Author Topic: Engine Building Advice (Read 7020 times)

E36m42 · « **on:** April 30, 2014, 09:22:11 AM »

So I sourced a late m42b18 for my 93 e36. I want to take it to a shop to check the head and bottom end to make sure everything is ok. I also want to change piston rings and crank shaft bearings. Basicly come out with a "new" engine. As this is my first time around the m42, what do you guys recommend to look for or put on the engine? Things like headstuds maybe small upgrades that are budget friendly? Let me know!

thebrelon · « **Reply #1 on:** May 01, 2014, 01:17:08 AM »

are you looking for any performance upgrade or "just" a rebuild?

I would also have a look a all the timing componant (chain, guides, sprockets, tensioner...), at the oil pump (check condition, clean), replace valve stem seals, new hyd lifters.

thebrelon · « **Reply #2 on:** May 01, 2014, 01:42:06 AM »

oh! and have a look at all the mess under the intake. even if you keep it stock it may be the time to replace anything damaged while you're at it!

E36m42 · « **Reply #3 on:** May 01, 2014, 09:25:53 AM »

I'm looking to rebuild but I have seen some builds that members have done and they are pretty awesome. With that being said someof these builds are pretty costly! So I just wanted to know when it comes to things that should be done what are they which you have answered. Then what are things that can be replaced with better parts that arent costly but are good things to do in the process of rebuilding the engine.

thebrelon · « **Reply #4 on:** May 01, 2014, 01:45:07 PM »

well then somebody may say better than me as I've not yet looked at it but bearing can be replaced with better ones from BMW. ones with 360� lub groove if I'm right. don't know from which engine, 318tds if I'm right...

e3091318is · « **Reply #5 on:** May 01, 2014, 04:02:18 PM »

Just make sure you don't half-ass it if you plan on keeping the car for a while. deck the block and have everything done right the first time.

e3091318is · « **Reply #6 on:** May 01, 2014, 04:04:19 PM »

Quote from: e3091318is on May 01, 2014, 04:02:18 PM

Just make sure you don't half-ass it if you plan on keeping the car for a while. deck the block and have everything done right the first time.

If you bring the engine to a shop yourself and let them know exactly what you want done, it shouldn't run you more than $1500. I have a valve job, all machining (deck, honing, resurfacing), all new gaskets, bearings, seals, etc. Also some new pistons are always nice but that might run you another $500.

keflaman · « **Reply #7 on:** May 02, 2014, 05:12:02 AM »

Quote from: thebrelon on May 01, 2014, 01:45:07 PM

well then somebody may say better than me as I've not yet look at it but bearing can be replaced with better ones from BMW. ones with 360� lub groove if I'm right. don't know from which engine, 318tds if I'm right...

You're on the right track, however, it's almost any engine except the 318tds. http://bmwfans.info/parts-catalog/11211706847/

On some parts BMW defaults to the "new" or "improved" versions for our cars. In the case of bearings, you actually order a six cylinder set and use what you need. I bought an M20 bearing kit from Rock Auto when they had a manufacturer's closeout sale.

thebrelon · « **Reply #8 on:** May 02, 2014, 06:36:26 AM »

allright! thank you for the information!

thebrelon · « **Reply #9 on:** May 02, 2014, 06:48:21 AM »

Quote from: keflaman on May 02, 2014, 05:12:02 AM

you actually order a six cylinder set and use what you need.

I checked: they're the same on M43 engines which are 4 cylinders.

E36m42 · « **Reply #10 on:** May 02, 2014, 01:28:03 PM »

so if I understand correctly you guys say 6 cylinder crank bearings will work on the m42? and the 6cyl is it the m50 series or m20 series? Also as someone has mentioned should I do pistons also? if so which should I use. I honestly would want to put some boost later. Is it possible to build a bottom end now to rebuild the head with better specs later? If I wanted to go the boost route I would like to keep the m42 crank and maybe bore the cylinders which I have gotten a quote and wasnt that much to do. Just all depends on the pistons prices and what you guys tell me. It's my first build and I would LOVE to do it right

keflaman · « **Reply #11 on:** May 02, 2014, 09:16:41 PM »

Quote from: E36m42 on May 02, 2014, 01:28:03 PM

so if I understand correctly you guys say 6 cylinder crank bearings will work on the m42? and the 6cyl is it the m50 series or m20 series?

