overheating..head gasket?

[MKuser]

HI,
I´m noticing my mk3 ,2.5D,1991, Van, is overheating a little more than normal.I see some bubbles on cooling liquid but not foam in the expansion tank.
The cooling fan works fine.The radiator is a new one.
Can it be a problem in head gasket?
If it is ,can I change it myself?
If I let it go and the problem gets bigger,is it better repairing or trying to change the entire engine ?
Thanks a lot for helping

[Altransit]

These aren't noted for head gasket problems

Water pump failing

[MKuser]

I also notice that the air from the heating system, on driver´s seat,for example ,comes hot even on cold position ( the blue side).

If it´s the water pump,how can I check it'

thanks a lot for answerring

[MinorMatt]

The hot air from the heater is a seperate problem - hot coolant always circulates through the heater, the knob just controls how much air is drawn accross the heater matrix (full cold = no air across matrix, full hot = all air across matrix).

You can't really check the water pump, its a replacement job (and do the cambelt while you are there!)

[MKuser]

I'm getting overheating problem again...I've changed the water pump ,it's now 3 years,and everything ok but ,the other day ,I went up some mountain roads and the temperature went high,not on the red .After that,the temperature is always higher as normal and goes up when I take another inclinated road.Could I fix it with a reparation liquid in the coolant system?If I have to change the head gasket,does anybody know a tutorial to do it myself?Thanks.

[V184]

I'm getting overheating problem again...I've changed the water pump ,it's now 3 years,and everything ok but ,the other day ,I went up some mountain roads and the temperature went high,not on the red .After that,the temperature is always higher as normal and goes up when I take another inclinated road.Could I fix it with a reparation liquid in the coolant system?If I have to change the head gasket,does anybody know a tutorial to do it myself?Thanks.

try a thermostat, head gaskets don't normally fail

[MKuser]

Thanks,I´ll take a look...The reason I think it can be head gasket is ,after the overheating,the engine has lost force and,when I accelerate ,the coolant in the expansion tank makes foam...

[gotgcoalman]

head gasket is normally good for 250,000 miles or 400,000 km .
so it's not a regular thing

unless you've had major overheating issues.

do the radiator pipes become hard? (top rubber hose)
is there excessive pressure in the expansion tank?
did you recently drain the cooling system and re fill (could be an air lock)
how much water/coolant are you loosing?
how much white smoke when driving? (coolant in cylinders = lots)

[MKuser]

head gasket is normally good for 250,000 miles or 400,000 km .
so it's not a regular thing

unless you've had major overheating issues.

do the radiator pipes become hard? (top rubber hose)
is there excessive pressure in the expansion tank?
did you recently drain the cooling system and re fill (could be an air lock)
how much water/coolant are you loosing?
how much white smoke when driving? (coolant in cylinders = lots)

Well...I'm not loosing coolant,the hoses don't become too hard and there's some pressure in the expansion tank but not much...There's not white smoke

[karl]

edited i was on about mrk 7

[gotgcoalman]

It's reasonable to assume the head gasket is intact

For peace of mind you could get a coolant "sniff test" to totaly rule out combustion gasses in the coolant system.

as said it may be thermostat or another blockage in the cooling system.

Remove thermostat and see if it overheats under similar circumstances.

flush the cooling system while you're at it.

previous owner might have a some point added a "miricale cure" to the cooling system
and you're getting the backlash of it.

could also be a viscous fan problem (not cooling enough when under load)

[MKuser]

Thanks,everybody....I´ll make the test with the blue liquid to see if it turns green because of CO2 leak in coolant ...If not,I´ll try the thermostat ,the radiator( it´s been repaced new 3 years ago) or even the water pump ,also replaced...

[brickent]

Had the same problem before, and that's because thermostat went bad.

[Jim Archer]

Does it pressurise the cooling system quickly when cold? i.e. a minute or so rather than 5-10?

Jim

[axxez]

I had a heat-problem a while ago when my alternator went bad. After replacing it, I realized it was nearly stuck so causing a lot of load to the engine and therefore more heat than usual.
Not the first thing to search for, maybe not the 5th but after you have sorted everything else out maybe worth a look.