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307-occasional (oil) smoke from tailpipe

5K views 6 replies 6 participants last post by  Johnny Bravo 
#1 ·
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.
 
#2 · (Edited)
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.
 
#3 ·
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!
 
#7 ·
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.
 
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