M42 reliability and high mileage

[Vicarious]

Hey guys, i'm shopping for an M42 318, and i've seen some for very good prices, but they have high miles, as in 200-230k. The owners say they've replaced a lot of stuff, like water/fuel pumps, t-stats, radiators, etc, all that preventive maintenance goodness. Now i know that the M42 has forged internals and is one of the strongest engines, but how strong. Should i stray away from the ones with 200+k miles?

[e30_kid89]

around that mileage, i would automaitcally consider that the timing chain,rail,guides etc and tensioners will all need to be overhaule'd. also check the oil sump becauce they are know for falling out and sitting in the lower oil pan leading to engne destruction.

[Vicarious]

how much do you think that stuff will run me? From what i've read those things can be done by ones self easily.

[jrobie79]

how hard is it to change the timing chain by myself? and whats the cost of a new one. my car is 222K on it i bought it with 180 so im thinkin about taking a look at some of the stuff u mentioned.

[BrandC]

Brendan Percel's (spelling?) webpage is the most excellent 318i/is resource. It is filled with DIY's for anybody decently mechanically inclined. He also rates the difficulty levels of tasks like Pelican Parts DIY's.

The M42 is a very easy engine to work on, you will have fun doing the work yourself.

[jrobie79]

whats the URL for that site?

[Funkmasta]

If you find a motor with that mileage, don't immediately discount it.
I just this weekend, saw a nearly 300k non-rebuilt M42 just lay down 220-190 in every cylinder.

[frost_dxb]

300k is just mid life they are strong engines with forged Con-rod and Crank

[Simon S]

BP's BMW E30 318is Site

stellar resource.

[strad]

Mine has 195k with no chain noise (just installed a new M44 tensioner). Had the lower pan off and all the bolts were tight too. Pulls strong. I'm thinking about selling my 2000 mustang, which though very well maintained is turning into a POS at 90k miles, and keeping the little M42. The wife likes the M42 because it's red! :)

[golde30]

you guys should see the 226K miles m42 that was in the 318is i bought. that thing looked like some1 put a grenade on top of the #1 piston. i believe it dropped a valve, and the PO decided to keep driving it as long as he could till it just stopped moving.when i dropped the oil pan, there were HUGE chunks of metal in there. ever since then i have been scared of driving my m42 hard, i baby the shit out of it. my m20 on the other hand, gets driven quite hard...

[NOMAD]

Do NOT let them overheat. From what I read it's a really strong engine but dayum if mine didn't just take a dump. The little plastic water pipe under the intake manifold cracked, dumped coolant out and the engine overheated. I replace a bunch of hoses etc but the damage was done. I'll find out tomorrow if it's a warped headgasket or a cracked head.

There are a few nitpicky issues with these engines, the later M44 has all the kinks worked out from what I see.
No more issues than other cars like it but issues nonetheless.


Get the best condition engine you can find, then still plan on replacing critical components and DO NOT WAIT. Once you take care of hoses, vacuum lines, water pump, t-stat, timing chain, chain tensioner, fluids, gaskets etc you should be really happy.