Thermostat installation. HELP!

[Chesty Bonds]

Hey guys,

I know i've done this thread before but i want to make absolutely certain i'm not taking on a job that's too big!

I need to install a new thermostat in my E30 318is. I've had a look and it seems like its going to be very difficult to remove the bottom two bolts that hold the thermostat housing at the front of the engine. Are you all understanding what i mean??

Do i have to remove the fan to get at the bolts, or can i just remove the cowling that covers it? Any other advice the BMW gods can offer? I really don't want to screw it up! I got a new Behr thermostat and gasket for $55.

Thanks.

 

[wood_e]

I'm not sure but I think a guy on the forum was in your situation earlier in the year, search the e30 forum for thermostat and you should find it. It's not that bad a job from what he said.

 

[Chesty Bonds]

Yeah thanks John. I checked out the old threads and there were heaps on replacing thermostats but they were all on the six-cyl versions! I've seen the thermostat casing on the sixes and it juts out quite prominently but on my 4-cyl (M42B18...or M40) its tucked away and there is hardly any space between the thermostat and the fan cowling and the fan itself. I'm not sure if i'll be able to get the spanner in and under to get the casing off!

Anybody know? All the replies come from blokes with the 6-cyl cars! [fake]

 

[jrt67ss350]

Hey there,

I've replaced the thermostat on my 325, and it was straightforward and easy just like you said. I looked in my Bentley, and according to it, it looks like the thermostat housing on the 4-cylinders is located inline with the radiator hoses. The picture it has shows the thermostat housing but is not very helpful. Here's what it says: "On 4-cylinder engines, loosen the three hose clamps on the thermostat housing and separate the upper and lower hoses from the housing. Pull the housing from the remaining hose. Installation is the reverse of removal."

It sounds to me like it is just a matter of disconnecting three hose clamps and pulling the housing from the hoses. From the picture, it basically looks like an aluminum junction block where three coolant hoses come together. Are you sure you are looking at the right thing? According to the Bentley, the thermostat isn't mounted to the engine.

 

[Chesty Bonds]

Thanks Justin,

Hmmm... i'm pretty sure i'm looking in the right place - effectively the casing that the two radiatior hoses are jubilee-clamped to. That's the thing, i definitely only have two hoses going through it from the rad so i'm not sure whats the deal here. The problem that i see as quite significant is the fact that there are four bolts holding the casing on to the block itself. These bolts are recessed and while the top two are easily removed, the bottom two are virtually concealed and their position is such that access to them will be inhibited by the fan and its cowling. Any more suggestions are, of course, welcome. This doesn't seem the easy job that i thought it was...

If you might have any other ideas i'd love to hear 'em. I never realised how many 6-cyl owners there were on this forum!!

 

[jrt67ss350]

If you might have any other ideas i'd love to hear 'em. I never realised how many 6-cyl owners there were on this forum!!

Six cylinder E30s seem to be much more common than the 4-bangers in the States.

Ok, the attached picture below is apparently the thermostat housing on your engine, right? Apparently, my Bentley is describing the thermostat housing on an older 4-cylinder. So, you are right on - you are going to have to remove the thermostat housing from the engine. Now, how do you do that - I have no clue - I have no personal experience working on the 4-cylinders. If you don't have enough clearance, I imagine you may have to take the fan off or something.

Sorry I couldn't be of more help.

 

[Chesty Bonds]

Yeah that's the housing alright. There are hardly any 4-bangers going around on this forum!

I think i might've bitten off more than i could chew... Thanks for the help mate.

 

[nadroj]

Its just you and me chesty

 

[Chesty Bonds]

LOL it is quite amazing! Yours going ok?

You done any work on your thermostat? I think i'm in a bit of a hole here.

 

[royalflush313]

You do not need to take the fan off. But you should take the cover off, it's only 2 little clips that hold them.
However, taking the fan off would make the job 100 times easier.

Pretty much all you gotta do is, drain the coolant, disconnect the 2 hoses, and take the 4 bolts (i believe they are 10mm if i remember correctly) off the housing, and you will be ready to replace your thermostat. Make sure you replace the gasket as well.

Once you are done, put it all back together, then bleed the system.

 

[Chesty Bonds]

Hey Hiro,

Yeah thats what i did the first time but i found that i couldnt get the thermostat to sit properly on the gasket with the fan on and so when i tightened up the casing it just ripped the gasket and the o-ring to pices and caused water to spill out down the front of the engine. When i did it this way the casing was very sloppy and hard to match up the bolts to the holes. I'm not sure it should be that difficult.

I think what needs to happen is to place the thermostat in the casing and put the whole thing in that way to ensure that it all sits correctly. To do this the fan is going to have to come off because it just doesn't give me enough room to move...

Unless anyone can give me a better idea? Cheers

 

[royalflush313]

i think you answered your own question. It's defenetely tight in there, if you need more room, just take the fan off.
I got mine in fine with the fan on, just with the cover off. It wasnt easy though.