temp guage problems...

[bongomaan]

hi,my van has always seemed to run quite hot however it seems to be getting hotter so, i have replaced thermostat and temp sender, flushed rad and system and bled v carefully .all air out,bottom hose nice and hot yet still guage shoots up, though i have noticed when i stopped and let it cool down bit ,when restarting guage @ 12 o clock but as soon as engine started shoots up to hot.have searched and the only possibility i can see is earth strap and will replace tomorrow but need to take bongochildren on hols on sat and any thoughts would be apreciated....btw last month she flew through mot with obligardo bit of advice about streering rack leak and he had a go at one of me tyres....sour grapes it you ask me.....bring on the sun....

[jaylee]

Load of waffle on here... http://www.igmaynard.co.uk/bongo/forum/ ... =3&t=48847 But may give ideas??!!!!

[jaylee]

Is it a Mason modified temp gauge? If so!? Take a voltage meter & check the state of the alternator too.. That can affect a Mason gauge... (Apparently.)

[bongomaan]

mason fitted but i have not moddified it, my thoughts are with the gauge as i expected to see loads of gunk come out of the rad and system when flushed but there was nothing and the coolant that came out was still sort of blue with no sludge or sign of rust and the stat opens ok ( old one tested and ok) and to be honest i just dont think it is overhesting....ps alternator done last year but will check....thanks for the thoughts jay.....

[jaylee]

Yep, i got a fancy face plate on the actual gauge, but underneath (like yours) its just got a Mason fitted....
The Mason certainly saved my arse when the top hose went about 3 years ago, or i wouldn't have noticed, stopped & seen the steam under the drivers door!
I just got a portable temp reader now just to put some sort of temp figure with the gauge read out.. I don't overheat either!

Just little paranoid, like you do..


Some more reading for you... http://www.igmaynard.co.uk/bongo/forum/ ... ep#p498836

[missfixit70]

I'd want to be VERY sure there isn't an overheating issue. Are you positive it's bled ok? Are heaters blowing hot when up to temp? hoses not too presurised? coolant levels ok? Did you get it up to the point where the fans kick in? If so, did that bring the temp down? It's not unknown for a new stat to be duff (I know bottom hose gets hot, but it may not be opening up enough) Was it a genuine stat?. Have you got anything you can use to measure temp? top hose on the drivers side should be between 80-90 under normal running (stat should open @ 82-85c), up to 96c before the low speed fan kicks in.
I'm not trying to scaremonger, just want you to be sure. Be great if it's a simple leccy problem.

[bongomaan]

just off to do earth now gonna re-do old one and add one of my own,im sure its bled correctly,heaters working when up to temp,thermo tested before use,old one too that was ok,coolant level not moved i have searched this one to death and am sure everything is sound,after two miles or driving last night the guage was at hot,why did the stat not open straight away if it was that hot,and why when you stop does the temp gauge go to middle with ignition on but rocket up when started.thanks for all replies.....regards,,,neil...

[bongomaan]

new earth fitted,old one cleaned,2miles on the flat fine soon as you show it a hill up it goes even when the stat opened and aircon on nothing will bring that needle down, my nose says its not cooking but sadly have now way to prove it so plan is to eat then go and bleed it again just incase stupid not to check again...too much to lose....

[jaylee]

Cheap peace of mind & you will have it by Saturday... http://cgi.ebay.co.uk/Digital-Infrared- ... c6ffaa6679 I don't work for em!!

[bongomaan]

mmmm.....not sure now, no air,still the same............

[Northern Bongolow]

how are you getting on with this ??.
things that may help.
is the new stat fitted a gen mazda one.? and is the jiggle pin still there.
is the water pump doing its job.
have you removed the inlet/outlet pipes from both heater matrix to establish if you have good flow through the primary circuit/heater circuit.
have you pressure tested the caps,if they are not holding pressure the system will boil earlier,and show more heat earlier.
if all the above is right then check the top port is clean in the top of the stat housing (engine side),if this is very dirty it stops the stat from closing the port off when temps rise.
to test the pressures in the system put a flat cap on the expansion tank and fit a pressure gauge to the vent pipe and start the engine. normal running pressures are warmed up, 5 pounds per s inch. very hot, fans about to come on is 12-13 pounds. if its hoter and therefore more pressure is being developed it could point to a head fault.
if all the above is ok then it may just be elecrical. or you have not bled it right, check the video's on youtube.
hope some of this helps.