Hi, I have a 94 940 Turbo wagon and on a few occasions, only after turning the car off, coolant leaks down the driver side of the radiator from the upper hose (which is new) the first time I was able to tighten the hose clamp, cleaned the area, and it was fine for a month. (figured that the clamp was just loose) then in the last two weeks, I have had it leak twice, under the same circumstances, from the same area. Seems to only happen when it is VERY hot outside, and the car has been running a while. It does not run hot or anything, but after a situation like that, once I park and turn the engine off off, about a 1/4 cup of coolant leaks out from the same area. Any thoughts/ideas? Thanks.

 

I'd take a real good look at that hose-it may have a flaw or a cut inside at the point where it goes in the radiator... You have to drain a little coolant and take off the hose to do that...

 

Hey, thank you for the advice, I will check tomorrow, it leaked a little today again, Is the seam between the plastic tank and the core in the area of the upper hose a common place for the radiator to leak? I ordered a new upper radiator hose (was cheap enough) and i'll replace it, if it leaks again, i'll just have to replace the radiator I guess...

 

The stock aluminum/plastic radiator does a great job of dissipating heat. I've heard horror stories of them bursting in cold climates when the thermostat opens and 200 degree coolant hits the tanks tho'. Not very often...Assuming the new hose doesn't resolve the leak, make certain the overflow bottle has the correct psi cap. If you do replace the radiator, consider getting a 3 row all metal radiator. They are essentially the same price and are a definite plus with turbo cars especially. On the plastic tanks, I've used emory cloth before and scuffed up the plastic neck to make it less slick in an effort to keep hoses from leaking. I've also crushed a plastic neck from overtightening the cat clamp so...

 

OK so I just realized that the coolant cap on the reservoir tank is that higher PSI grey cap rated at 21.8 psi (150kPa) so I am thinking that this is the source of my issues?? from what I have read it should have the black 75psi cap on it.

 

No, the grey cap is correct. The black caps are for 240's. 22psi is correct for 7/9's. The cap may not be any good, but it is the correct one for your car. Never hurts to replace it if you don't know how old it is. Cooling systems are important; especially so for turbos. Here's the FCP link... http://www.fcpgroton.com/product-exe...category_id/88

 

hmmm, I found this on the IPD website... "When replacing a faulty radiator keep in mind the stress put on the other heating/cooling components. The overflow bottle caps have a pressure rating and it is important to match the correct cap with the radiator. We do not recommend using the higher pressure (gray, green or white 150 KPa) caps as the higher pressures can cause your radiator and hoses to fail prematurely."
link : http://www.ipdusa.com/Volvo-940960/H...p-136-274-418/

 

You can use a lower pressure cap...just means it would boil back at a lower temperature. My personal experience has been that as long as the cooling system is healthy the 22 psi cap is fine. The real question would be if the cap you have vents at 22 psi. You might consider buying some cooling system dye. It's quite possible the radiator itself has a hairline crack.