Help Heaters Blowing Cold Front & Rear...

[karcher man]

Hi, Yes i had cold air in both heaters before the matrix change, The booster pump appears to be working correctly. i did remove the pipes from the rear heater and loop it out of the system it is worth noting it was extremely difficult to blow through the rear matrix hence the reason for leaving it out of the system.

 

It did warm breifley, so took it for a spin 50mph on open roads, now its blowing cold again, the thermostat has also been removed but i read on another post this may affect the front heater circuit, so ive got a new one to put in tonight, im also going to check the radiator tonight to make sure its clear.

 

If the rad is clear I suppose this leaves either the water pump is faulty, or head gasket however there is no water in the oil, no oil in the water and there are no bubbles in the header tank. the prvious owner had the garage put k seal in the water to try to cure the leaking heater matrix, so maybe this has clogged up the system.

 

As the car is due a timing belt change anway, im going to put a new water pump on it. Ill report back with the findings, i guess with faults like this its just a process of eliminatation.

[chrispb123456]

Maybe the impellor has fell off the water pump, apparently you can see/feel the impellor through the opening where the thermostat is fitted.

[karcher man]

Hi, Yes i had cold air in both heaters before the matrix change, The booster pump appears to be working correctly. i did remove the pipes from the rear heater and loop it out of the system it is worth noting it was extremely difficult to blow through the rear matrix hence the reason for leaving it out of the system.

 

It did warm breifley, so took it for a spin 50mph on open roads, now its blowing cold again, the thermostat has also been removed but i read on another post this may affect the front heater circuit, so ive got a new one to put in tonight, im also going to check the radiator tonight to make sure its clear.

 

If the rad is clear I suppose this leaves either the water pump is faulty, or head gasket however there is no water in the oil, no oil in the water and there are no bubbles in the header tank. the prvious owner had the garage put k seal in the water to try to cure the leaking heater matrix, so maybe this has clogged up the system.

 

As the car is due a timing belt change anway, im going to put a new water pump on it. Ill report back with the findings, i guess with faults like this its just a process of eliminatation.

 

All sorted - fitted new stat, blew through rad to make sure it was clear, refiled with fresh coolant solution, slowly with engine running, left cap off and brought up to temperature. Heaters blowing warm (getting excited by this point) put rad cap on and drove to fill up with fuel, heater still nice and hot temp indication showing 90, filled up fuel tank and drove back, approx 7 miles on open county roads 70 mph ish. All now appears ok, temp ok and heater hot.

 

Original fault: heater cold, apparent overheating and erratic temp gauge.

 

Cause - Rear heater matrix partially blocked and stat u/s, air lock caused by poor circulation due to blocked rear heater.

 

Fix - Loop out rear heater on pipes under passanger side rear door, ensured main rad and pipework clear, fit new stat, refill with coolant solution.

 

Refilling the coolant: start engine and intoduce coolant slowly to correct level, leave cap off and run engine to normal temprature, fit cap. check coolant leve after a short test drive.

 

i hope this helps someone, sorry for hijacking the thread. it may help when trouble shooting any system to make a list of all the componets, and test each one logically ticking them off the ist, you will eventuall find the fault. Just stop and think about it lol.

 

Thanks for the advice too, its amazing what power an open forum gives, and knowledge is power!

 

cheers

 

Lee

[peter oconnell]

you fitted a new stat ....... what is this ? thank you

[SilverBeast]

Hi Peter,

 

stat is thermostat, but bearing in mind your problems on the other thread I believe yours will be blowing cold as the Heater Matrix/Readiator is probably leaking, that's why you get steam on your out of the vents as it is hot coolant being blown through the ventilation system instead of warming the air via the heater matrix radiator. This will also be why your coolant level is low and more than likely why your passenger footwell carpet is wet, as the heater matrix is in the dashboard in front of the passenger - does the carpet smell of coolant/antifreeze. You could top up your coolant while the engine is cold and see if it goes down again, the vents start steaming and your carpet gets wetter!

 

NOTE:- Be aware that passenger footwell carpet getting can also be due to block drains under the wipers, the rear wash wipe hose join coming apart as that is under the trim at the bottom of the passenger door, and the drain for the sunroof disconnecting in the roof lining, though I understand this usually leaves a streak down the front windscreen....

 

Good luck

 

Richard