M42club.com - Home of the BMW E30/E36 318i/iS

DISCUSSION => Engine + Driveline => Topic started by: MrPhatBob on February 03, 2017, 09:34:10 AM

Title: Thermostat housing fitment
Post by: MrPhatBob on February 03, 2017, 09:34:10 AM

I have a slight issue with my thermostat housing, the mounting point on the head:
(http://i.imgur.com/PIpnDql.jpg)
Seems to be missing a spigot ring because the seal on the housing sits in the middle of an empty space...
(http://i.imgur.com/JqCiPTW.jpg)
Have I missed something here, is the housing wrong for the head, or have I lost the ring, or something else stupid?

Title: Re: Thermostat housing fitment
Post by: 1998ccc on February 03, 2017, 10:47:13 AM

The plastic thermostat housings came on the M44.  Have you tried the Al M42 version??

Title: Re: Thermostat housing fitment
Post by: MrPhatBob on February 03, 2017, 11:54:23 AM

I'm not sure that I have one. This is a very late M42 engine from a 318ti which has a lot of the improvements that the M44 had, so... :(

Title: Re: Thermostat housing fitment
Post by: MrPhatBob on February 03, 2017, 12:03:27 PM

Yup, I should have one of these shouldn't I?
(http://img.photobucket.com/albums/v83/whitebred21/100_2083.jpg)

Title: Re: Thermostat housing fitment
Post by: 1998ccc on February 03, 2017, 12:12:07 PM

AFAIK the late M42's still used the aluminum thermostat housing but got the better head and timing bits.  I've read the late late m42's got the lighter M44 type rods.

Title: Re: Thermostat housing fitment
Post by: MrPhatBob on February 03, 2017, 12:45:04 PM

You're absolutely right on this, I had better look through my spares, and failing that - buy a new one!

Title: Re: Thermostat housing fitment
Post by: steel330i on February 05, 2017, 12:52:03 AM

Quote from: MrPhatBob on February 03, 2017, 12:45:04 PM

You're absolutely right on this, I had better look through my spares, and failing that - buy a new one!

I have a spare t-stat housing...let me know, $20 shipped

Title: Re: Thermostat housing fitment
Post by: DesktopDave on February 05, 2017, 10:10:54 AM

Aren't those housings directly interchangeable? That later 95deg thermostat always seemed a bit too hot for me; I'd replace it with the early 88deg unit. One more thing - the thermostat doesn't need a bleed hole with the alu housing, it's a small passage cast right into the housing.

Don't forget the o-ring and gasket. IIRC it's thermostat, then o-ring, then gasket, then housing. Be sure the bleed passage on the alu housing is clear. I've seen a few owners cut the paper gasket at that point so it doesn't clog the passage but I've never felt the need. I almost totally avoid RTV with these motors, but I'm quite fond of non-hardening gasket sealer/dressing (Hylomar Blue or M, Permatex #2, etc.). They help a bit with re-assembly and seem to prevent leaks down the road.