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Over Heating Crossflow
Blairm - 14/2/05 at 02:27 AM

Hi,

My Xflow 1600 does not seem to like to idle with out over heating. Originally I though I had some air locks, but think I am over this. I have removed the thermostat and things improved (I have tested and it was OK), but with Thermo fan running in mid 20 deg C air temperatures I can not get much past 10 minutes before it is over 100 deg C. It is a fresh motor which I was giving the initial few burst of 2500 rpm for 10 minutes or so when the issue arose. Short bursts around the road (avoiding the coppers at present) are not indicating the same problem.

Is it to much to expect the thermo fan to keep up for more than 10 minutes while stationary?

It has a new core and it came out of a ghia and seems to be a little larger than other escort units I have seen. Only just fits in the nose cone

Cheers Blair

[Edited on 14/2/05 by Blairm]


stevebubs - 14/2/05 at 04:11 AM

Key things to check are:

1) timing - too much advance or retard will cause overheating

2) airlocks


britishtrident - 14/2/05 at 07:59 AM

quote:
Originally posted by stevebubs
Key things to check are:

1) timing - too much advance or retard will cause overheating

2) airlocks


Yes sounds like it is too retatrded --- this causes more heat to be rejected to tyhe cooling system atlow crank speeds.


rusty nuts - 14/2/05 at 07:04 PM

As already mentioned timing , airlock possibly also weak mixture but unlikely. Is cooling fan wired/fitted to give airflow through the radiator from front to rear ? could explain why car overheats when stationary but not when moving . Are hoses in good condition and correctly installed i.e. top hose to top of rad and water pump inlet connected to bottom of rad ?. Is inlet manifold heater connection bunged up ? wants connecting to water pump stub possibly via heater H.T.H. Rusty


theconrodkid - 14/2/05 at 07:11 PM

sounds like circulation prob,is the water pimp impeller ok,stat opening and rad not blocked/getting hot on its entire surface?


Marcus - 14/2/05 at 08:15 PM

Could be the fan designed to be a sucker, polarity reversed so it blows. Aerodynamics of the blade means very poor efficiency if going the wrong way.

Marcus


Blairm - 15/2/05 at 02:17 AM

Thanks for all the replies

The gentlemen who helped me start it the first time checked the timing and from memory said it was 8 Deg. Is that OK?

The manifold is plumbed to the water pump which I replaced with a new unit when we put the motor back together.


How do I tell if the fan is a sucker or a pusher?

At present I have it on the front of the radiator and pushing air through (the girl in the shop could not tell me when I bought it if it was a pusher or puller) and I was not aware they acted differently. It has a blue and a black wire which did not give me any real clues as to it operation?

Cheers Blair

[Edited on 15/2/05 by Blairm]


stevebubs - 15/2/05 at 02:32 AM

IIRC the Mexico had a static timing of around 8 degrees. Xflows are typically between 8-12 depending on tune. Mine was at 8 degrees and exhibiting similar problems - I've a feeling that unleaded petrol wasn' t helping the fact.

May be worth advancing it a degree at a time until the problem goes away (if it hasn't gone away by 11 degrees then this isn't the problem)


stevebubs - 15/2/05 at 02:34 AM

quote:


How do I tell if the fan is a sucker or a pusher?



The safest way is the paper test.

Get an A4/letter sheet of normal paper and wait for the fan to come on.

Put the paper infront of the radiator. it should be sucked towards the back of the car onto the radiator. If not, then the air is being pushed the wrong way

Stephen


stevebubs - 15/2/05 at 02:37 AM

quote:
It has a blue and a black wire which did not give me any real clues as to it operation?




the black wire is typically connected to the earth - only *really* crucial if there's any metal bits on the fan (otherwise you would have an exposed +ive feed which could cause a short)