any m103 owners go past 150k miles without valve job?

[momentum]

I was wondering If there's anyone here that has a m103 engine with 150k miles or more thats still hasn't had the valve job done yet? How do you know when to draw the line? When smoke starts coming out the tailpipe?

[haasman]

momentum

Our '91 300E just turned 200k and no valve job. I did recently discover the front cover seal is leaking.

I can't tell you why it doesn't need a valve job except that I bought it used a couple of years ago and it was very clear it was well maintained. A previous owner maintained through 124k miles at a dealership. It is without a doubt one the best cars I have ever owned. It looks great and really runs well.

I think the keys to avoiding the valve job are the following:

-Frequent oil and MBZ filter changes appropriate to kind of driving.
-Use quality oil of the right viscosity.
-Driving off conservatively until the engine warms, especially after sitting a while.
-Avoiding over heating at all costs.
-Drive it very hard occasionally, going into high RPMs until close to redline, only after warmed up)

I would pull my car off the road if I saw smoke coming out the tail pipe. Often it seems it is oil consumption not smoking that makes people do a valve job, and typically coming first from valve guide seals, then worn valve guides and then and a distant last, bad or worn valves.

I believe I read on this forum that in the year 1990 MBZ changed the valve guides and the valve guide seals, which are longer lasting.

Do you think your engine is due?

Haasman

[momentum]

My 87 300e has 135,000 miles and all 6 plugs have oil on them when i pull them out. I was hoping to just get the seals replaced but my local mechanic advises on the $1200 valve job. what ya think just a way for them to make money?

[haasman]

Hmmm good question.

Here is what I would do. I would first change the oil and put in MaxLife oil, at least a 10W-40. This oil supposedly "conditions" the valve stem seals. I think it does. It could start reducing the oiling problem IF is coming from the stem seals.

If that didn't work you could go for the stem seals, but many argue that for the approx $300-400 it would be better to do the head. You would get new stem seals, guides, head gasket and a valve job. BTW, the bottom ends of these engines are remarkable. Often with 300k the cylinder walls look like they have hardly worn.

I can't tell you about your quote. It isn't out of line, it maybe right on. If I were to decide on the doing the head completely, I was *absolutely* make sure the latest guides, stem seals and head gaskets from ONLY Mercedes were being used.

Hope this helps, let us know,

Haasman

[ctaylor738]

199K and compression is fine, but needs seals - quart every 800 or so. No oil on plugs and cannot bring myself to pull the head off an engine that runs perfectly.

Sure, I pulled the head at almost 180,000 miles, but it was because the PO had not changed antifreeze regularly and it corroded between combustion chamber and water jacket. Up until that time it used no oil and ran perfect.

That was over 50,000 miles ago and all is well.

All that said, pulling the head to do a valve job is not a totally bad thing. The bottom ends of these engines are incredible. The head comes off and goes back on well and the results are predictable.

It was not that long ago that engines on most any other make car, particularly American, were doing really well to make 150,000 miles before a COMPLETE OVERHAUL. Given that doing a valve job and getting another 150,000 miles or more makes for a pretty darn good engine.

My $0.02,

[taaboo]

1989 300TE, 186,xxx miles, purrs like a kitten.

Had valve seals done around 100K but I think we were ripped off.

Mobil 1 every 7500 miles or twice a year.

Brian

[mplafleur]

Had gone 220,000 miles before timeing chain broke, therefore forcing me to do the valve job.

[stevebfl]

VALVE SEALS not VALVE JOB. Anything further is wasted!!!

Proper servicing of that motor should have seals going on about every third 30k service. It would add marginally to the service and solve all consumption problems before most arose. I have seen many a 103 only go 60k on valve guide seals.

[adrianruk]

My '88 300TE with 103 engine has done 265k miles with no attention to valves. I am the 2nd owner & have detailed service records from 11k. Timing cover oil seals done at 128k (still weep a bit though). I replaced the hydraulic lifters at 132k due to a couple of noisy ones. Otherwise only routine servicing ( oil & filter at c6000m). No visible smoke from exhaust though it uses about a litre of oil every 1000 miles or so now. Plugs stay clean between changes and it never misfires or fails to start first touch. Still runs quiet as a mouse and has as much power as my 300TE-24 (with 104 engine) up to about 4500 rpm. The 104 is far noisier, thirstier and temperamental.
Give me a 103 in preference to a 104 any day!
Adrian

[blackmercedes]

Our 1990 190E 2.6 has 340,000 kilometers (212,000 miles) and the head has never been off. Runs like a top, uses little oil.