- Joined
- Mar 13, 2021
- Messages
- 19
I inherited a 1999 4.6 V8 F-150. It has 283,000 miles on the engine. It was smoking big time on start up. After starting it up and the massive smoke cloud blew out, the smoking almost went away, there may have been some slight smoke still while running but it was too close to tell for sure. So, my father and I took the valve covers off and changed the valve stem seals. Those original valve seals were utterly worn out. There is now very little smoke on start up, far less than before the valve steam seal change, but there is still some smoke on start up. The color of the smoke is kind of whiteish, same as before the stem seal change. However now after start up there is definitely no smoke at all when running.
My question is this - if there is still smoke on start up but zero smoke when running, does that mean the piston rings are burnt? The truck still has good power, I can light up the wheels from a dead stop, and the gas mileage is about right for a V8. IF the piston rings are burnt, will running full synthetic oil "restore" the rings or help them out and reduce the smoking even further? The guy who had it before foolishly only ever ran conventional. IF the rings are not burnt, what could still be causing the smoking given that I changed the valve stem seals already?
Thanks in advance.
EDIT - Actually, the truck now only smokes on start up if it sits for awhile, like if it sits a few days and I start it up, it blows off a little smoke still and then completely stops smoking. However if I run it and then crank it up again two hours later, there is no smoke on start up or at all. If the rings were burnt, wouldn't it constantly smoke?
My question is this - if there is still smoke on start up but zero smoke when running, does that mean the piston rings are burnt? The truck still has good power, I can light up the wheels from a dead stop, and the gas mileage is about right for a V8. IF the piston rings are burnt, will running full synthetic oil "restore" the rings or help them out and reduce the smoking even further? The guy who had it before foolishly only ever ran conventional. IF the rings are not burnt, what could still be causing the smoking given that I changed the valve stem seals already?
Thanks in advance.
EDIT - Actually, the truck now only smokes on start up if it sits for awhile, like if it sits a few days and I start it up, it blows off a little smoke still and then completely stops smoking. However if I run it and then crank it up again two hours later, there is no smoke on start up or at all. If the rings were burnt, wouldn't it constantly smoke?
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