overheating probs

[keymosaaby]

my 88 900 turbo is constantly overheating. changed themostat and thermo plugs. what would now be the most likely cause, a clogged radiator or bad heater core.

[Tomarse]

Clogged radiator is most likely. The car should still run fine with the heat turned off (and thus the heater core not in the circuit).

Have you tried feeling if the radiator is getting warm all over? Just put your hand all over it (avoid putting hands in fans though!)

Worth running the car without a thermostat (if only briefly) in my opinion to see if it still runs hot then (to rule out faulty stats), and because it will take less time to warm the radiator up so you can feel it for cold spots. You can see what the flow is like then too (and confim the water pump is working properly)

[Matthew]

Did you fit a genuine Saab thermostat? Is the radiator the car's original unit?

[Tomarse]

hmm. another thing to check is the header tank cap. it will run a lot hotter if this isnt sealing up to the correct pressure like it should.
A faulty radiator cap was the difference between boiling over and just running warm on my landrover.

[ProfZ]

If the rad is the original one that came with the car, replacing it is the first thing to do.

You don't say where you are, but if you're in the US, try www.eeuroparts.com for the rad; it's about $130. It's an easy DIY job. Also, replace all of the hoses at the same time; eeuroparts offers the Australian-made Mackay set at 1/2 the price of OEM, and I can recommend this because I installed these hoses in my 1990 900S 4 years ago and they're still fine