Soon after the holidays, I plan to begin repairs on my oil leaks and consumption. I am the 3rd owner of this car and the odometer reads 58K miles. The engine burns oil excessively when started and continues until the engine reaches temperature, then is less visible out the tail pipes. I also have to place a drip tray under the engine and transmission when parked to protect my garage floor.


I know I have to pull the engine to seal up the leaks. I need your opinions on whether I need to remove the heads to address the oil consumption.


I have experience with A bodies, specializing in chevelles but this is my first oldsmobile.

 

I would give it a compression and leak down test before you pull the motor. That will tell you a lot more about the inside of the motor.

 

The oil leakage issue is easily addressed. The consumption issue not so much. I would also do a leak down and compression test prior to pulling it to see where your consumption issue is occuring. I would say the valve guide seals need to be replaced as a given, you'll find evidence of them scattered under the valve covers. I would also do a timing gear set and probably a water pump since your there already. Pull the pan and clean out the oil pump pick up screen.

 

Oil burning and smoke at start-up are classic bad valve seal symptoms. Do the leak down test as recommended by 442 Harv and oldcutlass. If the results are good, replace the valve seals with the heads still on the block.

X2 also on replacing the timing chain and gears while it is out and apart and checking the oil pump pick-up closely for debris from old valve seals and cam gear nylon.

Good luck!!!

 

Dont forget to change the rear main seal (rope seal). Replace it with the neoprene seal.

 

Is the neoprene seal a standard over the counter item? I may get a gasket set for a rebuild to make sure I have all the gaskets. Is there a gasket set part number I should be looking for?

 

SEAL, rubber rear main RRMS, SB Olds, Fel-Pro, Ford 292.
NAPA NGAJV748, FelPro BS-6141 292 ford, Victor JV-748

"Use the AMC 258 6 cylinder rear seal. It fits better [cut the tangs off the upper seal]" - Dan Macal, ROP.com, others too.

You will of course want to replace all the block and head freeze plugs while it's easy.

Do not disturb the plug at the rear end of the LH oil passage.

 

Thought I would provide an update. I completed a compression test. All but 1 cyl was between 170 and 185. #7 came in at 110. I pulled the heads. All Pistons look good. Thinking the valves and seals need attention. A bit of oil build up on the heads.
Timing chain has 3/4 " slop.
I plan to have the #6 heads freshened up, timing chain replacement. Rear main and pan seems to be not leaking. Transmission 200R4 leaks everywhere. I have the original TH350, but since gears were replaced with 3.42's I like the idea of an overdrive.
Once engine is assembled, I will pull the transmission and replace all the seals.
Please offer opinions.

Thanks.

 

The valve guides and seals are the most likely cause of oil consumption, so have the heads done.

FYI, your 79 IS an A-body. GM didn't change to the G-body nomenclature on the RWD cars until the 1982 model year, when the then-new FWD A-body cars (Cutlass Ciera, Pontiac 6000, etc) were released.

 

Ill add to pay particular attn. to cylinder #7 as that compression reading is a red flag.

 

Progressing with the repairs. Heads were cleaned, magged, and valves ground. Guides were good. New guide seals. Adjusted springs. Planning to keep the original cam and lifters (68K miles). Rear main seal replaced with JV748. Today's surprise was the replacement timing set, comp cams #2113 from Jegs, Chain was too long. Ordered another brand. Now have to wait another 3 days. Old nylon remnants of the original timing chain have been cleaned out.