So I made the switch to a high mileage oil on my 240k 626 with ST 10-40w and now it smokes on startup until the temp starts coming up? Should I be worried and is this just temporary for cleaning maybe? The same thing happened a few years ago when a friend suggested I try a quart of Lucas and it smoked every startup until I changed the oil.
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Burning off on startup after HM switch
- Thread starter Dyoel182
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You might need to clean up the inside of your engine. I've been testing Auto-Rx given to me by Lonnie. It appears that the only problem with this product is that you have to be patient. It takes longer than 20 minutes to work, more like 2k miles. Your mechanic won't use it because he is challanged when it comes to lubricants. Also he makes more money with solvents. Solvents are a two step process for him. He gets paid in 20 minutes. Then if it does damage he make even more money. He does not make money waiting for you to drive around. You can use Auto-Rx to tell you what shape your engine is in. If after using the product two or there times you still have problems then you know that a mechanical repair might be in order or your car is now ready to be traded in for something newer. If you keep the car you will have some information to guide your repair process.
What weight oil were you using prior to 10w-40?
It could be some cleaning of the valve stem seals (sometimes rings), since smoking on startup is mostly associated with those. Give it a couple of oil changes worth and see what happens. Some synthetic users get some smoking because the oil has cleaned up some of the gunk around the rings, and while it's partially clean, oil gets past the rings, but after an OCI or two, the rings get cleaned and the smoking stops.
It could be some cleaning of the valve stem seals (sometimes rings), since smoking on startup is mostly associated with those. Give it a couple of oil changes worth and see what happens. Some synthetic users get some smoking because the oil has cleaned up some of the gunk around the rings, and while it's partially clean, oil gets past the rings, but after an OCI or two, the rings get cleaned and the smoking stops.
10w-40 and 15w40 are still both 40 weights, and the Xw is only determined by a cold cranking test, so it won't necessarily mean it's lighter (the 100 C viscosity of each will determine which is truly lighter). Unless your engine is that picky that a lighter 40 weight is burning off then it may be a viscosity issue.
How long as the 10w-40 been in use?
How long as the 10w-40 been in use?
I'm thinking the hot 10W-40 is seeping past your worn/split valve stem seals after shut off while the oil is draining back to the pan; and then when you go to start it back up again on the next cycle, you've got some oil sitting on top the valve that gets sucked in on the intake stroke.
If 15w40 was preventing that, I'd go back to it.
If 15w40 was preventing that, I'd go back to it.
The engine has 240k but the valve stem seals only have about 30k on them so I hope they havent already started leaking.
Originally Posted By: ConfederateTyrant
How long as the 10w-40 been in use?
The HM 10w-40 has been in the car a week now. Still smokes every morning when I start it up and for about the first mile when the temp gauge starts to wake up.
Originally Posted By: ConfederateTyrant
How long as the 10w-40 been in use?
The HM 10w-40 has been in the car a week now. Still smokes every morning when I start it up and for about the first mile when the temp gauge starts to wake up.
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Triple_Se7en
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It may take 2-3 OCIs to clear up without an Auto-Rx. Stick with it - even in summer.
The 15w40 is thicker as it cools down, so less seeps down overnight. I bet a #30 would also stop the smoking, and give slightly better gas mileage. But if you're in the cold parts of Tx, it might be too cold for that.
What color is the smoke? Is it black or white with a low odor or is it kind of blueish and smelly?
aehaas
aehaas
Its white with a burned oil smell to it. The same white as the damp cold morning start up but it follows you down the road longer.
Originally Posted By: oilyriser
The 15w40 is thicker as it cools down, so less seeps down overnight. I bet a #30 would also stop the smoking, and give slightly better gas mileage. But if you're in the cold parts of Tx, it might be too cold for that.
You mean a straight 30 weight?
Originally Posted By: oilyriser
The 15w40 is thicker as it cools down, so less seeps down overnight. I bet a #30 would also stop the smoking, and give slightly better gas mileage. But if you're in the cold parts of Tx, it might be too cold for that.
You mean a straight 30 weight?
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Quote:
The 15w40 is thicker as it cools down
Not necessarily, but the particular 15w40 could be thicker across the range than the 10w-40. Xw only means it passed a cold cranking test, not the physical viscosity at the given temperature.
The 15w40 is thicker as it cools down
Not necessarily, but the particular 15w40 could be thicker across the range than the 10w-40. Xw only means it passed a cold cranking test, not the physical viscosity at the given temperature.
Triple_Se7en
$50 Site Donor 2024
If it was the oil-only leaking, the smoke would be blue.
How many miles are on the high mileage oil? That's a more accurate one than how much time has the high mileage oil been in the engine.
Also, did it instantly start smoking the next cold crank after the oil change?
Also, did it instantly start smoking the next cold crank after the oil change?
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