| Author |
Message |
Mark Crost (Mrfotos)
New member
Username: Mrfotos
Post Number: 3
Registered: 5-2003
| | Posted on Tuesday, September 02, 2003 - 9:48 am: | |
Thanks For your Quick responce, Ill buy a leakdown gauge and get busy, Ill let you know what the results are and we can go on from there.
Thanks again for your exellent suggestions.
Mark |
Lee Hamner (Tennlee)
Junior Member
Username: Tennlee
Post Number: 204
Registered: 2-2002
| | Posted on Tuesday, September 02, 2003 - 4:38 am: | |
With all the cylinders on one bank uniformly down at the same time, it sounds like a timing overlap issue. They may not have kept the exact spacing between the two cams on that bank when they put on the belt. One tooth off could do this. |
Paul Jeffery (Peajay)
Junior Member
Username: Peajay
Post Number: 126
Registered: 4-2002
| | Posted on Tuesday, September 02, 2003 - 4:21 am: | |
Hmmmmm..... since the belts were just changed that sounds suspicious to me. My 328 has the sheet metal pointers bolted to the cam covers on the right hand side, I think the 308 has them also. Although these are not as easy and accurate to get a good timing on, they should be able to give you a good idea if one of the banks has a timing error. I would check this first. |
Malcolm West (Ferrari_uk_tech)
Junior Member
Username: Ferrari_uk_tech
Post Number: 81
Registered: 7-2003
| | Posted on Tuesday, September 02, 2003 - 3:47 am: | |
My first thoughts were fuel injection, running too rich, but if you feel that the problem is with one bank only it's unlikely to be an injection problem - however if it's associated with both banks you will need to look into the fuel system, I can give you data if you need it.
As David says get leakdown figures and depending on results I would verify that the valve timing is correct
MW
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David Feinberg (Fastradio2)
Member
Username: Fastradio2
Post Number: 304
Registered: 4-2002
| | Posted on Monday, September 01, 2003 - 7:44 pm: | |
Mark,
Here's my way of thinking, based on many, many years of experience.
Verify the mechanical integrity of the engine first, before going any further.
Let's get some leakdown figures...then go from there.
Regards,
David |
Mark Crost (Mrfotos)
New member
Username: Mrfotos
Post Number: 2
Registered: 5-2003
| | Posted on Monday, September 01, 2003 - 7:21 pm: | |
Hello Folks, This is my first Question to pitch out to you Chatters, My 1980 308 GTSi 2V injected had the timing belt change just before I bought the car. I have not driven it yet, but the engine runs rough, and Im not sure if the Job was done correctly. But before I take everything apart to get to the timing belts.
I did some testing, the rough idling engine pulls a slowly variable 8~9 inches of Hg.
The front bank compression is a healthy
162-165-165-160
while the rear bank is a concerning.
120-110-120-125
A squirt of oil in the cylinders and retest, adds 30 Psi. to those numbers
While idling (roughly) with both banks going, black sooty smoke is constant in the exhaust. With the removal of the high tension wire to the cap of the front bank, now the rear bank (with the low compression) is running all by itself and the Idle smoothes out nicely and the exhaust is much, much clearer.
Reattach the wire and back to the rough idle/smoke. now remove the high tension wire from the rear bank, and the engine dies instantly.
After removing the spark plugs from the rear bank it is possible to run the front bank
(good compression) solo with a very rough idle.
The brand new spark plug wires produce a powerful spark going to the plug.
And the new spark plugs in the rear bank are now a little bit sooty, and the front ones heavily sooty.
It seems to me that the ignition timing is off on the front bank, but good on the rear bank, Is it possible to adjust the front bank ignition timing independent of the rear bank? Or is this all from a slightly off timing belt causing the camshaft with the distributor rotor to be hitting late/early at the plugs, while still giving strong compression (valve timing)
Any suggestions of anything to check or test out Before having to remove all the parts to get to the front bank belt for inspection, will be very greatly appreciated.
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