blue smoke after valve job - PeachParts Mercedes-Benz Forum

llm4 · #1 10-19-2011, 09:55 PM

1983 617 turbo, 175k miles. Leak down test poor with most of air leakage coming from turbo. I pulled head and had a valve job done on head (new valves, seats ground, seals, and new valve guides).

After replacing head and 2,000 miles, now I have blue smoke from exhaust and using oil. I pulled head again and found valves with more than normal oil on port side of intakes and burnt oil on exhaust valves. Intake manifold had no oil in it. One thing that doesn't look right is the new valve guides. They is large grove where the valve seal goes (see pics) and the valve seals don't have matching "rib" to go in the grove. Seals don't appear to fit very good. Are the guides not the correct ones or upside down? Do you think I have other problems? Also, the dark red seals were installed on the exhaust valves.

Thanks in advance!

leathermang · #2 10-19-2011, 10:40 PM

Are you saying that you do not think the new ' gas lip ' seals were used ?
I thought that all valve seal kits were going to have the same color for both valves for the turbos.... ?
What kind of tool was used to install them ?
If that is all that is wrong... that is not fatal to the work which was done.... you just take down the valve assembly.... sorta a valve lash setting on steriods job.... and install them...then put back together..
Were NEW valve springs installed ?

Diesel911 · #3 10-19-2011, 10:41 PM

I do not know if it is my Computer or not but I could not view your pictures.

leathermang · #4 10-19-2011, 10:42 PM

The only pics I could view did not show the red seals.....looked like pre work pics...

Diesel911 · #5 10-19-2011, 10:56 PM

I used the below Meistersantz brand Vavle Stem Seals with no issues (cost about $16 per set).

Was there any Oil in the intake manifold that would indicate the Turbo Charger was leaking Oil?

It is a shame the Valve Stem Seal issue was not noticed before pulling the Head off as the seals could have been changed with the head in place.

Looks like it is my computer; as I cannot view the pic I posted.

t walgamuth · #6 10-20-2011, 05:32 AM

Are bronze guides factory? I was thinking they are Iron.

If those are after valve job pics there certainly looks to be a lot of oil in the ports and around the valves.

wildest · #7 10-20-2011, 09:31 AM

Quote:

Originally Posted by llm4

1983 617 turbo, 175k miles. Leak down test poor with most of air leakage coming from turbo. I pulled head and had a valve job done on head (new valves, seats ground, seals, and new valve guides).

Did the leak down test indicate that air was coming from the turbo side, ie. intake valves? If you are burning oil after 2000 miles on a recent valve job, and the bottom end is tight (rings show minimum leakage), then there is something wrong with the valve job or the turbo seal may be leaking now.

whunter · #8 10-20-2011, 11:12 AM

The valve guides are damaged.

It appears they may have been held by pliers = gouged the exterior sealing surface.

NOTE: The seals are installed using the plastic protective tube on each valve, and with hand pressure only, not hammered on.
Failure to use the protective tube and/or hammering the seal on will damage or destroy the seal.

.

llm4 · #9 10-20-2011, 11:13 AM

pictures are current, I just took apart (second time).

Leathermang,
-The valve seals were bought from an online MB dealer, I was assuming they were correct. They are smooth inside, no lips or ribs.
-The colors are dark red and bare metal color (not red & green).
-No tool is needed, they push on with a little pressure.
-No new springs, but were tested according to FMS and were ok.

Diesel911,
-The intake was dry, no oil residue. I'm taking the turbo to be checked out today.

t walgamuth,
Yes these are current pics after 2000 miles. A lot of oil.

I just got my new valve seals from the same company and they are the same as the ones I just took off.

Thanks! Have more pics if needed.

leathermang · #10 10-20-2011, 12:31 PM

All I can go by is what my paper manuals say.... and the gas lip seals back then were the ones which were the upgrade and into the future ones to use... they could have been changed by MB ...but to me the gas lip were clearly the better sealing type.... ask Whunter... he should have the latest info .....but I would be surprised if you are supposed to have the non gas lip seals on a turbo engine... even the NA engines were being changed to that as the recommendation.... perhaps the wrong valve guides were installed making the gas lip seals not usable..

While certainly " hammering " while installing the valve stem seals is not appropriate.... a good hit with the flat of the hand ON THE FACTORY SPECIFIED INSTALLER is justified enough to seat the gas lips.... as per the FSM....

leathermang · #11 10-20-2011, 12:36 PM

Quote:

Originally Posted by llm4

...No tool is needed, they push on with a little pressure....

LOL, and provide little sealing to match....

sorry, too easy,served up on a plate.... had to take that one...

The FSM shows an installation tool....sorta bends around the cam assembly to provide straight down push on the seal...and they warn to check to see if the lip catches....

1960mog · #12 10-20-2011, 02:01 PM

I have never seen red valve stem seals for this engine.
Please post a pic of them if you can.
The green and black ones should be used.
Unfortunately the brass guilds are all you can get this days.
Make sure the guides are tight in the head by tapping them lightly with a hammer and a drift.
The brass guides have to be reamed after installation. Maybe they where reamed out to far.
Also the intake guide has to be longer then the exhaust guide.
I wish I could still buy the original cast iron guides.
They much easier to work with.

Stretch · #13 10-20-2011, 02:13 PM

Quote:

Originally Posted by 1960mog

...
I wish I could still buy the original cast iron guides.
They much easier to work with.

I'm like 95% sure I got cast iron ones fitted last year. When I saw the OP's first picture I thought "oh wow those are nice and shiny I haven't seen those before"...

leathermang · #14 10-20-2011, 04:03 PM

Quote:

Originally Posted by 1960mog

.....The green and black ones should be used.....

Without going to look ...that was my impression of the colors available...and my book indicates only one color was going to be available in the future.. basically they were going to use the one for Exhaust on both in the future...
Bronze is a long used material for valve guides... so done right they should be ok...

whunter · #15 10-20-2011, 05:00 PM

Quote:

Originally Posted by llm4

pictures are current, I just took apart (second time).

Leathermang,
-The valve seals were bought from an online MB dealer, I was assuming they were correct. They are smooth inside, no lips or ribs.
-The colors are dark red and bare metal color (not red & green).
-No tool is needed, they push on with a little pressure.
-No new springs, but were tested according to FMS and were ok.

Diesel911,
-The intake was dry, no oil residue. I'm taking the turbo to be checked out today.

t walgamuth,
Yes these are current pics after 2000 miles. A lot of oil.

I just got my new valve seals from the same company and they are the same as the ones I just took off.

Thanks! Have more pics if needed.

You have e-mail.