Over Heating Ford 1700 Crossflow

[My Seven]

Problem, my car has started to over heat after going over a

speed bump at 20 miles per hour. Under side of car not damaged.

My Caterham is a 1996 build with a 1700 Ford Crossflow Supersprint.

4 speed.

Milage: 2,700

The car has just started to over heat. Goes two blocks, temperature is in the red. There is a small hose off the left top side of the water pump going to a fitting that is blocked on the top of the Weber Carb manifold. Is this hose ever functional on this 1700 engine?

The car has no heater. The small hose may have been for a heater??

I drained & replaced the anti freeze with no difference in temperature readings.

Fan comes on if the sending unit is jumped. The thremastat does open when hot.

I jacked the front of the car up, Compression the radiator hose to check for an air trap. Does not help the over heating.

What reference sites address this problem? What is the model reference for this engine to purchase the valve cover gasket & water pump & blue hoses??

Any help would be greatly appreciated.

 

Thank you for your help.

Roberto

 

[Dave W]

Roberto

The first thing I would do is remove the thermostat and place it in a pan of water and slowly heat it up to see when or if it will open. If it is not a air lock, and it does not sound like it, then high probability that it is the thermostat. If you do get a new thermostat I would drill an 1/8" dia hole in it to help with filling the system and removing the air.

Dave W

[bsimon]

Goes two blocks, temperature is in the red.

 

No coolant circulation. a couple of things to look for.

 

1) air lock. Back side of stat is not seeing hot water and therefore does not ever open. This usually happens after a flush and fill. You might try drilling a 1-2mm hole in the thermostat's bulkhead to let coolant seep to back side. I haven't ever done this on a Kent block engine, but someone here might chime in on whether this would work or not.

 

2) duff stat. pull stat and check that it's actually opening in a pan of boiling water on kitchen stove.

 

3) water pump may have shot craps.

 

The fan won't start unless there's hot coolant reaching the bottom of the radiator where the switch is located. Besides, the car wouldn't overheat in two blocks with no fan.

 

>>must type faster, Looks like Dave beat me to it

[Ian7]

initial post says the thermostat opens when hot, so sadly sounds like the pump's sheared; no way to tell w/o pulling it off that I know of.

[escondidoron]

First things first. The original post says the temp gauge is reading hot. It doesn't say that coolant is boiling over or that there is loss of coolant. Also, 2 blocks distance is not sufficient time to overheat if the water is circulating unless the car has sat at idle for quite a few minutes time prior to driving. So….

 

A) Determine if the sytem is overheating or is the gauge faulty.

1) Is there any loss of coolant when the temp is high?

Are either or both of the radiator hoses hot when the temp gauge says high temp? If the hoses are not hot there is likely no coolant flow.

2) Check for coolant flow by removing the thermostat, and running the engine with the radiator cap removed. If there is flow the pump is likely good.

3) With the radiator cap removed examine the coolant. Are there bubbles in the coolant. If so it would indicate that there is a blown head gasket.

4) Remove the temp sender and place it in boiling (or as close to boiling as possible) water while powered up and connected to the car. Does the gauge read correctly?

 

If you have already done these basic checks then disregard.

[locost7018]

Dave Bean http://davebean.com/ is your friend for crossflow parts if you need them. Russ

[My Seven]

I removed the thermostat, replaced with a new gasket.

Started the engine, again over heated to the red zone

in 5 minutes. I will order a new water pump to replace the

present one. That sounds like the problem. Thanks

[My Seven]

Things I have checked, yet, still over heating.

1) Is there any loss of coolant when the temp is high? NO

Are either or both of the radiator hoses hot when the temp gauge says high temp? If the hoses are not hot there is likely no coolant flow. Hoses are hot.

2) Check for coolant flow by removing the thermostat, and running the engine with the radiator cap removed. If there is flow the pump is likely good. Flow is there with cap off.

3) With the radiator cap removed examine the coolant. Are there bubbles in the coolant. If so it would indicate that there is a blown head gasket. No Bubbles

4) Remove the temp sender and place it in boiling (or as close to boiling as possible) water while powered up and connected to the car. Does the gauge read correctly?

Have yet to do.

Other items???

There is an S.P.A. Oil Cooler in front of the radiator.

Should this be hot if the water radiator is hot? It is not hot.

The car came with an Accusump 2 quart Electric Pressure Accumulator with Moroso 23907 12-Volt Solenoid Pressure Valve Kit.

 

 

Thanks, Roberto

[Off Road SHO]

Two things needed to cool a water pumper engine: Water flow and coolant flow. Sounds like you have coolant flow. Does it have a clutch fan or ridgid mount? I replaced an entire engine and exhaust system on a Dodge 1 ton bucket truck trying to solve an overheating problem. Turned out to be a bad clutch in the radiator fan. That was an expensive lesson for me.

 

Tom

[timax]

Well , i'm putting my money on thermostat.

I had a very similar problem with a BMW once. Had flow but not enough.

The thermostat was not opening fully. I had the fan wires bridged to run them on full and still overheated.

Its the cheapest thing in the whole system to replace (unless its a BMW).

You say you havnt as yet run it without the thermostat in the housing?? Try this first before touching the water pump.

[BruceBowker]

Is there any reason a test can not be done with no thermostat at all?

[Marine7]

Roberto,

 

Others have mentioned the thermostat. I'd swap that to eliminate it from the equation. I'd then have to be suspicious of the gauge. You mentioned that the problem surfaced after hitting a bump. Perhaps the ground is poor on the gauge and causing it to give false readings. Could be the sending unit. Easy enough to check and or replace. After that, I'd have to go with a bad waterpump.

 

Good luck. Let us know what you find.

 

Jason

[pethier]

Was this ancient problem ever resolved?