M42 maintenance list

[Dj Buttchug]

some of the pitting is also caused from electrolysis. It is more common on engines with aluminum heads. Custom made ground wires can really help with this issue.

[JoeyBones]

hmmm...uh oh...mine is loaded up with prestone premix... it said it was safe for all types...and the old was green too...

[Simon S]

The more I think about it - the more I'm sure it was the 'green coolant' that the PO used in my car - that caused the pitting.

Not 'poor casting'.
Jesus - even my thermostat housing was eaten up..

STAY AWAY FROM GREEN/PARTS STORE COOLANT !!
It will eat your aluminum components up.


edit: plus probable electrolysis as discussed below

[Simon S]

So nice when you finally figure something out.
As long as I’ve had my car – (storing and working on it mostly) I’d note drops of green-ish/blue-ish liquid on bottom of A/C compressor. I couldn’t tell if it was the compressor leaking some funky lubricant or what.

Before I put my head back on – I noted an ‘open’/no gasket area between block and front timing case.

So the bad casting issue I had with the case would cause coolant to slowly leak out from that open area – which is right fucking above the A/C compressor.

[Matt-B]

Nice Job Simon

[Simon S]

This post is in regard to my discoveries when addressing profile gasket surface on my m42 timing case. It involved the 'internal' coolant leak mentioned earlier. Honestly - it's a little weird - after seeing and addressing the issue - I really couldn’t see where this failure would/could cause long-term after effects. In other words, it's a coolant leak to a closed-off area in timing case that really doesn't seem harmful. Nevertheless, here are pictures of my discoveries.

Tore it down to the short block. Wanted to replace all gaskets.



What front of block looked like (note corrosion from "interior" coolant leak):



Back of timing case / how water pump was removed:



The timing case itself was a neat part. As I cleaned it - I was impressed with the amount of design and machine work it would take to manufacture.



Top of case



(failed) Relationship of case and profile gasket



Close up of poor casting



Tools used



Gooped up with JB weld



Shot of cylinder head at same connection point (ug! what's the deal here?)
(JB weld repair setting as I type this)



JB weld repair completed on timing case. New profile gasket test-fits perfectly in groove.



Hopefully - that should be the end of that..

[Nairb]

Here is my almost-complete list of things that I have replaced or added to my 1991 318is.. I did not add seals or gaskets to the list for the most part, because I just think that it's common knowledge to replace such things when doing work on a car. (For example, valve cover gasket when I had it powdercoated, etc)

With that said, depending on the maintenance history of your car.. these would be a good place to check up on to see if they need to be replaced.

Mods:
Mark D 93 Octane Chip
BBS RS 039/040 Staggered Wheels
M-Tech Illuminated Shifter
M-Tech 1 Steering Wheel
Front/Rear Strut Bars
Pioneer TS-D502P 5x1.25 Rear Speakers
Pioneer TS-A532P 5x1.25 Front Speakers
Pioneer TST15 3/4" Tweeters
Pioneer Premier DEH-P310UB Head Unit
Bilstein Sport Shocks (July 2010)
H&R Sport Springs (July 2010)
Diverse Motorsport 15mm Drop Hats (July 2010)
20% Charcool Lifetime Warranty Tint
K&N Air Filter
Euro License Plate
OEM BMW Mud Flaps
GG Interior Light Delay
Powdercoated Intake Manifold/Valve Cover
Deleted Power Steering (powersteeringdeletes.com)