The number 4 crank journal was originally a "half" bearing from the factory and tended to chew up the crankshaft causing "crank walk". As thebrelon mentioned, The upgrade was to install a 360 degree bearing. To clarify what I said about the M20 bearing set, refer to Turner Motorsport's page and read what it says:

Main Bearing Set - M20, M42, M50, M52, M44, M54, S50, S52, S54
Part #: 11211706847 (11-21-1-706-847)
These are the "Yellow" main bearing shells for many BMW 4 and 6 cylinder engines. The size is 60.00mm. Set includes bearings for 6 cylinder cars. 4 cylinder cars get 2 spare bearing sets.

This item fits the following BMWs:
1990-1991 E30 BMW 318i 318is 318ic
1984-1991 E30 BMW 325e 325es 325i 325ic 325is 325ix
1992-1998 E36 BMW 318i 318is 318ti 318ic 323is 323ic 325i 325is 325ic 328i 328is 328ic M3
1999-2005 E46 BMW 323i 323ci 325i 325ci 325xi 328i 328ci 330i 330ci 330xi M3
1989-1990 E34 BMW 525i
1997-2003 E39 BMW 525i 528i 530i
2004-2005 E60 BMW 525i 530i
2000-2006 E53 BMW X5 3.0i
2004-2006 E83 BMW X3 2.5i X3 3.0i
1997-2002 Z3 BMW Z3 1.9 Z3 2.3 Z3 2.5i Z3 2.8 Z3 3.0i M Roadster M Coupe
2003-2006 E85 BMW Z4 2.5i Z4 3.0i - M54
2006-2008 E85 BMW Z4 M Roadster M Coupe
http://www.turnermotorsport.com/p-12919-main-bearing-set-m20-m42-m50-m52-m44-m54-s50-s52-s54.aspx

BUT, go to Pelican's website and for the same part number they have specific bearing kits for an M42 OR an M20:
http://www.pelicanparts.com/cgi-bin/ksearch/PEL_search_2014.cgi?SUPERCAT_FLAG=Y&make=BMW&Context_make=&please_wait=N&LastVisited_input=&Previous_Section=&forumid=&threadid=&command=DWsearch&make=BMW&description=11211706847&SearchButtonGo.x=15&SearchButtonGo.y=15

I hope that clears up what I said earlier.

E36m42 · « **Reply #12 on:** May 03, 2014, 07:24:21 AM »

Yeah I see what you guys are saying I might go with turnermotorsports bearings and what do you guys say about the pistons? Thanks for all the info guys!

thebrelon · « **Reply #13 on:** May 03, 2014, 02:31:57 PM »

stick with stock pistons if you want to boost later. you will just have to fit a thicker head gasket if you want to lower the compression ratio.
to decide if you have to fit new oversize pistons you first have to check cylinder bore: if they are too worn you'll have no choice but going oversize which means new pistons, otherwise and as long you don't want to increase displacement there is no reasons to fit new pistons.

E36m42 · « **Reply #14 on:** May 04, 2014, 06:26:29 PM »

thank you! Is there a build on here where someone went that route? with stock pistons and thicker head gasket engines and a turbo? how much boost can it handle that way?

Author Topic: Engine Building Advice (Read 7020 times)

E36m42

Engine Building Advice

thebrelon

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thebrelon

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E36m42

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thebrelon

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e3091318is

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e3091318is

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keflaman

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thebrelon

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thebrelon

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E36m42

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keflaman

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E36m42

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thebrelon

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E36m42

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