Air lock somewhere

Post by **paul72** » Wed Nov 20, 2013 2:02 pm

Ive just changed my thermostat hoping it wud cure my heating problem but its still only luke warm so i take it i have a air lock an have tried everything . Does anyone know proper way to get air lock gone as im sure this is wats causing problems . Car does not overheat thou and radiator fan never cuts in even wen left for ages running. Help !!!!!

89 UKDM BA4 4WS (resto job!) · Post by **wurlycorner** » Wed Nov 20, 2013 2:20 pm

Is it the right thermostat? There are 2 sizes available. I worked on someone else's lude once, that had the same problem as you describe and the new thermostat was the wrong size. It should sit right on the end of the housing. If it slides down inside the bore, it's the wrong one and won't do anything, it runs the same as if you didn't have one fitted at all.

There's a pic somewhere, I'll have a search for it...

EDIT: here is the pic of correct size next to the one that's too small. Photobucket seems to be having a dump atm, but I'm sure they'll finish that shortly and the pic will magically re-appear...

Post by **paul72** » Wed Nov 20, 2013 2:30 pm

Yeah got right one fits perfect but the bottom hose is not warming up

Post by **Merlin** » Wed Nov 20, 2013 2:36 pm

Have you bled the coolant system properly? Water flows out of the bleed nipple on the thermostat housing?

Post by **paul72** » Wed Nov 20, 2013 2:42 pm

Yeah i filled up radiator till it comes out bleed valve then put cap back on

BMCC · Post by **BMCC** » Wed Nov 20, 2013 3:58 pm

Did you open the bleed valve then pour in coolant till it is running out with no bubbles, might take a bit to do this if there is lots of air in the system. I always found having the car on ramps/stands helped get the air out as you are raising the level of the radiator. Also you need to let it run with the cap off for a good while as air will rise up to the top of the rad. Then let the coolant cool and add coolant as necessary before starting the car again. Run for a bit, let cool recheck level till your happy the system is full.

Post by **paul72** » Wed Nov 20, 2013 6:29 pm

Yeah i have tried that but it seems like bottom hose takes ages to warm up plus if there is a air lock in the inside heater how wud u get it out as one hose never gets hot but ive checked the valve an it opens as soon as u turn heater up

Post by **ADS1** » Wed Nov 20, 2013 7:16 pm

You may have to repeat the bleeding process a few more times to get any air out, it's worth trying anyway. Also, probably a bit of a long shot, but is there any chance some the smaller coolant/heater hoses have been dissconected at some point by previous owner, and refitted incorectly?? Just a shot in the dark, but worth checking.

Stevelar_granolar · Post by **Stevelar_granolar** » Wed Nov 20, 2013 7:39 pm

Did you whack the heaters on hot so it opens up the heater core?

Post by **paul72** » Wed Nov 20, 2013 7:52 pm

Yeah i have heater on full wack its been like this for a while its just now its winter u can freeze ur ass off in car thats why i thought its thermostat but not sure if pipes have been off before plus i even tried a rad flush incase of blockage