Help - Caterham Running Hot

Help - Caterham Running Hot

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jboult

Original Poster:

43 posts

262 months

Tuesday 15th July 2003
quotequote all
I have an old ('88) 1600 X-Flow Caterham which is running hot.

I've changed the radiator (needed doing anyway as the old one was leaking), and tested the fan (even bypassed the switch to leave it running constantly). However, the temperature gauge is still heading straight in to the red as soon as I get stuck in traffic, and once it's up there it seems very difficult to get it to cool down.

I'm due to take it to the track soon, and while I'm not worried too much about it heating up on the track, getting there could be a real problem... Any ideas anyone?

Thanks in advance!

Cheers/John

peetbee

1,036 posts

262 months

Tuesday 15th July 2003
quotequote all
Could be a stuck thermostat, try removing it and see what it runs like. If that cures it, either leave it out (in this weather shouldn't matter) or pop down halfords!

jboult

Original Poster:

43 posts

262 months

Tuesday 15th July 2003
quotequote all
Pete,

Not sure what you mean by 'stuck thermostat'. As a test I've already bypassed the thermostat switch so that the fan runs constantly, but it still overheats when sat in traffic.

Was this what you meant?

Cheers/John

Mark B

1,636 posts

272 months

Tuesday 15th July 2003
quotequote all
Pete means the thermostat that opens up the water way out of the engine in to the radiatro/heater circuit...

At the front of the engine on the nearside there is an aluminium housing which the top hose to the radiator exits from. There are three 13mm bolts holding it. Undo these, you will find the thermostat in there. If it looks proper filthy then it is likely to be very old. The thermostat is a heat sensitive openning which allows the warmed water in the engine to flow to the radator.

Take this out and replace the housing ensuring a good seal. Go for a quick spin in the car and see what the temp gauge reads. If it is cured get yourself to Halfords as suggested and get a new one for a 1980 1600 Ford Escort.

Hope this helps,
Mark.

PS - I never ran a thermostat in my old 1700 Sylva Striker Striker.

Mark B

1,636 posts

272 months

Tuesday 15th July 2003
quotequote all
Oh, and don't take it anywhere near a circuit until it is fixed or you may be looking at an expensive bill for new rings/liners if it cooks itself.



Graham.J

5,420 posts

266 months

Tuesday 15th July 2003
quotequote all
Mark, interesting, I've got the same problem with my 1600 X-Flow, constantly running hot. I will bear that in mind, thanks!!

John - If the timing is out it'll run hot, could be worth checking that.

Graham

peetbee

1,036 posts

262 months

Tuesday 15th July 2003
quotequote all
That was what I meant Mark
I've run cars quite happily all year round without a thermostat fitted, although in winter it took ages to warm up enough for the heater to become effective. Not really an issue in a Caterham tho!
Happy to help for a change, let us know if it worked.
Pete

grahambell

2,718 posts

282 months

Tuesday 15th July 2003
quotequote all
Although they're not expensive to replace, you can check if your existing thermostat is working or not before shelling out the readies.

How? Easy. Remove thermostat from housing and wash off under tap. As you'll see, it'll be closed. Then you need to tie a bit of string to a suitable bit of it and dangle it in a pan of water which you then heat up to near boiling point on your/your mum's cooker. Once the water's up to temp, pull the thermostat out and have a look to see if it's open or not. If it is then it's OK, if not it's knackered.

If thermostat looks OK, another possibility could be a mis-matched gauge and sender unit. Presumably you've got a Smiths type gauge. If you're using a standard Ford rather than Smiths (or whatever) sender unit you could get an inaccurate reading.

jboult

Original Poster:

43 posts

262 months

Tuesday 15th July 2003
quotequote all
Thanks all! As usual I posted without engaging brain and once I did I felt pretty dumb...

I'll let you know how I get on.

Cheers/John

jboult

Original Poster:

43 posts

262 months

Tuesday 15th July 2003
quotequote all
OK, an update...

Thermostat is fine - opens and closes nicely.

Fan was connected wrong way round, though (at least I assume it was - rear mounted fan blowing air back though the rad...). Tell me if I'm wrong!

Hopefully having changed the fan around things will improve.

I also think that there may be an air lock in the heater matrix, but I'm not sure what the best way to bleed it is (it is set high compared to everything else). Any suggestions, anyone?

Cheers/John

chrisx666

808 posts

268 months

Tuesday 15th July 2003
quotequote all
If changing the fan direction does not help, and you are concerned about the heater, try bypassing it with a short bit of heater hose and trying again.
Also check out the condition/colour of the spark plugs to see if the mixture and timing is OK. If your distributor has vacuum advance (or mechanical centrifugal for that matter) check that it is not stuck in the 'advanced' position.
I seem to remember ending up fitting a new water pump to my 1600 Mk1 Escort to cure a cooling fault - I think it only cost a tenner or something. Pretty easy job if I remember.

Chris.

Graham.J

5,420 posts

266 months

Tuesday 15th July 2003
quotequote all
Rear mounted fan (on engine side) should suck the air through the radiator rather than blow it at it as it'll be competing with the natural air flow.

grahambell

2,718 posts

282 months

Wednesday 16th July 2003
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One way to try to avoid air locks in high set heaters is to fill the system through the heater. Best way with X-Flow would be to disconnect heater hose from inlet manifold, insert funnel into end of hose and fill through that. Or you could try jacking front end of car up high as possible, disconnecting heater hose from water pump and filling through that.

Once water starts coming out through hose connection, reconnect hose, top up rad right to top and give it a run. Hopefully should give you completely full system.

jboult

Original Poster:

43 posts

262 months

Saturday 19th July 2003
quotequote all
Thanks to all for the answers - update so far:

1. Fan connected wrong way round - reversed and now works
2. Air lock in heater matrix removed.

Car is running much cooler - however it has developed a habit of tripping the fan fuse. Anybody have any ideas why it would be doing this?