Hello,
I just had my head gasket replaced by a mechanic, but there is still white smoke coming out. My mechanic said that the rings are done? Idk what that means. My friend who is a mechanic himself says my mechanic is not making sense and he is trying to take my money. Any ideas why the white smoke is still there??? Please help!!
07 Altima.
Was the head checked for warpage or machined before it was reinstalled?
Tester
And mileage.
Its a 07 nissan altima, 2.5s, the mileage is 80 @auto-owner
Idk my boyfriend was taking care of all of this and he trusted his mechanic, I really dont know that answer. @tester
You need to find out if the head was checked for flatness before it was reinstalled. If not, it could explain everything.
Tester
And if it was? What other things can be wrong? @tester
If the engine uses torque-to-yield head bolts, and the head bolts are reused it can also cause this problem.
Tester
I’ve read online that it can probably be anti freeze residue that I would have to drive the car for a bit in order for it to come out? Is that right? @tester
No.
If the head gasket repair was done correctly there should be nothing coming out of the tailpipe.
Tester
Ok thanks! I am going to see the car in the mechanics tomorrow and I will ask all these questions. Thank u again @tester
If the cause of the head gasket failure was overheating then piston ring damage is entirely possible and can possibly cause smoke which may appear to be whitish in color.
Before doing the head gasket both a dry and wet compression test should be done on all cylinders as an aid in diagnosing a ring problems.
If the car were mine, a dry and wet compression test would be done first just so I knew where I stood with it.
The mechanic said the piston rings are damaged, then he changed it to the cylinders and back to the rings. When I told my friend mechanic he said if it were the piston the car wouldn’t run and it would have a blue smoke not white. @ok4450 @tester
The piston rings are on the pistons. The pistons fit inside the cylinders so damage is usually mutual. If the rings are heat damaged then the cyinder walls could also be glazed at the least or scored at the worst; IF overheating was involved.
Sorry to disagree, but sometimes burning oil can come across as white in appearance due to heat from the converter.
It’s also assumed that an engine with an overly rich running engine (meaning too much gasoline) will belch black smoke and that’s not always true. Sometimes that can come across as blue.
Personally, I would never touch an engine for a head gasket only that was overheated (if that’s the case here) without a compression test first.
A head gasket weepage problem is one thing, but a gasket leak due to overheating is entirely different.
Just my 2 cents.
I don’t know about anyone else, but when I remove head(s), I do a through visual inspection of the cylinders/pistons to see if it’s worth bolting the head back down.
Tester
So let’s say it is what my mechanic says, the piston rings. How much would that be around? Is it even worth fixing? @tester @ok4450
07 Altima, 80k miles is still worth 8k. Might even be more. It’s no Honda accord but it’s an ok car. U need to pull head again, and than remove pistons to change rings. Don’t know if oil pan can be removed in car? U need to pretty much take entire motor apart to get pistons out. If u did the work, it would be ok but paying a shop XX dollars is a bummer. So, u check heads for flatness, replace rings, check cyl walls, replace pistons? It still might be fuel issue? People have done much more to cars and still had smoking issue.
Just went to look at the car and drove it a little, there was tons of smoke coming out and once I go past 25 the engine makes a noise. @tester @ok4450 @cavell. I went with my friend who is the mechanic and he says its the transmission.
Was this engine severely overheated before the head gasket gave up and was the engine barely running?
Do you know if the engine oil contaminated was engine coolant and whether or not the oil was changed after the head gasket job? If the oil was not changed, then anything done is suspect.
If piston rings are a problem a proper repair may not be economically worth it as doing it right usually means a complete engine overhaul.
The noise could be anything but coolant contaminated engine oil can ruin crankshaft bearings, piston rings, valve train components, etc.; meaning back to the engine overhaul scenario.
If the smoke out of the exhaust doesn’t clear up in a few minutes then there’s a problem with either the way the head gasket was done or the piston rings. This all goes back to the reason I gave earlier about running a compression test before doing any repairs and making sure the engine is salvageable before spending money on it.
As to the transmission, I have no idea why that is mentioned unless chronic severe engine overheating was involved and it fried the transmission fluid which in turn damaged the trans. It’s also possible that the transmission could be acting stupid because the engine is flat worn out.
I asked the mechanic and he said that he did to the compression test and that’s when he realized the rings were done. As far as the engine being worn out? How can that happen with a 2007? Is it because the person who previously owned it didn’t maintain it well? @ok4450