Diy+AF8-efi+AF0- Reality check - no efi content - long winded
Sun Aug 20 00:25:26 UTC 2006
OH WOW+ACEAIQAh- Man do I feel bad for you. As someone who travells alot I know how a road breakdown can be. Read on for my opinion...
+AD4- Some questions for the gang:
+AD4- 1) Is the 1988 Buick 3.8L V6 an interference engine? What are the
+AD4- chances we bent a valve?
YES and 100+ACU- Some will argue this but if there is any carbon in the valve releifs, it has become interfering.
+AD4- 2) They did a compression check before doing the work and said all 6
+AD4- holes were 120 to 140. They had to pull the valve covers and loosened
+AD4- the rockers since the cam wasn't turning. I can't imagine how this is a
+AD4- valid test since the valves didn't open on the suck cycle. Is there any
+AD4- way this could have been a valid compression test?
It is not valid done in this manner. They told you a story if they claim these numbers.
+AD4- 3) I did a compression test this afternoon (cam's turning now :-) ),
+AD4- I've got 30 psi in hole +ACM-1, 90 in +ACM-3, and about 120 in the others.
+AD4- Squirted oil in +ACM-1 and retested... still 30. I pulled the valve cover
+AD4- to try to fix the oil leak and while it was off I removed the 2 rockers
+AD4- on +ACM-1 and retested... still 30 psi.
This engine-butcher did not know his butt from a hole in the ground.
+AD4- 4) They spent 3.5 to 4 hours trying to remove the oil pan to clean the
+AD4- debris out of it (billed me for 4.3 hours). Is this reasonable for a
+AD4- Buick Century wagon? Seems to me there should have been another way
+AD4- other than removing all the stuff they did.
My Century has a different engine, no idea what is involved with pan removal on a 3.8. With a 3.1 the pan is +ACI-wide open+ACI- under the car.
+AD4- 5) Is there any way to check cam timing without taking the timing cover
+AD4- (+ACY- water pump) off?
If so I don't know how. Could probably be done using the cam sensor magnet position viewed through the sensor hole. Would have to compare another gear and chain set to determine where this magnet is actually located. in relation to TDC.
+AD4- I did some other checks too - all injectors are firing, I have spark in
+AD4- all 6. I'm thinking either a valve is bent in +ACM-1 or the cam timing is
+AD4- off. Any thoughts would be appreciated, my apologies again for the off
+AD4- topic post.
No apology necessary. I'll tell you now, if that engine threw a chain the valves are most certainly bent. I have rebuilt 4 or 5 of these 3.8's from same vintage cars. It will slightly bend the valves when they impact the carbon deposits in the valve releifs.
The mechanic who worked on this car should have known better than to attempt this repair without removing the heads. This engine is famous for these failures and +ACI-everyone+ACI- who works on GM knows about it. Did this crackpot claim to be a GM mechanic?
I would not trust this engine until it had been torn down and inspected / rebuilt. Especially if they had the pan off, no telling how many pounds of silicone have squished into the sump to clog the oilpump...
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