rebuild, cost/materials

new2bmw · 08-08-2010, 10:57 PM

I am just wondering, i dont want to do a full rebuild on either of my engines, cant afford it, but i have from now until spring to take one of them and do whatever i can do in my garage to freshen up one of the engines and to replace maintenance parts and if i find anything damaged. What is the least i should do on either my m10 or m20. i am not getting them ready for boost, just want to do whatever you would do if you cracked one open. also is there rebuild kits for an m10 and an m20. Thats most likely the easiest way, or at least it would give me a definitive list of what I need to buy.
cheers guys

JINT · 08-08-2010, 11:49 PM

I would get Piston Rings, Seals, Bearings, Gaskets and new valve rockers if they knock.

Dissembler · 08-09-2010, 12:05 AM

From top to bottom:

Throttle body gasket
Intake plenum gasket
Valve cover gasket
Valve seals (around the stems)
Rocker arms if you find any that look cracked
Camshaft bearings
Headgasket
Waterpump gasket
Piston ring set (includes compression rings and all 3 parts of the oil ring)
You shouldn't need wrist pins, but check em out anyways
Connection rod bearings (at crankshaft)
Crankshaft main bearings
Front main seal
Rear main seal
Front main seal for oil pump
Timing Belt plus tensioner
O-ring for the large crankcase tube
Oil pan gasket

Other things that are worth mentioning

Injector o-rings (or get them rebuilt)
Transmission input shaft seal
Spark plugs
Spark plug cap and rotor
Clutch disc, lightweight flywheel, pressure plate

All those parts plus machine work (planing head, boring/honing cylinders, cleaning crankshaft, resurfacing flywheel (if you use your old one)) will run you atleast 1000 if you buy the less expensive stuff, upwards of 1500-2000 if you use OEM.

IMHO, its not worth it on an M20 unless your building it for serious boost. As a former M10 owner, there never be a situation/possibility of it ever worth putting any money or effort into an M10 (especially the money part).

when you buy gaskets, I highly recommend victor reinz or OEM only. I've had very good experiences with victor reinz products, and their head gaskets usually have the valve seals packaged with them too.

If your gunna rebuild a motor, do it once, do everything. If your not willing to spend the coin, if ain't broke dont fix it. These old motors are bullet proof and dont really need a rebuild unless you have plans for power. Plus, m20s are dirt cheap and plentiful so, if it breaks, just swap it

new2bmw · 08-09-2010, 12:33 AM

so there is no doubt as a former m10 driver that i will miss anything about the m10 once i swap to an m20? I keep hearing m10 owners commenting on how nimble and quick the m10 is in the corners and that the extra weight of the m20 makes the car loose something. Any merit to those comments? I am also guessing that slapping a turbo on an m10 is not in your opinion the best option between that and an m20?
cheers

Dissembler · 08-09-2010, 12:47 AM

I don't miss it even a little bit. The power can only be described as pathetic, but credit where credit is due, I got better than 7L/100km.

You will not notice the extra weight in the corner unless your The Stig. Any cornering losses from putting a six in there are more than made up by the power advantage that the six has against any bmw 4 cylinder (m10, m42, m44)

I'm a noob on turbos, but many e30s are out there running 600hp on m20s, so boost shouldn't be an issue.

FWIW, when my M10 started suffering from electrical issues (im pretty sure it was just the alternator though lol), I used it as the perfect excuse to slap an m52 in there (like you, a turbo is in its future). You may want to consider that route as well (any M/S5X motor) as you sound like a person who could tackle a swap if you feel confident enough to pull and rebuild a motor.

Ceeker · 08-09-2010, 07:54 AM

Considering your first comment about affordability; there is no point in entertaining the thought of "rebuilding" an engine unless you are prepared to spend a considerable amount of money - tells me you are already aware of the cost associated to this. Labor is free if you have the time; parts are not..
Get an engine stand -preferable- and buy a gasket set. this will "freshin" up the engine's appearance. Otherwise if you start replacing stuff the $$$$ adds up very quickly. You'll be looking to spend 100-200 for an engine stand and 100-200 gaskets and a few bucks for paint and cleaning supplies.

DYMO · 08-09-2010, 08:43 AM

Quote:

Originally Posted by new2bmw

so there is no doubt as a former m10 driver that i will miss anything about the m10 once i swap to an m20? I keep hearing m10 owners commenting on how nimble and quick the m10 is in the corners and that the extra weight of the m20 makes the car loose something. Any merit to those comments? I am also guessing that slapping a turbo on an m10 is not in your opinion the best option between that and an m20?
cheers

my M10 was neither quick nor nimble. there's a S52 in its place now.

... then again it was a carb'd m10 1.6 instead of the usual m10

Bullet Ride · 08-09-2010, 09:45 AM

Quote:

Originally Posted by Dissembler

when you buy gaskets, I highly recommend victor reinz or OEM only. I've had very good experiences with victor reinz products, and their head gaskets usually have the valve seals packaged with them too.

From what I've read on e30tech

If you doing a proper motor rebuild (i.e. resurfacing head and block) a VR gasket will be ok. However for any inservice repair go with either Goetz or OEM as the VR gaskets have been known to start leaking within a year of installation.