overheating question

[scruffy63]

ok I have a 89 240sx coupe (all hail the coupes). my engine tends to overheat in traffic. the clutch on my engine fan died. so I installed an electric fan. so I don't think thats the problem. I think the problem could be my radiator. my resevoir tank has a hole in it (looking for a new one). could this cause low pressure in the radiator? all opinons and answers are appreciated.

[scruffy63]

don't jump too fast too help. anybody wanna give a helping hand.

[ITA240SX]

I doubt your leaky resevoir would directly cause a drop in pressure in the radiator, since it's not part of the pressurized system. It would, however, contribute to the overheating problem in that there's no fluid to be drawn back into the system when the car cools down. I've never had a cooling problem with mine, but my understanding is that it takes very little coolant loss in one of these cars to cause overheating.

Have you checked to make sure your electric fan is cycling on and off? Also, is it a single or dual fan (don't know if it really matters, just thinking out loud)? Are you seeing a coolant loss? Not to be pessimistic, but overheating is often one of the early signs of head gasket trouble. You may want to keep an eye out for signs like water in the oil, missing, decreased performance, etc., although these things are not always present with head gasket failure.

Just a few of the things that came to my mind.

Good luckEarl

[scruffy63]

it is a single fan and it does work it is always on. yes I am seeing a coolant loss. cou this be b/c of a leak elsewhere?

[I am Technoman]

Scruffy how old is your car? If it has the original radiator, replace it along with the thermostat and do a compression test on the cylinders.

[scruffy63]

so is the old radiator actually making it overheat or could it be something else? it is an '89

[sammy]

hey scruffy, be sure to check the top of your radiator, under the overflow hose........that crappy plastic top radiator tends to crack there........you can get a new rad shipped to your door for 115$ from Radiator express........just don't believe their add for the 2 row rad for 145 dollars.....i tried to get that one, and they no longer carry it

[mrp-s13]

Scruffy, I was having the same problem, (First I thought it was my fan clutch, but it turned out to be just fine) eventually it was overheating even when I wasn't in traffic - just driving normally. Blown head gasket. woo fun. I've got a hole in my resevoir still, and I also lost the damn cap for it, yet it cools down fine. (after the head+valve job, that is) I sure hope it's something else for you, this has been a real pain in the ***, and the mechanic still isn't done - car runs like a dog now. *sigh* Brought it back to him this morning.

[U12 2NR]

Replace the radiator? Why?

As long as the coolant has been maintained properly I highly doubt your radiator would have any rust build up or any other sort of build up in it. If the fins of the radiator are clogged with debris, then simply clean it out. It makes no sense to replace a radiator if it's not broken in some way. Radiators don't lose their cooling effeciency, coolant does, which is why we flush coolant every once in a while.

If you've never replaced the thermostat, that would be a good place to start. Take a look at the water pump, there's a little hole on it, see if any coolant is comming out that hole. If your water pump is original, then your coolant loss could be a result of the water pump leaking through the hole.

New thermostat, water pump and new coolant should do the trick. It may sound like unnecessary work because you haven't pin pointed the specific problem, but the water pump and thermostat are both items that get replaced one time or another, so being that you are having cooling issues, now's a good time to replace the two.

[midwestdrifter]

yeah flush that thing. you can get a kit for like 3 bucks. really easy.