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 lol

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 lol

[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 lol

[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 lol

[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..

[ST-eater]

The only part of mine that seems like it could be possibly wrong is that my water pipe off the small 'Y' piece goes to the inlet manifold, then from there to the part on the left hand side of the engine, rather than going straight there.

[craig green]

I have parked mine on a hill (fr end up) to bleed it before. Air Bubbles rise.
But that didnt really help any more tbh.

Maybe someone has a good eng bay pic or coolant flow diagram for an XE?
User The Simps did a guide on the pipes necessary for the conversion, maybe searching his posts might shed some light...

[Lee]

The only part of mine that seems like it could be possibly wrong is that my water pipe off the small 'Y' piece goes to the inlet manifold, then from there to the part on the left hand side of the engine, rather than going straight there.

No, thats about right.

[ST-eater]

il have a look for the simps thing now lol... really doing my head in as i wanted to get her insured and on the road today :(

[craig green]

Maybe his thread on another site will help,

http://www.migweb.co.uk/forums/engines-transmission/307258-quick-xe-let-nova-water-hose-question.html

I'd be tempted to run it up to temp & occasionally manually switch on the fan to keep it from overheating. Should help with air lock issue & maybe with some uniform heat accross the rad/coolant circuit the fan will work OK.

[ST-eater]

Cheers, just looked at the migweb link and mine is similar to the way the pipework is, although there is no mention of the pipe that connects between the top rear of the block and then to the cooling part on the inlet manifold then to the header 'Y'. Maybe i have a blockage on this section... might get the pressure washer out again tomorrow and try blowing it through there, but im sure thats all fine anyhow...

So does the pipework connect straight from the header 'y' without passing through the inlet?

[craig green]

Being 'anti big block' I couldnt tell you. But if the wrong pipe is redundant or its flowing wrongly I guess the flow may backup & not circulate. Try finding some pics in project threads or galleries.
Sorry

[ST-eater]

Ive just blown through them tubes and water is flowing through. Seems to be correct, but will have a search through pics online and see whats what, :S

[gaznovalet]

wen car is running does water circulate the whole system ? can tell by removing header tank cap and see if any water is coming back thruw the thin top water pipe and into the tank?

[ST-eater]

Doing some searching and im bringing up that there could be problems with the heater matrix being blocked, and also there could be an issue with the thermostat.
I bought mine from halfords, and it doesnt have a bleed screw on it like some aparently have. Does the GM vauxhall thermostats have bleed screws on?

[ST-eater]

wen car is running does water circulate the whole system ? can tell by removing header tank cap and see if any water is coming back thruw the thin top water pipe and into the tank?


I get water and occasional bubbles through the small pipe. Not sure if its pumping through all the time though

[gaznovalet]

no gm thermostats dont have bleed screw just the aftermarket ones do, bubbles are sure sign of air in the system, wen you rev the engine or squeeze bottom water pipe the water shud flow back into header tank via the return pipe on top constantly, just out of curiosity wot level is the water to in your header tank and wen its been running if you remove header tank cap is it pressurised?

[gaznovalet]

also you can bypass the heater matrix by simply joining the two water pipes together wich run into it to see if this is at fault.

[ST-eater]

Just tried it, it flows a fair bit when the car is revved etc.
The car gets hot and still no fan or heat from heaters :S

[ST-eater]

Only tried running te car with the water in the header and the cap off... so im not sure i it does pressurise or not...

[ST-eater]

can you swap the heater matrix pipes around? as the one on the left (the awkward one out of the two) has two kinks in the pipe, and i would like to rule this out as being a problem... although it still seems like the thermostat is being the problem... cant see why as its a brand new one from halfrauds

[gaznovalet]

yes you can swap the 2 pipes around as it dont matter wich way the water goes in or out the matrix. worth a try if you see kinks present as they certainly wont be helping.

[Benn]

I have a gm hosing and it does have the bleed screw.

Let the car warm up, take the cap off every so offen till all the air comes out. Then top all if/when needed. Only way i've ever done it.

[ad4m]

ive been told that the fan wont cut into until the cap is screwed on water gets hotter under temprature and XE are self bleeding

[ant_tay]

i knid of have this problem i have a digi dash and mine goes up 1 bluse section and 2 yellow and if it goes up to 3 yellow bits the fan kicks in but i also get only cold out of the middle vents

[The Simps]

the middle vents will always blow cold. Hot should come from the side vents and screen slots.

For the sake of a few quid either try another thermostat, preferably gen.

When you're turning your heater nob to hot is it definately moving the flap on the side of the matrix as they tend to break.

The length of hose that goes from head, to manifold to your y piece isn't really needed. Try putting a small bit of hose on the head outlet and a bolt in the other end to block it off. TB & carb boys run like this fine.

[novaa]

fan in my xe does not come in untill its nearly at the last white mark on the gauge. have you cut back the first pipe out of the heater

[General Baxter]

another question,

have you played around with the wires on the back of the ignition switch ?

[Benn]

ive been told that the fan wont cut into until the cap is screwed on water gets hotter under temprature and XE are self bleeding

Fan will come on when the water gets to the right temp, you dont need to have a header tank let alone a cap...

[pingu-turbo]

Im not familiour with the big block coolant system. So forgive me if im talking crap. Is your water pump ok? Is the impellor slipping on the spindle? It looks like the only thing left to check.

[novanum1]

I had the same problem with my c20NE, and that came back to be the rad, even after i flushed it out, is the centre off the rad cold but the side bits boiling when the engine is hot,??

I had to buy a new rad to solve it, now it runs like a dreamer,

[mayhem]

when youre bleeding the system, do you have the heater on? i aways put it on max heat and #3.

btw, how warm should it be before fan kicks in? when i wire my xe up to the tech1, water temp goes over 100 degrees. 2 blocks on the digi, and after a long time on iddle the fan comes on.

[w88rdy]

mines doing exactly the same with a brand new rad and fan switch, the only difference i have is the original astra header pipe (small one from inlet) has a bolt in and doesnt go back to the nova header. the water seems to be flowing through the nova header fine and all hoses are hot?

If i remove the wire to the fan switch and link it the fan runs fine.

[Jon_nova1]

2 blocks on the digi is fine

pressurised water boils at a higher temperature, around 100 is fine, try coolant too?

[w88rdy]

my digi dash hits the red and still nowt??

[Jon_nova1]

well thats not right lol

http://img.photobucket.com/albums/v14/lashednova/20plumbingguide.jpg

do as the image shows, the holes for the hoses are there for a reason! have you had a volt/resistance tester on the
fan?

I took the t-piece of an old cav, it actually fits between the heater matrix and cylinder head pipe

[w88rdy]

http://img.photobucket.com/albums/v14/lashednova/20plumbingguide.jpg


I took the t-piece of an old cav, it actually fits between the heater matrix and cylinder head pipe[/quote]

I need to do some plumbing and shopping then lol

So the pipe was between the heater matrix and cylinder head pipe on the cav?

[Jon_nova1]

yes, but most people just plumb it into the thin pipes, because its easier than finding a 3cmish to 1cmish t-piece, i just came across it by chance lol

can't remember exactly how i put it, but if your bothered finding one, pm me and i'll check for you:thumb:

[Benn]

I'd just T it in to the rad run off, much easier.