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Posted

when valve stem seal leaks, does it cause blue smoke at every cold start? or can it be on and off thing? i.e. does it show up consistently or not?


Posted

The valve stem seals can be replaced without removing the heads by pressurising the cylinders with the valves in the closed position. this could save considerable money, however the valve guides could be worn and might cause failure of the valve stem seals again , it is a crap shoot. I had the seals replaced on a Mercedes 190E for less than $250 by a very respected german car garage nearby, It quit using oil, but lasted only a year. I then ended up rebuilding the engine. Lower end was fine but the head and the valve guides were bad.

Posted
The valve stem seals can be replaced without removing the heads by pressurising the cylinders with the valves in the closed position.  this could save considerable money, however the valve guides could be worn and might cause failure of the valve stem seals again , it is a crap shoot.  I had the seals replaced on a Mercedes 190E for less than $250 by a very respected german car garage nearby, It quit using oil, but lasted only a year.  I then ended up rebuilding the engine.  Lower end was fine but the head and the valve guides were bad.

In my situation, I could likely go at least another year by using the strategy suggested here and advised by my own mechanic. I am relatively confident that my mechanic is giving me a worst case scenario that would be modified downward (costwise) by what he finds when the time comes to actually open her up. Much is based on her mileage and age. It is ALL a crap shoot with a car this age as the transmission and other mechanical parts are still really good (knock on wood) but who knows in a couple of years?

I have never had cause to be concerned about being oversold. I would rather fix it good the first time even if it costs a bit more than a patch up. Obviously, if I expected this car to be new again, this is unrealistic. Ultimately, the car is an old car and it will last only so long. So, I asked him what rebuilding the engine would cost without giving him any opportunity to check compression or anything. That sounds like excellent advice and I plan to take it. Had I known about it yesterday, I would have had it done at the same time as the IAC cleaning and oil change.

thanks

rosie

Posted

So, we took her out for a ride on the freeway yesterday (blew the soot out of her, I guess) Today, no blue smoke or smoke of any kind on start up!

Take a bow, ToysRMe.

rosie

Posted

Thanks! About everyonee on here would have told you the exact same thing. All I did was beat them to telling you!

I think you'll be set for life when it comes to car problems now! (Or anything in generally really!) Just handle it exactly like you did & you're golden!

Good luck with it! If it starts smoking more often remember to troubleshoot yourself (cause you're good at it) Then worry hubby with it. Don't forget that what worries you, worries hubby & what worries hubby get's a smacking!

  • 9 months later...
Posted

I didn't mean swap the engine yourself!!!

Right now I can only think of one woman I would trust could do an engine swap herself.

rip-strut4.jpg

Hi babe~!

Like the guys were saying in the start of the post, it's probably your valve stem seals because you only get some smoke when the engine cranks. When valve stem seals go bad, you just get a few drips of oil here & there. Just enough so that when you stop the engine & turn it back on you'll see smoke. (The leak itself is so slow you don't get any smoke while the engine is running normally.)

********************

Skip this if you want. In a nut shell, here's what we say your problem is.

If you need to know a really down to earth explanation of how the engine works.

http://auto.howstuffworks.com/engine.htm

Is awsome. The flash animations say everything 4-7th grade science does, 'cept you won't sleep through it & it takes a few min to glance through at most! LoL!

What happens is oil flows up to the top half of the engine to lubricate moving parts. (In our case the camshafts & related valve equipment.) Look how everything in my front head had the pretty golden tint to it. That's from oil.

oil-on-cams.jpg

Now on the underside of that is where the good stuff takes place. It's the top part of the combustion chamber & houses the valves that let air in & exhaust out.

(You can see the 4 valves per cylinder)

MVC-014F.jpg

Here's a cleaned valve.

Lapped-IntakeValve.jpg

Take the valves out & you see the hole<s> they fit into.

NoValveChamber.jpg

Obviously, those holes have to run from the top side to the bottom side. Here is where the problem lies.

On the one hand, you've got steel valves going up & down in a metal hole. Metal rubbing metal is very bad! To fix that you let oil fall into the hole to lubricate everything. The bad news is that now that oil is flowing through holes you have to seal it so oil doesn't leak out. That's what valve stem seals are for! They are just little metal caps with a rubber ring to seal the oil from dripping out.

valve_seals2.jpg

Those 4 nasty looking holes from before. You slip a stem seal over it then put the valve in.

So what's the big deal? What happens when oil drips by? It falls directly on the valve into the combustion area where it burns up with the gas & you get a smokey engine & some oil loss. (normally bearly measureable)

********************

With the mechanic quoting so much for a rebuild, I'm pretty sure he's saying let's take the whole thing apart. I honestly don't trust the quote either way he means it.

1) Because of the symptoms you gave us & previous common experience tells us that another possible cause - piston rings - are not likely your problem. (Which ya, I can see 4 grand for rebuilding an engine bottom to top. That's in line.)

2) If he's saying $4000 to replace the valve stem seals I don't think that's right. Even if he did things like general maintenance items & then did repair work far above what "the book" tells you to do - You'd be paying over $3000 labor charges of your $4000 spent just for him to do a few hours of work & keep your car!

Neither of those reasons mean that he (or anyone else) is right or wrong. I's just why I don't trust it.

Now if the mechanic did compression, or leak-down tests on the cylinders & it showed the rings were leaking. That's fine - we're off to the races tearing the engine into itty-bitty-pieces!

My other point was that if it were me & I was staring over $3000 worth of engine work in the face. I simply wouldn't do it. Instead of rebuilding it, I would buy a lower mileage engine coming out of Japan - have it shipped to an honest mechanic (or at least a good one!) - and have them swap the engines. It would be much cheaper even after doing all possible maintenance on it, and checking it after it's been installed!

Ebay search 3vzfe

Ebay search 3vz-fe

Obviously you don't want to buy one that looks broken! :lol:

Anywho, before anything get's done in the future, I would get a compression test, or a leak-down test done. (Get them to write down the numbers too!) That way you know exactly what & where the problem is & you know exactly about what the cost is going to be before a mechanic can see your car.

I like you, you're smart. You've done everything exactly like you should.

1) Narrow down the problem<s>

2) Find the cause<s>

3) With the information learned, use it to fix the problem<s> in the most fitting way.

Thank you for this information.. This help me understand about the smoke and the valve seat / stem!

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