Cross check on renewal items - M42

[BlackBMWs]

Getting ready to work on my Wife's 95 M42. Haven't had any coffee yet, so I figured I'd check in here to see if there's anything else logical to renew while I am replacing the Oil Filter Housing gasket and O rings. The chassis has 380k or so miles on it. No idea on the mileage on the motor.

I'm thinking:

• Oil Filter Housing gasket and O rings
• Cooling distribution pipe and O ring
• Water pump (see a little seepage of coolant)
• Main Serpentine belt
• Oil and Oil Filter
• BMW 50/50 coolant

I happen to have new spares and fluids on hand.

Anything else in the area? I hate to pull it apart and miss something right there to renew. ( Labor more expensive than parts.)

Thanks!

[spidertri]

Are you taking the intake manifold off to get to the coolant pipe? Do you have new intake manifold gaskets? New fuel injector orings? Coolant temp sensors that go in the head?

[LouM...]

Not to hi-jack but is there one of those cooling distribution pipes that fails more than the other? Or are they both eventually going to fail so replacing them both is the better approach.
Looks like one is easier to replace than the other.

LouM...

[BlackBMWs]

Originally Posted by spidertri

Are you taking the intake manifold off to get to the coolant pipe? Do you have new intake manifold gaskets? New fuel injector orings? Coolant temp sensors that go in the head?

Yes, from doing it previously, it is more effort to take apart, but easier and faster for access. I have upper and lower manifold gaskets.

I have a new coolant sensor for the head somewhere...

Thanks Dave!

Originally Posted by LouM...

Not to hi-jack but is there one of those cooling distribution pipes that fails more than the other? Or are they both eventually going to fail so replacing them both is the better approach.
Looks like one is easier to replace than the other.

LouM...

Hi Lou, on the M42 there is only one pipe. It does get brittle, so I keep spares on hand to replace it if it hasn't been replaced as a preventive measure since I'm in there anyway. Cirrus22 wrote in another thread a comparison between OE and OEM pipes as far as quality and straightness. I use the OE pipes.

[BRADESTAR]

I thought you could do the oil filter housing gasket without removing intake.

I think the belts and yer good. Maybe do the cooling later when starter or something else calls for it too.

[zoner]

LouM, the smaller elbow behind the head (M44 only) is more prone to failure than the larger elbow under the intake (M42; M44) but a failure is a failure and either can cause catastrophic damage so it's always a good idea to replace this before it goes bad or if you don't know the age of the existing. ALWAYS use OEM parts for critical applications such as this.

Rich, the only other thing I would check while you're in there in is the belt tensioner- on the M42, this is a hydraulic unit (as opposed to spring-loaded on later M44's)near the alternator (looks lke a miniature suspension shock) and can occasionally seize, causing belt slippage and/or squealing. Try to put a load on it- if it will compress and release, it's good. If not, it's a good time to replace.

[BlackBMWs]

Cool. Now that I am done with my other honey-doos, I can get to this set. I did find a new coolant sensor for the head and a new set of belts. Just came back from powerwashing the underside and will get on it now.

Bradstar, pulling the intake just makes it easier to replace the coolant distribution pipe. Getting to all the clamps is the issue. Not as limber to get to all the fittings with my too big hands.

[BlackBMWs]

Replaced the oil housing gasket and O-ring and the coolant pipe. I figure the pipe was a problem waiting to happen. I suspect the pipe had been swapped out at some time as the retaining bolts looked newer than the surrounding bolts. Also the O-ring on the Oil Filter Housing was solid and hard. It broke in two when I pried it out. (Lower right)



Cleaned up a bunch of sludge from the Oil Filter housing leak. I also cleaned the injectors while I had them out. Actually added some responsiveness according to my butt meter on the test drive. I didn't get to the water pump, but will do so at a different time. I can get replacement Water Pump bolts as I suspect they will be deteriorated

I did not replace the Fuel injector O rings. RealOEM lists two sizes. Top and bottom? I left the injectors on the rail, so I just needed the bottom O-rings. I reused the original ones, coated with dielectric grease. Will order the top and bottom as a renewal set if that's what's required.

In retrospect, I should have cleaned the ICV while I had it out. Not having issues, but heck, it was right there...

LouM, the M44 as Jerry mentioned has two plastic pipes. the Y connector and the coolant junction on the intake side of the block.


The one in the rear of the M44 head seems to be the fatal one. I have a set ready to go into my 98 M44, although, I know both pipes were replaced three years ago along with the cooling system when the motor was rebuilt due to the Y connector breaking. When I have to do the Valve Cover gasket, I will do the Y connector at the same time. The M42 only has the intake side coolant pipe. BTW, if you order the OE pipes, do remember to order the O ring too. They are separate items.

Easy job, just started too late to get all I wanted done.

Thanks for the help guys!

[LouM...]

Kind of frightening to see that picture your old coolant pipe. But definitely a good prompt to me to do them both.
Thanks.
LouM...