3.5L M30 engine

Drew20

Well-Known Member
Site Donor
Messages
465
Reaction score
136
Location
Beaconsfield
Sounds like a standard M30B34 engine, as fitted to 5,6&7 series cars from 1982 onwards. Can't imagine it's particularly rare. The team on bigcoupe.com might know more, as it's their era of M30

The M90 displaces 3453cc, as opposed to 3430 for the M30B34 and is rarer. The M90 came with either l-jet (and old style dizzy), or with early motronic (with the dizzy fitted direct to the front of the head)
 

Belgiumbarry

Well-Known Member
Messages
1,618
Reaction score
1,116
Location
Belgium
so i did a little search for later '80's 3.5L M30 engines …. let's say max 500 km away .... or already to "expensive" to just have a look.

Now , most ask 2000...1500 € , i even seen one asking 4500 € ! They all have the classic 34 6E A/B or C stamp , so nothing rare indeed , the common M30.
On none you are sure , all out of "a" car and "good" according sellers :)

So one must always take a risk i suppose , hoping for a good start and rebuild within the normal cost …. and not a engine for scrap….

@Gransin i'm afraid there are no longer 400/500 € engines for sale....:(

i think i take the one that's offered to me.... have the most confidence in it and ….we are at 1200 € :D
 

Gransin

Well-Known Member
Site Donor
Messages
1,528
Reaction score
1,271
Location
Vasa, Finland
so i did a little search for later '80's 3.5L M30 engines …. let's say max 500 km away .... or already to "expensive" to just have a look.

Now , most ask 2000...1500 € , i even seen one asking 4500 € ! They all have the classic 34 6E A/B or C stamp , so nothing rare indeed , the common M30.
On none you are sure , all out of "a" car and "good" according sellers :)

So one must always take a risk i suppose , hoping for a good start and rebuild within the normal cost …. and not a engine for scrap….

@Gransin i'm afraid there are no longer 400/500 € engines for sale....:(

i think i take the one that's offered to me.... have the most confidence in it and ….we are at 1200 € :D

Okay, I must say I haven't been following international M30 prices, I've mostly been looking at engines/complete cars here in Finland.
I did have an e32 735i that I planned ripping the engine out of, but the car was too nice to slaughter and I simply didn't have the heart to do it.. an enthusiast bought it and I'm back at square one.
Seems like I should start prioritising finding a good B35 + G265 before they become really expensive.
 

Belgiumbarry

Well-Known Member
Messages
1,618
Reaction score
1,116
Location
Belgium
Saturday i will get the engine.... think of injecting some WD40 and diesel into the plug holes , nice opportunity to soak the rings while vibrating on the trailer for a couple of hours. ( is in storage for at least 5 years )
After removing most aux parts i fill fresh oil/filter , hook up a batterie , do a compression test and see what the oil pressure does.... if that is all "good" i keep it the way it is to install "ever" … just have a look at the cam and secure the banjo's.... i have the double tap washers , just placed them on my 850i . Same danger :)

what would you do more ?
 

Markos

Well-Known Member
Site Donor
Messages
13,369
Reaction score
7,502
Location
Seattle, WA
I’ve read (I think on here) that ATF works well. I’ve never personally had to deal with a seized motor or one that sat for more than a year.
 

Belgiumbarry

Well-Known Member
Messages
1,618
Reaction score
1,116
Location
Belgium
thanks Markos, i can make a mix WD40/diesel ? /ATF... now, the motor is not "seized" , but i like to play it save before turning it over.... some rings can get "fixed" dryed/rusted in the carbon deposits , and do some damage before coming loose ( break ? ) , turning the engine … you never know after +5 years…..
 

Belgiumbarry

Well-Known Member
Messages
1,618
Reaction score
1,116
Location
Belgium
SAM_2634.JPG
SAM_2635.JPG
SAM_2636.JPG
SAM_2637.JPG
bought the '86 engine this afternoon, give it a good high pressure steam clean and demounted the injection stuff/alternator …, engine is turning very well , oil is clean, cam is perfect and no loose banjo's !
There was no starter motor anymore…. so i will have to look for one.
I ordered a engine stand and with a starter motor i can test compression and see for oil pressure…. i assume without plugs and a good batterie one can see 0.5 bar on starting a "good" cold engine ? Of course fresh oil and i need a oil cooler to connect...or plug it ?

so far good ! :)
 

Belgiumbarry

Well-Known Member
Messages
1,618
Reaction score
1,116
Location
Belgium
@sfdon 's tip i bought a sr444x starter motor. That could fit my 2 E9's and my 850i ! … just have to look how we can plug in the oil cooler connections with flexibels... ,not using the oem tubes , with which we can route / use any oil cooler ….

at the moment all pistons rings are soaking in a mix of WD40/ATF and diesel... but engine turns extremely well already. So i don't expect problems there after the 5 ( +) years storage …
 
Last edited:

Stevehose

Well-Known Member
Site Donor $$
Messages
12,934
Reaction score
5,598
Location
Sarasota, FL
I've seen it on some 5-series but not sure if OEM. Fits a Holley 4 bbl I believe. I'd hate to be intake runners 1 & 6.
 

Belgiumbarry

Well-Known Member
Messages
1,618
Reaction score
1,116
Location
Belgium
yes , don' know what the oem carb was but have seen it on the net changing it for a Holley ….
different lenght runners must be good for torque over the rev's range ?

IM1.jpg
IM2.jpg
 

Belgiumbarry

Well-Known Member
Messages
1,618
Reaction score
1,116
Location
Belgium
never seen that Robert , a marine version ! i see they use the camshaft at the rear to drive the sea water pump.
Wonder who made those parts…..
 

Gransin

Well-Known Member
Site Donor
Messages
1,528
Reaction score
1,271
Location
Vasa, Finland
never seen that Robert , a marine version ! i see they use the camshaft at the rear to drive the sea water pump.
Wonder who made those parts…..

Direct quote from Wikipedia:

"In 1977, BMW AG established a separate marine division, incorporated as BMW Marine GmbH. BMW Marine's head office and assembly plant were located in Verviers, Belgium.
BMW Marine continued to marinize BMW's production automobile engines. BMW's 2.0-litre, four-cylinder M10 engine became the B 130, and the M30 six-cylinder engines in 2.8 and 3.3-litre variations became the B 190 and B 220 models. Later, the larger 3.5-litre M30 with electronic ignition became the B 635. Model numbers related to the engine's horsepower"

Would be nice to have a BMW M30 powered boat;)
 

Belgiumbarry

Well-Known Member
Messages
1,618
Reaction score
1,116
Location
Belgium
postman this morning :D

now i must say , quality is beyond my expectation !
Primaries are 40 mm , end tubes 50 mm.
'Nice" TIG welded , inside grinded and polished , sure enough quality for a "cheap" header .
Perfect fit , no need to push or pull anything…. (have seen others).
Bosses and plugs for a dual A/F gauge .

The Schnitzer header on my rally coupe has bigger primaries , they start at the flange with the same (as the exhaust port ) but go bigger very quickly.
That would have been better for high rev's track use…. i assume this one here is even better for torque in rally/street use.

SAM_2655.JPG
SAM_2659.JPG
 
Top