Cooling probs again.

[shedrool83]

My temp slowly climbs even with the heater and fan on.

When i fitted the engine i fitted a new water pump and thermostat(80 degree) and used a s/h m535 e28 rad.

I have always had a problem when sitting motionless for any amount of time or in slow moving traffic.

I have always suspected the s/h rad to be at fault so fitted a brand new e28 535 one today and mounted the 14" leccy fan directly to it.

After fitting the rad i started the car from cold with the heaters on full and it ran for about 15-20mins before the temp reached the 1/2 mark on the gauge.At this point i switched on the fan and it seemed to sit at the 1/2 way mark ok so i switched off the fan and the temp started to slowly rise.

The hoses were quite hard and i'm starting to think its maybe the head gasket, but i aint lossing coolant and there is no water spewing out the header tank over flow.

Also though about the fan being not up to the job.

Thoughts please as this is doing my head in and i'm starting to hate the thing.

[leeparkes]

I take it youve bled the system?

With a 80 stat the needle should sit just above the quarter mark

[shedrool83]

Yeah system bled.
The heater are roasting and so is the rad ,all seems to be circulating ok.
The needle sit at 1/4 when i'm moving no bother its just at low speeds and at a stand still its giving me grieve .

[leeparkes]

Sounds like something to do with the fan if its ok when moving

What 14" fan is it?

[shedrool83]

It was an ebay special.


http://cgi.ebay.co.uk/UNIVERSAL-14-RADI ... arParts_SM

[zaust]

Is the fan right up agaisnt the rad ? It needs tobe as close as poss.
And have you taken the front valance off just to see if it is air flow ?

[shedrool83]

The fan is mounted directly to the rad.
I know you have mentioned the front valance before Mark so i'll take it off and see if it makes a difference as im running out of ideas now and dreading doing the headgasket.

[zaust]

I found just removing the ac cover's was plenty. If your worried, a local garage will test for head gasket leaks in to the water system. What's the conditon of the coolant bottle cap like. If the seal has failed it can cause the system to constatly boil.

Also with the fan, Do you have a relay installed, and what amp's is it.

[leeparkes]

Also with the fan, Do you have a relay installed, and what amp's is it.

And is it blowing the right way?

[shedrool83]

Fan is blowing into the engine bay and mounted on the front of the rad.I Just have it wire to a switch on the dash with a 20amp in-line fuse atm.


Results of removing the front valance.
Started from cold with no heaters or fan on.

After 10mins temp gauge showing 1/4 turned on the leccy fan and temp
kept rising slowly and was at 3/4 after the car running for 20mins.I then switch the heaters on full blast which brought the temp down to half quite quickly,then rose slowly and sat halfway between the 1/2 and 3/4 mark constant for 10mins before i switched the engine off .



Poor car as it sits atm.To add to the woes the valance is rotten at the corners so will need to replace that and the front slam panel is pretty rusty to.

[zaust]

Try a 30amp output realy with matching wire and fuse, the fan may not be blowing hard enough. I would also space the fan away from the rad but only by a centimeter, That way some of the air will dispurse side way's and hit some more of the rad. But apart from that it sound like your there.

Also where is your coolant bottle located ?

[shedrool83]

Coolant bottle is in the original position normally but i have it sitting on the suspension strut atm

[shedrool83]

Back at this again

Got a shot of a block tester and tried it today.

How i did it

Filled the tester with fluid and stuck it in the header tank.

Started the car and left it running until it got hot/thermostat opened at.(was getting bubbles in the tester while the car was running)

The block tester started filling at this point .

Removed the tester from the header tank and the tank was overflow.

Removed some water for the header tank and tried the block tester again this time pumping the bellow.

Again the tester stared to fill with coolant.

At no point did the fluid turn yellow .

Turned the engine off and removed the tester and the header tank was overflowing again.

I wish the fluid turned yellow and gave a positive test so i can say its deffo the head gasket.


Does the fact the header tank is overflow confirm the system is pressuring due to a faulty h/g?

Not sure the teater was working proper as when the fluid didnt change colour i tried it at the backbox and the fluid remained blue.