Maintenance:
New Behr Radiator (April 2011) (145,000)
New Upper and Lower Radiator Hoses (April 2011) (145,000)
New Thermostat (April 2011) (145,000)
New Meyle Front Wheel Hubs (April 2011) (145,000)
New Powerflex Rear Subframe (February 2011) (144,000)
New Powerflex Rear Trailing Arm Bushing (February 2011) (144,000)
New Powerflex "Race" Differential Bushing (February 2011) (144,000)
New CV Boots (February 2011) (144,000)
New Bosch O2 Sensor (February 2011) (144,000)
New Pinion Seal (February 2011) (144,000)
New OEM Front/Rear Brake Lines (February 2011) (144,000)
New Rear Swaybar Links (February 2011) (144,000)
New OEM Steering Rack (September 2010) (142,500)
New Front/Rear Shock Mounts
New Odometer Gears (December 2010)
New OEM Hella Interior Light (August 2010)
New Fuel Filter (July 2010)
New Control Arms (July 2010)
New Tie-Rod Assembly (July 2010)
New Polyurethane Control Arm Bushings (July 2010)
New Front Sway Bar Links (July 2010)
New Timing Chain Tensioner (March 2010)
New Oil Filler Cap (March 2010)
New 4-Pintle Bosch Fuel Injectors [Part #:0 280 155 710] (September 2010)
New OEM Bosch Spark Plugs (September 2010)
New HQ Autosport Coil On Plug Kit (September 2010)
New Zimmermann Front/Rear Cross-Drilled/Slotted Rotors (July 2010)
Fixed the "Mess Under The Intake" (September 2010)
Royal Purple Differential Fluid (July 2010)
Crack Free Dash (December 2010)

[Dj Buttchug]

basically if you wanna rock m42 just know that you gotta put some time and effort into it to make them right. Just like any other production engine, the m42 has flaws. Consider the fact that most the engines had by us are well over 150k miles. With that kinda of mileage expect leaks/ worn timing components.

[Simon S]

To be honest - I haven't installed them yet.

In theory - any gains will be negligible/marginal. Most guys putting them in are usually doing other mods or maintenance of some sort at the same time. If you’re looking for specific documented differences resulting from swapping in just these injectors – I doubt you will find it. If you were to find it – it would most likely be on m42club – which is a place you should check out anyway. (m42club is where I found that pn – and learned about Motor Man)

If I were to guess – they’d be worth like +1/4 hp and maybe + 1-2 mpg. Again, pretty marginal. Think of it this way – they are the exact same injector – with a slightly more-optimal design. If your current injectors were partially clogged or unbalanced…

I am an optimization freak. I’m completely fine with negligible/marginal gains. I partially justify swapping these in under a ‘preventative maintenance’ category.

Anyone telling you you’re gonna get 5+ hp and 6 more mpg by swapping in ANY injectors on a stock-spec engine is bull shitting you.

[aworthybrother]

Dude - read post #22 of this very thread.

Yeah, found it. It was a very informative post. Thanks.

Bosch MPI injectors 0280150556. How long have you been using these injectors? Any gains (idle, mileage or performance wise)? Thanks.

[Simon S]

Dude - read post #22 of this very thread.

[aworthybrother]

Rob, or anybody - would you know which specific mustang injectors is required for m42? or do you know a place or link and part numbers to place an order? I want to replace mine with mustang injectors but doing a search is confusing me.

[Ryann]

that's like defending the old Chevy 350 diesel motor

No offense man. But it's NOTHING like defending the good-for-50k 350 diesel.

I have to admit that as much as I like it, it really does have more semi-serious flaws than it should.

[trackjunkie21]

i wouldnt call the m42 self destructive, ive beat on mine now for over 100k miles and it still wont die. Chain has had the 3k rpm death rattle for around 15k or so now, and at well over 200k on stock everything internal, it runs damn good. Maybe a few flawed designes, but definitly not self destructive. Bullet proof imo.

Just because yours hasn't, doesn't mean you can generalize and say it's a very reliable engine. that's like defending the old Chevy 350 diesel motor, or the vega motor.

[xwill112x]

i wouldnt call the m42 self destructive, ive beat on mine now for over 100k miles and it still wont die. Chain has had the 3k rpm death rattle for around 15k or so now, and at well over 200k on stock everything internal, it runs damn good. Maybe a few flawed designes, but definitly not self destructive. Bullet proof imo.