Hi all. Been trying to find out why my 69 L-68 is running poorly, ignition all good I think, although I wonder if my distributor is worn, I get a slight scraping noise from the distributor cap at times. Erattic idle, off idle stumble. But:
Thinking the previous owner may have put the center carb manifold gasket upside down exposing the PCV and maybe causing a vaccum leak I pulled the center, and other two carbs.
Carb gaskets were on correctly, but I look down the intake holes and in the front runners mostly and some in the rear runners I have a small puddle of oil. PCV / hose does not have excessive oil and PCV runner in center of intake is a little moist, but does not look like it is sucking raw oil. When running there is no sign of burning oil. I pulled the center 4 intake bolts but no sign of oil on the threads.
Now, I just bought the car from a previous owner, and the owner prior to him did the engine rebuild. Stock except for a Comp Cam 280 Magnum. Car has been lying in a garage for a few years with minimal use.
Since that cam has specs close to a stock L-71 I put in a CV 941 PCV as called for for a L-71. Idle manifold vacuum in the 12" to 13" range. Now, I do recall after speaking to the guy who rebuilt the engine that he had the heads milled somewhat. Block not decked as the matching # pad is untouched.
So, any thoughts where the oil is coming from? I'm thinking if the heads were milled maybe the intake to head ports are off slightly and allowing oil in the intake. I have not run the car much other than idling, so maybe the high manifold vacuum has worked at pulling in more oil than normal driving.
Thanks. Doug
Thinking the previous owner may have put the center carb manifold gasket upside down exposing the PCV and maybe causing a vaccum leak I pulled the center, and other two carbs.
Carb gaskets were on correctly, but I look down the intake holes and in the front runners mostly and some in the rear runners I have a small puddle of oil. PCV / hose does not have excessive oil and PCV runner in center of intake is a little moist, but does not look like it is sucking raw oil. When running there is no sign of burning oil. I pulled the center 4 intake bolts but no sign of oil on the threads.
Now, I just bought the car from a previous owner, and the owner prior to him did the engine rebuild. Stock except for a Comp Cam 280 Magnum. Car has been lying in a garage for a few years with minimal use.
Since that cam has specs close to a stock L-71 I put in a CV 941 PCV as called for for a L-71. Idle manifold vacuum in the 12" to 13" range. Now, I do recall after speaking to the guy who rebuilt the engine that he had the heads milled somewhat. Block not decked as the matching # pad is untouched.
So, any thoughts where the oil is coming from? I'm thinking if the heads were milled maybe the intake to head ports are off slightly and allowing oil in the intake. I have not run the car much other than idling, so maybe the high manifold vacuum has worked at pulling in more oil than normal driving.
Thanks. Doug
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