92 190E valve job and still have to put oil?
 

I recently got a valve job, around mid-late last year, because I had to put oil every 500miles.
The mechanic stated that it was probably needed a seal replacement. However, he said that to do the complete job and ensure that I don't have to put oil anymore he recommended a valve job. Expensive!

So I decided to get one.
Well, the first oil and filter change, I didnt' have to add oil. He used 20-50W.
The next time, I changed the oil and filter and used 5-30W. After 1000 miles, I had to put oil.
Now he is saying that it is the rings that is causing the problem, since it has so much miles? He recommended I use a heavier weight oil. So I used 20-50W.

Did he rip me off or not? Is he telling the truth?
I did use 20-50w the last time and that seemed to last longer. I had to put oil after 2500miles (I think it was 2500miles???).

Joseph

What did he do exactly? Valve guides, valve stems, etc.
How did he do it?
Is the head gaskette leaking?

I don't know what work was done, but I would not use 5W-30 in a 13 yr. old car operating in So. Cal.

use 20w/50

If it uses a quart every 2500 miles I wouldn't worry about it...... I own or have owned 3 300e's .... all of the old service records indicate 20w-50 was used.

What I meant by seal replacment was valve stem seals.

It needed stem seal replacement and he did a valve job since the job would replace the stem seals also.

Joseph

I completely agree with you. ;)

Valve job means different things to different folks. Do you know with certainty if he also changed the valve guides?

If he didn't, that could very well be your problem. His might tell you he did, but........................................

Yes, he changed the valve guides also.

Joseph

Actually, I recalculated the miles and it is 1800miles instead of 2500miles.

Anyways, during the first oil change, I didn't have to put any oil? Now I do?
What gives?

Joseph

Do any change, using 20w-50. If you still need to add some before 2000 miles, I'd worry.

So should I take this guy to court?
Basically, he asked me how many miles does the car have. I told him 200K. Now he is telling me it is the rings. Since it has lots of miles on it.

I ask why didn't he tell me that before I got the valve job?

So should I take him to court?

Joseph

When mine was new it used a quart every 2500 miles, and increased to about a quart every 2000 at about 3 years/35K miles. Mercedes agreed to install the updated viton valve seals that went into production circa 1990, but I decided to wait until just before the end of the 50K warranty. Just before that the head gasket started seeping on the exhaust side, so they ended up rebuilding the head - all new guides, new exhaust valves, and, of course, the updated viton valve stem seals. Note that this is more than just a "valve job". It's a complete cylinder head rebuild.

When all was done it used a quart every 2000 miles. So your car has 200K miles and consumes a quart every 1800 miles. What's the big deal.

My previous '84 190E 2.3 only used a quart every 4-5000 in the 50K miles I owned it before buying the 2.6. The sixes are higher speed engines, and they consume more oil.

Use 20W-50, drive it, and add oil as required.

Duke

Duke,
The big deal is that I they told me that to fix the problem (adding a quart of oil) a valve job is needed. I paid almost $2k for something that wasn't fixed. Had they told me that it may not fix the problem since the rings maybe worn and it has high miles, then I probably wouldn't have gone ahead with the VJ.

Joseph

All engines consume oil. A quart every 4-5K or more is great. A quart every 2K is so-so, but within normal limits, especially on these Mercedes inline sixes. So you started at a quart every 500 and now it's 1500-2000. If it were me, I would have ordered a valve seal change, which is relatively inexpensive. Once the valve springs are off a good mechanic can tell how much valve guide wear is evident, and at that point you decide whether to just continue with the seal change or pull the head for overhaul.

If the shop told you that a "valve job" would eliminate oil consumption they are either fools or shysters, or maybe you just misinterpreted what they said. All engines consume oil as it is needed to lubricate the valve guides and rings and a little always slips past. It's a matter of what is acceptable, and I would not consider major work (especially on an old car unless I was restoring it) until consumption got down to well under a quart every 500 miles.

A friend of mine bought a new 911SC in 1979. It consumed a quart every 600 miles, which seemed high for a new car, but PCNA insisted that this was within the normal range for this car and refused to do any work under warranty. He drove the car about 25K miles over a six year period and the oil consumption was about the same when he sold it.

Duke

Is there any smoke coming out the exhaust? That is typically the first sign of worn rings. You could hold a paper towel over the tailpipe for half a minute and see if it looks/feels/smells oily.

IMHO, a quart of oil every 1800 miles on an engine with 200k miles is not bad at all. It's certainly better than the 1qt/500 miles before the valve job. I also don't think the garage would have easily been able to tell that some oil was getting past the rings when so much more was coming past the valves. I'd have to say that you got what you paid for. Further, what you didn't pay for was a new motor, although it seems that you're expecting similar results out of your 200k motor.

/soapbox

Oil consumption after valve job
 

To determine the condition of the piston ring seal--do a compression check--first 'dry' and then with a tablespoon of oil added to each cylinder and cranked a few seconds before checking. If the two measured pressures are reasonable close (10-20# different) ring seal is good. a large difference indicates leaky ring seal.

With 5W30 oils, you can (and in So Ca-will) lose up to 20% of the oil from EVAPORATION, especially with 'conventional' lube oils. 5W30 is too light for that climate. 20W40 or 20W50 is much more appropriate.

Duke,
When I took it to them they said to it would need a VJ. However, I asked them how about a valve stem seal? They said, in order to do the job properly and complete, especially with the mileage you have, we recommend a VJ. They also said that if they only do a valve stem seal replacement and later it is still consuming oil, then i'd have to spend more money to do a VJ. So they recommend just doing a VJ.
Also the mileage didn't really go from 500-1200. At 500 I was using 5W30. Had I been using 20W30 I would change every 1200 miles. So technically it went from 1200 miles to 1800 miles.

Joseph

What can anyone say? Always get a second opinion and query the forum for opinions first.

Duke

When I bought mine at about 75,000 miles it burned a quart of 10w30 every 700 miles. I switched to 20w50 and its been at a quart every 1200 miles ever since, although lately it seems like its creeping up a little. I changed the valve guide seals and that didn't change anything, except I got an excuse to buy a compressor.

Thanks for this thread
 

My 92 300TE had the head gasket and valve seals (no guides) done at 90 kmiles. I bought it with 120kmiles. It has 145kmiles now. Since I've owned it it burns about a quart in 1000 miles. I was thinking about giving it a valve job in the near future but I'll stay away from that after reading this thread.
Bruno