Overheating on track only

[maxmeerkat]

If your water temps are rising, have you considered the bmw motorsport thermostat ? Will be fitting mine soon.

[shimmy]

shimmy

My problem was faulty thermostat and fan coupling.

thank you please

Alex, remind me when your overheating happened (did it meet the criteria I pointed out above)

If your water temps are rising, have you considered the bmw motorsport thermostat ? Will be fitting mine soon.

Put in new stat then Motorsport stat. Does not make any difference to this as it is at hot conditions when any stat will be fully open

[maxmeerkat]

I guess next step is a race bonnet from Geoff Steele

[shimmy]

I guess next step is a race bonnet from Geoff Steele

maybe but not to cure this, it is something much more fundamental than that

[thegingerninja]

Sometimes when the internal coolant system reaches 7 or 8 years old there can be a thin layer of corrosion across the entire internal surface area. If the water temp reaches boiling point you can get "kettling" (small gas bubbles) forming on this line layer of corrosion. Obviously the air bubbles act as an insulator and the temp will increase if you don't drop the engine load.

I think there are some products you can run through the coolant system to remove the layer, and then refill using an additive which combats the kettling. I had a problem like this on a race car and I tried a product called water wetter - I wasn't convinced it would work, but I saw a drop in coolant temps afterwards, probably about 10 degrees.

I have spoken with some other csl owners who have experienced what you describe shimmy, particularly climbing the hill at the ring. We ruled out a failing viscous fan because of the sustained high speed would create plenty of air flow. The other possibilities were: radiator had lost it's heat capacity due to ageing, water pump lost efficiency or engine running lean (due to fuel supply not meeting demand at full throttle and high revs).

Only way to find out for sure is to rule them out one at a time.

[shimmy]

Sometimes when the internal coolant system reaches 7 or 8 years old there can be a thin layer of corrosion across the entire internal surface area. If the water temp reaches boiling point you can get "kettling" (small gas bubbles) forming on this line layer of corrosion. Obviously the air bubbles act as an insulator and the temp will increase if you don't drop the engine load.

I think there are some products you can run through the coolant system to remove the layer, and then refill using an additive which combats the kettling. I had a problem like this on a race car and I tried a product called water wetter - I wasn't convinced it would work, but I saw a drop in coolant temps afterwards, probably about 10 degrees.

I have spoken with some other csl owners who have experienced what you describe shimmy, particularly climbing the hill at the ring. We ruled out a failing viscous fan because of the sustained high speed would create plenty of air flow. The other possibilities were: radiator had lost it's heat capacity due to ageing, water pump lost efficiency or engine running lean (due to fuel supply not meeting demand at full throttle and high revs).

Only way to find out for sure is to rule them out one at a time.

great post, thanks

my oil and water coolant system is new as is engine. water rad i have not renewed yet but have cleaned and straightened fins.

water pump is new as is sensors and stats as well as wetter used.

def not fan as you say

my thoughts now are 100 cell cat affecting ecu at full throttle or fuel system running it just lean at full throttle

i have trief another fuel pump (no change) and now have just changed fuel regulator and filter. regulator does change fueling at full throttle so maybe that it, well soon see

[alexk]

Alex, remind me when your overheating happened (did it meet the criteria I pointed out above)

Well.
Very hot day, tight track, most corners with 2nd gear, oil temp at about 120C and then water temp almost reached red (it touched red).
I backed off a lot and it cooled down.

As you saw in my post for the thermostat tests, it was obvious that my stat didn't open fully so the water flow was not maximum.
I am not running any cats, just a backbox.
Might be a strange fact, but I doubt the engine runs lean when the consumption on track is > 26lt / 100km.

Shimmy.
I have a question for you.
Are you using the original BMW coolant fluid and is it mixed with water or not ?

[shimmy]

Well.
Very hot day, tight track, most corners with 2nd gear, oil temp at about 120C and then water temp almost reached red (it touched red).
I backed off a lot and it cooled down.

As you saw in my post for the thermostat tests, it was obvious that my stat didn't open fully so the water flow was not maximum.
I am not running any cats, just a backbox.
Might be a strange fact, but I doubt the engine runs lean when the consumption on track is > 26lt / 100km.

Shimmy.
I have a question for you.
Are you using the original BMW coolant fluid and is it mixed with water or not ?

i have whatever bmw put in with. new engine, not sure what

[O'Neill]

Wasn't your car remapped some time ago? has the ecu been put back to oem/maybe try another ecu if your new parts don't solve the problem.

Or oil cooler and mishimoto rad.

[northernjim]

Let's face it.... These csl's are just am expensive pike of junk really


Never had these problems with my blue oval running oodles of boost! :hahaha::hahaha:

[Mark CSL]

Let's face it.... These csl's are just am expensive pike of junk really


Never had these problems with my blue oval running oodles of boost! :hahaha::hahaha:

They dont run long enough to have overheating problems :whistle:

[alexk]

i have whatever bmw put in with. new engine, not sure what

The bottle says to mix it 1:1 with water.
It is better to have plain fluid though.

[shimmy]

They dont run long enough to have overheating problems :whistle:

And 100% throttle is about 35bhp :thumbs:

[CraigMillwardCroft]

Let's face it.... These csl's are just am expensive pike of junk really


Never had these problems with my blue oval running oodles of boost! :hahaha::hahaha:

Just lag out of the corners :whistle:

[northernjim]

Just lag out of the corners :whistle:

:whistle: :bigcry: it's the only reason I've gone rwd now...