another overheating topic

[poknat]

good day tsikooters!

I just bought this 91 volvo 460 automatic as a project car and i am having 2 issues to diy at the moment.first one is overheating, service history reveals that the previous owner brought the car to the dealer for repair due to overheating while at idle.they changed the thermostat,fan switch,and coolant.

That was 8 months ago and right now it's still overheating at idle.the temperature needle goes way up near the red line after 15 mins of idling.I drove the car on the motorway for 20 miles and the needle went up and remained on the same spot.This morning i checked for coolant leaks but there is none.No sign of oil on the expansion tank or coolant on the engine oil and no fluid loss.Hose appeared to be in good condition and no leaks on the connections.I let the engine idle for 20 minutes and the needle gradually went up just a fraction below the red line at that span of time.The top and bottom hose became hot and so as the whole surface
of the radiator and coolant on the expansion tank went up a bit.I turned the heater on and blows a very hot air but no smell of coolant.Top hose looks like water is going through when i squeezed it but i didn't felt any of the pulsating or vacuum pressure from the waterpump.

Now here is when I need your assistance and wisdom please.To start with I am not that much mechanically inclined but i want to diy the things before passing it on to the garage.My plan for the next few days will be flushing the radiator coz I'm not sure if the dealer have done it.Change the thermostat,coolant, the expansion tank cap,and check the waterpump if needs changing too.Am I on the right direction?if these bits will not solve the problem i guess i'll take it to the garage for the ignition timing to be checked as the cambelt was also changed when they replaced the thermostat.

Thanks for spending time to read my write up and inputs will be much appreciated.

[oj88]

Not a Volvo owner but did some research anyway. It seems that that particular model had quality issues, based on Wikipedia. Mark 2 sort of fixed some of the issues as quoted below:

The 460 received the following evaluation: "The 460 substitutes a generous boot for the 440's tailgate but is otherwise identical. Liked by older motorists for perceived Volvo strength and safety, but lacks image and now sells for less than the hatchback. Power steering is a must - parking can be heavy going without it. As with the 440, models from late 1993 are best." [5]
Parker's also takes note of problems commonly reported by owners over many years. It summarises the issues found in relation to the 400 series as follows: "Some early cars suffered from erratic build quality; possible rust in body seams; gear linkage failure; overheating; coolant leaks; smoky engine when cold indicates piston wear; possible electrical problems."
It should be pointed out that the data used to create this list came predominantly from owners of the earlier Mark 1 models of the car, with many of these faults becoming much more rare (or disappearing completely) with the introduction of the Mark 2. An auxiliary water pump was added to all non-turbo models from late '93, along with 'run-on' electric radiator fans, which continued to run after the engine was switched off in an attempt to fix the overheating/coolant problems...

Source: http://en.wikipedia.org/wiki/Volvo_460

[afrasay]

check the viscous liquid in your clutch radiator fan. refill it with silicone if needed.

[rst619]

since you have no coolant leaks, then the most possible culprit is poor coolant circulation. If the thermostat is replaced and indeed functioning properly, then you have to check if the water pump is working and if the radiator has no blockage.

but if you have ascertained that there is sufficient coolant circulation, then you have to check the efficiency of your vehicle's cooling system as a whole. maybe the fan is no longer spinning as per specs, radiator fins (those outside) has partial blockage, etc etc. HTH

[poknat]

Thanks for the input fellow tsikooters.I forgot to mention that the fan kicks in as soon as the temperature goes up near the red line and work hard to keep the needle go further.Yes the 400 series have got some issues with overheating but i just loved the car especially the box shape although for some it is boring.I think i'll get on then on my plan to improve the circulation and fingers crossed it will make it better.Also i peek unto the hole where you can check the cambelt and the marker line up with the guide on the cover so thus that rule out the ignition timing?cheers for the inputs again!

[oj88]

I'll tell you what I would do; Look at what design changes they did on the Mark 2 and maybe you could do the same on your 460 (assuming what you have is the Mark 1).

It just occurred to me that the engine may not have been designed for tropical/warm climates.

[bambino]

first thing to do , ipacheck mo yung cylinder head for possible gasket or head blowby .

the best and the most accurate tester ever is the emissions machine , no guessing, it will be able to annalyze the head in few seconds .

if the head is good
then check the coolant circulation for possible water pump impeller problem.

i've seen pumps with worn out and broken impellers .