Bleeding Water - C20XE Overheating

[ST-eater]

Hi, Today ive been trying to bleed the air out of the water system after fitting my C20XE. The project is ready to hit the road, but i have come across one final hurdle.

Im having problems with bleeding airlocks out of the system. The car gets hot, and NO FAN seems to kick in, (i have tested and the fan works off a switch, also upon testing the cables i have perm 12v to the fan, and the earth which is switched by the temp sensor in the rad all goes to where it should wire wise, but doesnt work... ive also replaced the sensor in the rad, yet it still doesnt work.)

Could anyone tell me when the fan should kick in, when looking at the temp guage?

I have flushed the rad out, and the engine block, and also reverse flushed everything. I have replaced the THERMOSTAT, TEMP SENDER AND TEMP SENSOR, and still no joy.

I can run the car on a normal fan switch, but it doesnt seem to do anything other than keep the temp from rising further.... although upon touching the rad, its cold as ice when the fans turned on.

Also on the interior of he car when i have the heaters on full, and at the hottest setting im getting cold air out of the middle two heater vents, and hot air out of the heater vents by the doors. So im not sure whats going on, and wether the middle ones work off a different part than the vents nearest the doors.

Water seems to boil up and air pockets come out, but its worrying knowing that the fan doesnt work, when the wiring says it should.. its as if the water isnt getting into the radiator....

The rad itself gets hot near the top, but im not sure if that is down to the exhaust or water...

Can anyone help ? Cheers

[AlexW]

I have a similar problem too

The centre dash vents Only blow out cold.

By what your saying i presume you disconnected the plug and bridged the 2 pins and the fan kicked in?

I cant help much more as ive got the same problem with mine

[dougie_boi]

middle heaters only ever blow cold mate if your systems air locked then your fan wont kick in because its not circulating properly and the water temp in the radiator wont be warm enough to trigger the switch for the fan your thermostat if standard gm one it should open when coolent in the engine is at about 87 degrees but same applies if air locked it wont circulate round the system to get air locks out just need to keep it ticking over and hold revs up a bit but need to keep a good eye on it and make sure it doesnt get to warm and roast the head gasket

[Lee]

The system should self bleed, ive NEVER had to bleed a water system on an XE when ive fitted one.

Are you sure you have plumbed it up right? You should have the pipe that goes around the back of the head with TWO small outlets on it, not THREE.

Header tank connects to one of these outlets.

The other connects to one side of the matrix (doesnt matter which). The other matrix pipe should connect to the side of the head.

There will also be a small water pipe from the cambelt end of the inlet manifold which would have gone to the second small inlet on the header tank of the original doner car. You need to T this piece into the single small pipe that runs from the top of the rad to the header.

If any of that is wrong on your car that could lead to massive air pockets in the system due to no circulation.

[General Baxter]

question

i take it you leave it on tick over to warm up
mines an x16xe, takes 10-15mins to reach half way on the gauge, then if i just leave it to tick over, it takes about 40mins for the fan to kick in
but the gauge stays at 1/2 way


its very hard to ask, when does yours kick in, there allover the place, 1/4 1/2 3/4

[General Baxter]

The system should self bleed, ive NEVER had to bleed a water system on an XE when ive fitted one.

correct, let it warm up with the cap off, once the thermo opens, you will see the water go from in the tank, LET THE ENGINE COOL, then top up the tank again,

DONE

[gaznovalet]

you can get cooler running thermostats wich open up at 82 degrees instead of 92, fans normally kick in at around 100 , just a query wot radiator is being used with this conversion and have you checked its ok? and is this a coscast xe or gm one as overheating can be the start of head gasket failure, hope this aint the case on yours.. . any oil in water- headr tank?

[Guderian]

i encountered something similar on an 8v corsa b the other week. bled repeatedly and still air in system. Still not resolved it.

Assuming no oil in water/water in oil, Still suggest a 'sniff test' on the coolant reservoir to see if there's any exhaust gas bubbling thro the glycol. Only way to be sure it's not the head gskt weeping.

[ST-eater]

Ive flushed it and tried bleeding again and there is no oil or rust or anything in the water. (done it with water only this time as i wasnt sure it was going to work)... there is nothing in the water as this is clear as ever. Ive cheked the exhaust and there is NO smoke, even running without a cat.

I know its a long shot but could there be an issue if the rad was fitted upside down.. (im not sure if it is even possible to fit upside down, but im thinking that heat rises and the temp sensor thing in the rad is nearer the bottom where the rad seems cool).

Ive been trying to bleed it all day, so im under the impression that there may be a fault in the way the tubes are fitted... Il double check and bang a post up in the next 15...

[ST-eater]

Looking in the bay my pipework is connected as follows....

Main Pipe from header tank connects to a large plastic pipe thing around the side and rear of engine block. One pipe from this goes to the left of the cars heater matrix, and the other goes to the bottom right on the rad.

The thermostat housing is connected to the top left of the rad.

The smaller part of the header tank connects to a 3 way 'Y' piece. One of these connects to the top small connection on the rad, and the other i think connects to the inlet manifold cooling thing, and then to the top of the block somewhere :S

The right hand side of the matrix is connected to the engine block on the right hand side..