M42 maintenance list

[Simon S]

Not aware of specific threads – but from time to time, I’ll catch a thread where someone finds little plastic ‘chunks’ in the oil pan. These chucks are generally from old chain guides.

The updated guides and pressure valve are just that – updated parts from BMW. The guides become brittle with age and heat cycles. I’ve read that the plastic/nylon oil pressure valve replaces a metal version which can seize – although, I’ve never heard of one seizing – but it’s a cheap part to replace ‘while you’re in there’.

Here’s the injector part number I ordered from Motor Man Fuel Injection Supply (www.injectors4u.com)
Bosch MPI injectors 0280150556
– from what I understand, they’re practically identical with exception of 4-pintle rather than our 2-pintles (as stated – for better fuel atomization).

Sounds like our maintenance builds are pretty similar. I found crank and cam sensors to be pretty expensive – so I plan to run originals for now. (def a good idea for fresh O2 sensor though)

A ‘full top end gasket set’ as I understand it simply includes a new head gasket and new head bolts.

I’m not familiar with VW lifters mentioned – and am also skeptical that replacing your existing lifters is worthwhile.

Gaskets? Just get all of them. Seriously. m42s tend to leak like pigs. (oil pans, oil filter canister, upper/lower timing cases, and profile gaskets)

While some say m42s are time bombs – I believe performing preventative maintenance on them (profile gaskets, timing chain guides & tensioner, etc.) is worth it in the long run.

COP conversion is similar to running the 4-pintle injectors – mostly an optimization thing. COP conversions are popular on m42s because plug wires are removed from equation. In one example, Grassroots Motorsports discovered an astounding 6 hp increase after swapping in new plug wires on an e30/m42. Not because the wires were that great – but because the originals had become that worn. Also, the cost of new plug wires alone is comparable to finding a COP kit (plate, coils, and hardware) to install.

I’m excited to be running a COP/4-pintle injector/MarkD chip combo as well. Horsepower gains should be negligible – it’s the increased/optimized fuel economy that gets me excited.

Before jumping in – you may want to do some initial checking on your engine. Compression test will give a good indication of general health. Pulling the valve cover will let you see cam gears. (square teeth = good. Pointy teeth = bad)

Good idea – if you haven’t already – is to search around for a pdf version of Bentley’s e36 manual online. (m42 not covered in Bentley’s e30 manual)

Some are excited to keep m42s healthy – others (many) get turned off and start looking for m50/s5x swap options.

Good luck and have fun.

[5ickride]

Looks like you're going all out. I'd go ahead and get the full top end gasket set 'cause you'll need it if you're doing the profile gasket. And why not replace all the crankcase vent/vacuum/icv hoses while you're at it?

Any details on the "Top end gasket set"? Or a link?

I'm really trying to just develop a comprehensive list of all maintenance parts that should be replaced at some point or another. I'd say most of the things i've listed will get done but this all depends on how much this all comes out to be.

Thanks

[JoeyBones]

Ok, after reading this it appears Ive missed a few things along my way...are there any threads on the updated oil pressure relief valve and upper chain guide?

What part numbers for mustang injectors or from which year mustang? Are they plug and play?

Same for VW lifters...

[z31maniac]

And why not replace all the crankcase vent/vacuum/icv hoses while you're at it?

"Mess under the intake" takes care of all that.

[jintermont]

Mustang injectors are 4 pintle as opposed to ours which are 2 pintle. So they provide a better burn and atomize the fuel better.

[Ryann]

Looks like you're going all out. I'd go ahead and get the full top end gasket set 'cause you'll need it if you're doing the profile gasket. And why not replace all the crankcase vent/vacuum/icv hoses while you're at it?

[z31maniac]

Glad to see the oil pressure relief valve on here. It's just as likely a cluprit for chain rattle as the tensioner.

And it's a cheap part.

[5ickride]

Pull engine

Rebuild 2.1lt.

LOL

Seriously though it depends how far you want to go. A list of things I would recommend listed as high priority to low priority.

Change Fluids
Timing Chain Tensioner
Check oil pick up bolts
Mess under the intake
Delete Heater Plate.
Water Pump
Thermostat
Timing Components
Fan Clutch
COP Kit
Mustang Injectors
VW lifters

And if you are really keen and competent get a Head Gasket kit.

Thanks for that list! QQ, what are the "Mustang Injectors" for? Performance? Also, my ignition coils seem to be good ATM, but should I still see about getting a COP kit?. Finally, what are "VW Lifters?"

It may or may not need anything. How many miles on the ODO? Did it come with any service records? I say if it's without chain rattle, idles nice, and doesn't loose coolant just change the engine/trans/diff oil, fuel filter, and air filter and drive it.

She's got under 106k and no records besides what I was told. The Idle is bouncy when I start her up but then settles and idles fine once engine is warm.

I've put together a list of what I'm thinking about changing:
-Belts (AC, PS, Alt)
-Intake Manifold Gaskets
-Water Pump/T-Stat
-Valve Cover Gasket
-Timing Chain Tensioner
-Timing Chain Guides (plastic version)
-Lower Pan Gasket
-Profile Gasket
-Oil Pressure Relieve Valve
-Sensors (Crank Position, o2, Coolant, Camshaft Position)
-Hoses (water, coolant)
-Filters (oil, fuel, air)
-Spark Plugs
-Fan Clutch
-Fluids (oil, trans, diff)

I'll also:
-Delete Heater Plates
-Delete the useless coolant lines under the IM
-Clean out throttle body and ICV

Anything major that i'm missing?

Thanks

[Ryann]

It may or may not need anything. How many miles on the ODO? Did it come with any service records? I say if it's without chain rattle, idles nice, and doesn't loose coolant just change the engine/trans/diff oil, fuel filter, and air filter and drive it.

[Simon S]

^^ good list right there

[Massimo]

Pull engine

Rebuild 2.1lt.

LOL

Seriously though it depends how far you want to go. A list of things I would recommend listed as high priority to low priority.

Change Fluids
Timing Chain Tensioner
Check oil pick up bolts
Mess under the intake
Delete Heater Plate.
Water Pump
Thermostat
Timing Components
Fan Clutch
COP Kit
Mustang Injectors
VW lifters

And if you are really keen and competent get a Head Gasket kit.

[5ickride]

Thanks, I also just bought a MarkD chip to go along with the maintenance, hopefully she'll be a gem when she's done.

[MikeDE]

Check out m42club, site devoted to that rattly little bastard.

I lol'd, woke up my kids.

[Dj Buttchug]

valves are hydraulic. no adjustment is needed

[NightfoxCT]

Recommend checking out a few of your sensors also. Tps/ 02/ coolant

Clean out Trottle body and ICV

Valve adj.

and everything above