e36 328 cooling

[andyiley]

Hi guys, I have a question for the masses of knowledge out there on PH.

I have an e36 328 track car & noticed the other day when I was out that it is now running a bit warmer than normal.

I have had it fitted with a 320 stat as that opens at 82 IIRC whereas the 328 one opens at 88, this normally means that on the road it runs at 2/5 of the temp gauge & on track will get up to 1/2.

I noticed the other day that it was at 1/2 on the road.

I do remember hearing that there are cooling issues with these engines, but not what they are specifically.

Can anyone assist me in this question, ie. What are the nominal issues & where should I be looking first?

Thanks guys.

[Dannbodge]

Normally the water pumps go and the radiator tops and bottoms bulge.

I would look at getting the pump changed and possibly a new rad and pipes.

All of which can be done for £150 (I got a very good quality pump for £35)

[andyiley]

Thanks for that Dan, I thought it might be the pump, but will check the rad & replace the stat as a matter of course.

The rad on my e39 530 was replaced due to bulging last year as a precaution.

[P924]

Viscous fan can fail as well.

[andyiley]

Thanks for that, another thing to check.

[andyiley]

Am I right in thinking that the issue with the pump is either plastic impellers that should be changed for metal or vice versa?

Just to help me get the right pump, if I need one.

[P924]

Exactly. you want the metal impellor.

You can test the viscous fan, by trying to stop it, while its running. use a rolled up newspaper pushed against the centre. If it stops easily it's toast.

[andyiley]

Thanks P, I did know of the newspaper test, just not what the weak points are of the system.

Thanks again, very much.

[iSore]

P924 said:

Exactly. you want the metal impellor.

You can test the viscous fan, by trying to stop it, while its running. use a rolled up newspaper pushed against the centre. If it stops easily it's toast.

That one again.

If it stops easily when the engine is at a normal running temp, it's fine. That's whole idea of a viscous fan - unless it's getting too hot, it's not really doing anything. They only engage when the engine is hot enough to require cooling. If a viscous coupling still looks clean front and back, it's probably okay. It's when they're black with dirt that they're in trouble - the oil leaks out past the seal and collects general road dust and dirt. If it looks old and shagged, it probably is.

[andyiley]

Thanks again, I didn't know about the visual side of that issue.

[P924]

iSore said:

That one again.

If it stops easily when the engine is at a normal running temp, it's fine. That's whole idea of a viscous fan - unless it's getting too hot, it's not really doing anything. They only engage when the engine is hot enough to require cooling. If a viscous coupling still looks clean front and back, it's probably okay. It's when they're black with dirt that they're in trouble - the oil leaks out past the seal and collects general road dust and dirt. If it looks old and shagged, it probably is

Thanks. Every day is a school day.

[carpetsoiler]

I've recently overhauled the cooling system on 2 328s.

In both cases, a Mishimoto M3 rad and M3 header tank were installed, along with EMP Stewart Components water pumps, metal stat housings and silicone pipes all round... plus viscous delete and a fan temp switch that kicks in sooner.

Both cars sit consistently at half on the temp gauge- if they go above half, your engine is dangerously close to being lunched. M52s do not like being overheated, and they like having their heads removed even less (threads come out the block).











It's quite an easy process- and strangely therapeutic. If you want any walkthroughs on how to do it, let me know. Just be aware that the system holds a mighty 10.5 litres of coolant, and it goes all over the floor/into drain pans/your shoes/your hands/your face/the next county.

[iSore]

Whilst that's all very well, there is nothing wrong with a standard 328i cooling system in good nick. The standard pump shifts enough coolant, the rad does its job, the fan cools it off when needed. These cars were designed to be driven hard and the standard cooling is more than up to the job.

I went to a 323i/328i launch event held at the Michelin facility near Almeria in 1995 - it was the same event where Michelin launched the first Pilot. We caned the t*ts off these cars up and down the mountainous circuit and oddly, none of them exploded in a cloud of steam.

I don't see any need for expensive upgrade stuff.

[4rephill]

iSore said:

Whilst that's all very well, there is nothing wrong with a standard 328i cooling system in good nick. The standard pump shifts enough coolant, the rad does its job, the fan cools it off when needed. These cars were designed to be driven hard and the standard cooling is more than up to the job.

I went to a 323i/328i launch event held at the Michelin facility near Almeria in 1995 - it was the same event where Michelin launched the first Pilot. We caned the t*ts off these cars up and down the mountainous circuit and oddly, none of them exploded in a cloud of steam.

I don't see any need for expensive upgrade stuff.

+1

The youngest E36 is now 14 years old and the oldest are 24 years old, and yet people talk about the cooling system as though it was fragile and prone to failure the minute the cars left the factory.

The cooling systems on these cars aren't really fragile, they're just old! - Were you to replace the entire cooling system with brand new OEM parts then the system would be fine for another 10 years+ .

[Olivera]

A friend and I are on our third E36 328i, and fourth engine in total! As others have stated the cooling system is marginal, and if overheated badly then it's usually new engine time.

[andyiley]

Update for you guys.

The stat has been changed & is fine, the viscous coupling has been checked & is fine, the rad has been checked & is fine, I have now recieved a new pump & that will be changed on Monday.

When this is complete I will be happy that all is as it should be going forward for the next many years.

I will update when this is completed.

Then, I will be doing the viscous fan delete mod (as it is a track car) and replaceing the (noe seized) A/C fan, ehich is probably the actual problem now I found it today.

[carpetsoiler]

iSore said:

I don't see any need for expensive upgrade stuff.

• shrug* suit yourself. I did it because...

- bigger radiator from M3 = better design, better airflow, far less likely to overheat.
- self-bleeding cooling system from the M3 a much improved design over the frankly st standard 328 one.
- metal stat housing- doesn't crack when you do up the bolts, compared to the st Bakelite one. I had leaks from the stat housing when it was original, and it was difficult to get a new Bakelite one to seal properly. So I went metal, and haven't had an issue since.
- the plastic impeller water pumps had a tendency to magically disintegrate into the block at around 100k. That's really not very useful. So I decided to get a proper part that will do the job well. Flowing more coolant is never a bad thing, is it? Also means I don't have to worry about pulling the pump out of the block every 50k to check it's in one piece.
- lower temp fan switch kicks the AC fan in sooner, thus allowing the car to stay cool when doing track work or being sat in traffic.

I'd rather have a future-proofed car that can take anything I chuck at it. It pushes out a lot more power than when it was standard, so it'd be nice to keep the cooling system up to scratch as well.