Jump to content
  • When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.

Break in of a M10?

Recommended Posts

I´m just about to break in my 2002, M10. New cam, rings and bearings.

Whats the best way to do it? Easy-going for a while? For how long? Revving with not too much load? Or the hard way, as they do it with more modern motors? Supposedly a good way to go, but maybe not with a 60´s construction..


Ola Gustafson
1975 Taiga Euro 2002 3685483 - Weber 38/38 DGMS - Pertronix Ignitor - H&R Cup Kit - TEP headers and Simons 2" sport exhaust - 3.91 LSD.

Link to comment
Share on other sites

readjust the valves in 20 miles

vary your speeds, don't cruise at the same speed,

stay out of FULL THROTTLE untill 600 miles - and oil and

filter change, and another check of the valves


'86 R65 650cc #6128390 22,000m
'64 R27 250cc #383851 18,000m
'11 FORD Transit #T058971 28,000m "Truckette"
'13 500 ABARTH #DT600282 6,666m "TAZIO"

Link to comment
Share on other sites

I'd recommend a zinc additive in the oil for cam wear in...

I agree X10 if you have a new cam and/or rocker arms you need a break in additive or you will damage them both!!!! Then just drive it. Vary the engine speed (don't just get on the freeway and sit at one speed) Retorque the head after 100-200 miles. Run the break in oil for at least 500 miles, if you are worried about dirt change the filter earlier but you should be ok oto 1000 mi. at 1k change the oil, torque the head again and check the valve adj.

1970 1602 (purchased 12/1974)

1974 2002 Turbo

1988 M5

1986 Euro 325iC

Link to comment
Share on other sites

Several schools of thought here.

Recommend either organic Motorcycle oil or organic diesel engine oil (Duramax) in the appropriate weight (both heavy w/ ZDDP).

Method #1 - Baby the engine, varying rpms for 500-1000 mi.

Method #2 - Run engine, in neutral - stationary, at 2500 rpm for 5 min. and then up the throttle to 3000-3500 rpm for 15 min. (recommend placing window fan on high in front of radiator).

After either of these, drain oil, swap filter, re-torque head, and fill with your juice of choice.

I've rebuilt several motors (Lotus 910, Datsun L24, Coventry Climax, BMW M42) using both methods and each gave excellent service for at least 75k+ miles (sold the cars around this mark - no reported failures from new owners).

Assume you used assembly lube. If not, use a drill powered pump to charge the oil galleries and 'float' the crank prior to starting - check oil pressure gauge if available.


1976 BMW 2002

1990 BMW 325is (newest addition)

1990 Porsche 964 C4 Cabriolet

Link to comment
Share on other sites

stay out of FULL THROTTLE untill 600 miles

or, if you believe the ring guys, get it open as SOON as it's warm,

and get some pressure against the rings to get them to seat

onto the bores.

There are several different components in a 'new' engine, and they

all want different things.

The cam wants lots of oil, and moderate pressure- thus, 2500 for 20 minutes.

The bearings SHOULD not touch anything- but if they do, they want light


The valves themselves don't want to get all that hot to avoid galling

onto the seats. Especially the exhaust.

The rings want lots of pressure to wear them into the bores, and thus

make a good seal to the clinder walls.

For a street engine, I have had good luck with the 'warm it up

at 2500, then take it out and run it (at large throtte openings)

from 2500- 4500 and then let it engine brake a bit.

That's just me.


"I learn best through painful, expensive experience, so I feel like I've gotten my money's worth." MattL

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
  • Upcoming Events

  • Supporting Vendors

  • Create New...