Messages

1

Engine + Driveline / Help: Engine overheating and lots of bubbles in coolant...

« on: January 22, 2013, 03:43:10 PM »

Thanks Dave. Can you explain more about the coolant boil over? What do you mean if the system cant hold 30 PSI, it will boil over? Why wouldnt it be able to hold 30 PSI?

Can I purchase one of those testers at autozone that checks for exhaust gases in coolant?

I'm thinking you're right (but hoping you're wrong) about the cracked head.  I'd check all the other stuff first, to be sure.  

Like Dean says, it's possible that you're getting a boil-over in the system. The M42 operates at a higher coolant pressure than most cars.  If the system can't hold 30psi it'll boil over.  Another annoyance is that bleeding these cars is a PITA, especially with that mickey-mouse throttle pre-heater disaster under the intake manifold.  Also check for coolant at the plastic manifold on the driver's side of the block - they tend to crack & leak a bit as they age.  Don't take it off unless you have an OEM BMW spare as they always dissolve into at least three pieces.

Alternatively, can you get the exhaust gas tested for coolant when it's good and hot?  Or the coolant tested for combustion gases?

2

General Topics / Replacing engine: Different between '93 M42 and '95 M42

« on: January 21, 2013, 03:00:16 PM »

Great. Should I be able to just take the new engine, already connected with wiring harness from '95 m42 and ECU from M42 and just drop it into the '93 body? Really what I am trying to ask is, will the '95 Engine Harness connect to the '93 body without any sort of modification?

3

General Topics / Replacing engine: Different between '93 M42 and '95 M42

« on: January 21, 2013, 12:58:30 PM »

Hey guys,
   So I'm having some major issues with the cooling of my 1993 318is. I've done major head work and still having issues so thinking about just replacing the entire engine to save the headache.
 
          I found a M42 out of an early '95 318ti. Complete engine, tranny, harness and everything.  I ran the VIN and confirmed it is a M42. According to real OEM, the part number for the engine is 110 090 6 64 91 which is a little bit different than the part number that is showing up for my car 110 090 6 53 89 . Both car confirmed to be M42's.

      Question is:
       Does any one know the differences between these two motors? Can I drop the '95 318ti motor into my car fairly easily? Anything I need to change?

Thanks.

4

Engine + Driveline / Help: Engine overheating and lots of bubbles in coolant...

« on: January 21, 2013, 12:03:00 PM »

Hey all,
   Hoping you can throw some ideas at me for this issue. I have a 1993 BMW 318is.

   I purchased the car with the exact issue it has today, I originally diagnosed the car as having a bad head gasket, or cracked head. After removing head gasket, visual inspection looked good, so I assumed it was a cracked head since apparently this is pretty common. After taking the head to the machine shop and having it pressure tested, they said that it was NOT cracked. So knowing that, maybe it was a small leak in head gasket, so I had them rebuild the head while it was off.
   I put the rebuilt head back on with complete new head gasket kit and it is having the exact same issue as before. When the car is cold, I don't notice any real bubbles in the coolant but as soon as it warms up, there were violant bubbles coming through the coolant system.

   1)I am thinking that it is just a hairline crack in the head that seems to seal when cold but as it heats up the crack expands and opens up.
   2)Other thought, is that it may possible be a cracked block.
   3)Are there any other things that could cause this?

Thanks.