Help i'm getting no where fast with this heap o sh&t.

[leeparkes]

Throw that tester in the bin
Was the engine bled 'well'? ie front end in the air, coolant bottle uncliped and up high, engine held at 3k with the blowers on, etc...

Have you done a compression test, or the sniff test on it?

These are old fashioned engines and fairly bomb proof

[shedrool83]

Not done a compression test,but isnt a block tester the same as a sniffer test?

System has been well bleed,i was have had the car on a 150 mile run.It only got hot when in traffic but i never let it get above the 3/4 mark.

[durtyE30]

hi
sorry to hear you are having the same problem as me. my 1.8i is overheating when stationary or in traffic and is building up pressure till steam starts coming out the rad/header cap and bleed screw or it bursts a hose or water flange. the fan seems to be running very slow. it cools down as soon as i get out of traffic.

i don't think its the head gasket as there are none of the usual signs. its driving me crazy aswell. i got the car i wanted for years and its giving me constant crap.

anyone know of a good bmw mechanic in west midlands.

[leeparkes]

If it only gets hot when stationary id put my money on the fan not being strong enough.

If stationary does it still overheat if you hold the revs at say 2k?

[shedrool83]

Found this is the header tank tonight.

[shedrool83]

Found this is the header tank tonight.

Not tried that Lee

[Rav335uk]

Is that Oil on top???

[leeparkes]

[shedrool83]

Is that Oil on top???

Looks that way rav

Head off by the looks off it.

[shedrool83]

Should have the head gasket and bolt set by the end of the week then the fun begins.
Also bought an e34 aircon fan from a zoner so the fan size wont be an issue now either.

[Cypriotgeeza]

head gasket isnt really too bad to do tbh with you mate.. my main advice if your taking the head off with the inlet and exhaust manifolds still intact GET SOMEONE TO HELP as it is crazy heavy!

you need any help or anything pm me mate ill be happy to help!

P.S least it didnt look like what came out of mine:

[shedrool83]

Cheers. I have a hand so hopefully it will go smooth.

[Cypriotgeeza]

Hope all goes well mate..and i hope it fixes the problem your having!

[shedrool83]

Me too bud as i have about had me lot with it.

[leeparkes]

Any updates?

[shedrool83]

Picked up the gen gaskets set and bolts yesterday.
Dont think i'll be able to make a start until the weekend.

[shedrool83]

Did a quick test with the m30 air con fan .Car was running for around 15min and got to half way on the temp gauge before i put the fan on .The fan dropped the temp to just abit more than the width of the needle below half way.
Considering this was without the heaters on so i'm starting to think the fan wasnt upto the job.The hoses never got as hard as before either but taking it that will be because the temp wasnt as high.

I only have the fan wired to a switch via the battery with an in-line 20amp fuse atm and the wire was started to get rather hot so had to turn it off.

Still have the worry of the what looked liked oil in the header but if i can get the fan wired properly and the temp is staying down i think i'll run it for a while and see what happens.


There was a wiring drawing for the fan but i cant find it know,anyone got the link?

[Rav335uk]

Here you go mate.

http://www.aaroncake.net/rx-7/efaninstall.htm

[Brianmoooore]

Here you go mate.

http://www.aaroncake.net/rx-7/efaninstall.htm

Interesting article, but don't forget that an E30 has the fuse and relay already connected to the battery in the fusebox twice over (one intended for slow speed fan, and the other for full speed.) All that's required is to make up a loom from the fusebox to the fan and to the thermostat in the return tank of the radiator.
Much more interesting is the link http://www.aaroncake.net/rx-7/efanmyth.htm , which should be compulsory reading for everone thinking of fitting an electric fan!

[shedrool83]

Thanks Brian and Rav.

[shedrool83]

Next questions
Whats the thread size for the switch fan to fit into the side of a e28 535 rad and what relay will i use?Any other cars share the same switch?

Will any relay do or do i need on of a certain amp rating?

[leeparkes]

If it only gets hot when stationary id put my money on the fan not being strong enough.