Just out of curiosity- who knows how much a ring job would run on an m103 engine?

And if I was to tackle this myself in the near future, what skill level are we talking about? I'm pretty sure my piston rings are worn due to the smoke coming form the valve cover breather tube.

Thanks

I doubt your rings are bad, most likely valve stems/seals. If your rings are in fact bad, you would be better off buying a junkyard engine.

The bottom end of the m103 NEVER goes bad unless you run it without oil

__________________
Eugene

10 E63 AMG
93 300te 4matic
07 BMW X3
14 Ford F-150 Fx2

That would be pretty damn spectacular, I hope you're right. If it is the valve stem seals, is that affordable and easy to do?

M103 valve stem seals go bad eventually. See the resources tab above, someone wrote up a how to in the DIY articles.

__________________
2006 BMW M5 "Heidi" @ 109,000 miles
2005 MBZ C55 AMG "Lorelai" @ 165,000 miles
1991 MBZ 300E "Benzachino II" @ 165,000 miles
1990 MBZ 500SL "Shoshanna" @ 118,000 miles

(On the hunt for a good used M103 engine as of 6/10/23, PM me if you have one to sell!)

Much cheaper than piston rings! If you are not 100% sure, take it to a mechanic. In fact, for $120 bucks, you can get it diagnosed by the dealer.

How much oil are you using?

__________________
Eugene

10 E63 AMG
93 300te 4matic
07 BMW X3
14 Ford F-150 Fx2

Found it. Never noticed that resources link. Thanks for pointing that out!

http://en.wikipedia.org/wiki/Leak-down_tester

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1992 W201 190E 1.8 171,000 km - Daily driver
1981 W123 300D ~ 100,000 miles / 160,000 km - project car stripped to the bone
1965 Land Rover Series 2a Station Wagon CIS recovery therapy!
1961 Volvo PV544 Bare metal rat rod-ish thing

I'm here to chat about cars and to help others - I'm not here "to always be right" like an internet warrior



Don't leave that there - I'll take it to bits!

Changing valve stem seals will have no effect on the OPs concerns.
@ OP-Some "smoke" is normal. If that is the only issue then it's likely you really have no issue.

I'm not really sure how much oil I use. I usually check my oil every month and it falls in between the two marks on the dipstick pretty consistently.

Here's a video, maybe you guys can tell me if this is a problem or if it's normal. This is from a cold start, so you can barely make out the smoke. It puffs out considerably more once it reaches operating temp.

http://www.youtube.com/watch?v=S-HUnON7jfQ

Thats nothing to be concerned with.

Just keep checking the oil, the m103 is known for leaks, and oil consumption.

__________________
Eugene

10 E63 AMG
93 300te 4matic
07 BMW X3
14 Ford F-150 Fx2

Wow, what a turn of events. I've always thought that blow-by meant worn piston rings. Nevertheless, thanks for the good news!

blowby is through rings..

But, the guides on early M103's were soft- they wear and age/head and loose guides cause failure of the valve stem seals. The vacuum on the intake stroke, pulls the oil through the guide and down into combustion.

M103's are not real leakers- mine's dry and it's had 1-2 v/c gaskets, re-seal the timing cover 2X, and the big o-ring on the oil level sensor once. 25 years of driving.



Michael