Club 80-90 Forums

hi all....sorry i know this one will bore ya (ive seen the lists of posts on overheating probs!!)but....
we have a 1984 -1.6 diesel .we have suffered over heating issues on journeys longer than around 5 miles ,but found that when we turn the heater on (it only works on position 2 but thats a problem i can fix!!) it doesnt overheat...fine for useage around town but sunny weather and say 25 miles with heater going full bore!! not gooood!
if anyone knows what my be causing this i would be greatful.

m&m smith+1 wrote:hi all....sorry i know this one will bore ya (ive seen the lists of posts on overheating probs!!)but....
we have a 1984 -1.6 diesel .we have suffered over heating issues on journeys longer than around 5 miles ,but found that when we turn the heater on (it only works on position 2 but thats a problem i can fix!!) it doesnt overheat...fine for useage around town but sunny weather and say 25 miles with heater going full bore!! not gooood!
if anyone knows what my be causing this i would be greatful.

have you checked the coolant level ?
start the engine with the top off the expansion tank(the one to the right of the engine)..with the heater on hot and see if it needs topping up(to the brim).keep the tank filled to the brim...you can do this till it reaches temp without the worry of pressure building up.give it a few revs to get it moving and after around 5 mins there 'should' be no more bubbles coming through.if the engine reaches temp and theres still bubbles coming through then it might be a bit more sinister
you could also try changing the thermostat as by the looks of it the heater matrix is acting as a second radiator for the engine.could just be air in the system though fingers x .
if all seems well put the top back on the tank and keep running a further 5 mins and see if theres any leaks under the van ...good luck

coolant lvl is fine and pumping round all ok,so will check thermostat and try a drain and refill case of air in system !

When my 1981 1.6 did that it was the head so I hope its not for yours. What appeared to be happening was air getting into the cooling system so it would gradually airlock. The only thing I could come up with with the cooling down with the heating running was that the small heating radiator was actually just enough to cool down the engine. Once I drove a few hundred km from North Kenya to Mombasa like that... the only thing was initially I could keep about 50 kph without overheating, but by the end it was down to 25 kph.

My suggestion is do exactly what you plan to do, see if there is any air in the water but if it comes back after the next five miles check to see if there is too much pressure in the expansion tank...if so you you could be looking at something more serious than that...

Dubwana

found leaks on rad and fan doesnt work!! small leak on main pipe also,new rad and fan coming pipe fixed ..shall fit bleed and update as i go thx all!!