: 307-occasional (oil) smoke from tailpipe



Cadillac_Fan
09-08-06, 08:31 AM
Is this a telltale sign that the engine is on it's last leg? It emits a brief, yet noticeable plume of oil smoke from the exhaust when I step on the accelerator on the highway. I don't care that it's burning and leaking oil too much, I just hope I can get a little more life out of my '88 Brougham before I have to say goodbye to her. Should I refrain from driving this more than three continuous hours? Thanks in advance for any help and suggestions.

kdrolt
09-08-06, 01:37 PM
Is this a telltale sign that the engine is on it's last leg? It emits a brief, yet noticeable plume of oil smoke from the exhaust when I step on the accelerator on the highway. I don't care that it's burning and leaking oil too much, I just hope I can get a little more life out of my '88 Brougham before I have to say goodbye to her. Should I refrain from driving this more than three continuous hours? Thanks in advance for any help and suggestions.

I used to know how to tell the difference between oil smoke from leavy valve stem seals, vs leaky rings, from observing what happens during driving vs coasting. Anyone remember?

Another way is a compression test on each cylinder because it's a direct test of the ring seal.... assuming the valves + valve seats are OK. And valve stem seals can be replaced without going inside the engine.

Cadillac_Fan
09-08-06, 03:33 PM
I used to know how to tell the difference between oil smoke from leavy valve stem seals, vs leaky rings, from observing what happens during driving vs coasting. Anyone remember?

Another way is a compression test on each cylinder because it's a direct test of the ring seal. And valve stem seals can be replaced without going inside the engine.
That would be a blessing if I did not have to get a rebuild. Thanks for giving me some hope with my tired 307!

90Brougham350
09-12-06, 01:52 PM
The "Great Blue Cloud" you see when you first start the car is usually a pretty simple indicator of bad seals.

boatman
04-11-07, 05:12 PM
hey, at least the upper cylinders are well lubed!

Hammondsix
04-15-07, 11:53 PM
Let the car idle for 10 mins. Rev it and observe. If the engine emits a blue cloud and stops smoking afterward, youre probably looking at valve seals. if the smoke is continous and not just puffs, its probably rings. If you need to change valve seals i suggest you go to www.lincolnsonline.com, They are experts on that particular issue;)

Johnny Bravo
04-21-07, 12:56 AM
Good news and bad news.

The bad news: Visible blue smoke is a sure sign the engine is well past the point of simply replacing valve stems seals.
Furthermore, even if it was only the valve stem seals replacing them would be a temporary, bad-aid fix as the valve guides are no doubt worn as well.
Moreover, if the motor still has the original nylon geared timing set that is a time bomb and should be more of a concern than a little blue smoke.

The good news: The 307 Oldsmobile engine is hard to kill and can run for a long time even if it burns oil, albeit at reduced performance, fuel economy and emissions.

I'd run a heavy-duty 15w-40 deisel motor oil, topped off frequently.