Tacoma Overheating Problem

SARMARK · 08-06-09, 10:59 PM

I gave my son my 1998 Tacoma with about 250,000 miles. I bought it new and it has had regular service since new. Recently it started overheating at highway speed 70 mph after about 1/2 hour. It does not overheat if he drives slowly. He had the radiator flushed and tried taking out the thermostat but no luck. I would really appreciate any ideas you may have. Thank you very much. Mark

locrwln1 · 08-07-09, 07:23 AM

My cruiser was doing the same thing, new fan clutch fixed mine, especially if you have never changed it out. They are a very under-appreciated, but important portion of the cooling system.

Jack

WILLD420 · 08-08-09, 01:03 AM

The water pumps go south also. I got a new Toyota one for mine at 100K since the old one was leaking.

Don't let it get too hot, or you'll be spending a lot of $$$ on a new engine. The heads don't like to stay flat if you cook it good more than once.

SARMARK · 08-08-09, 11:06 AM

Thank you. He is going to start eliminating one item at a time. I sent him some information about how to check the clutch fan to see if it is working. I don't know what to tell him about the water pump. The pump is not making noise so I don't know how he can check it. Again thanks for the ideas. Mark

rusty_tlc · 08-08-09, 10:02 PM

Quote:

Originally Posted by SARMARK

Thank you. He is going to start eliminating one item at a time. I sent him some information about how to check the clutch fan to see if it is working. I don't know what to tell him about the water pump. The pump is not making noise so I don't know how he can check it. Again thanks for the ideas. Mark

The way I check a water pump is to take the belt tension off and check for play in the shaft, there should be little or no play.

FWIW I'm putting my money on the fan clutch from the symptoms you describe. A bad water pump would over heat at any speed.

chicago · 08-09-09, 12:50 PM

Quote:

Originally Posted by rusty_tlc

The way I check a water pump is to take the belt tension off and check for play in the shaft, there should be little or no play.

FWIW I'm putting my money on the fan clutch from the symptoms you describe. A bad water pump would over heat at any speed.

X3 on the fan clutch!
Water pumps will usually leak as well.

K

SARMARK · 08-09-09, 02:35 PM

You guys are the best. I really appreciate the tips. I looked up prices today and it looks like a water pump is about $90. and a fan clutch about $120. I will hope for the water pump because of price. He is on a tight budget so I am going to try and help him get it fixed. I told him we would need to change the hoses and belts while we were at it. The article I read on fan clutches said something to the effect, if you can't turn it it is bad - if you can turn it too freely it is bad - it should have some drag but not spin freely? If you guys have anymore ideas please keep them coming, Thanks Again, Mark

rusty_tlc · 08-09-09, 09:03 PM

Quote:

Originally Posted by SARMARK

You guys are the best. I really appreciate the tips. I looked up prices today and it looks like a water pump is about $90. and a fan clutch about $120. I will hope for the water pump because of price. He is on a tight budget so I am going to try and help him get it fixed. I told him we would need to change the hoses and belts while we were at it. The article I read on fan clutches said something to the effect, if you can't turn it it is bad - if you can turn it too freely it is bad - it should have some drag but not spin freely? If you guys have anymore ideas please keep them coming, Thanks Again, Mark

I'd do some searching on Mud, I believe there is a test that involves using a newspaper to see if you can stop the fan when the engine is cold and when it is at temp.

I also seem to recall that you can rebuild the fan and just replace the clutch rather than replace the whole assembly. The Toyota parts place will give you the part number for the whole fan, not just the clutch, because that is how they repair it in their service dept.

locrwln1 · 08-09-09, 09:10 PM

Quote:

Originally Posted by SARMARK

You guys are the best. I really appreciate the tips. I looked up prices today and it looks like a water pump is about $90. and a fan clutch about $120. I will hope for the water pump because of price. He is on a tight budget so I am going to try and help him get it fixed. I told him we would need to change the hoses and belts while we were at it. The article I read on fan clutches said something to the effect, if you can't turn it it is bad - if you can turn it too freely it is bad - it should have some drag but not spin freely? If you guys have anymore ideas please keep them coming, Thanks Again, Mark

The problem with the fan clutches are that the silicon, like any other fluid breaks down over time. Silicon is what "locks" the fan up at high heat situations.

My money is still on the fan clutch. My 80 was overheating at highway speeds and would run cool as a cucumber at idle or in town speeds. As soon as I would start pulling a hill at highway speeds, up she went all the way to boiling over. Chased my tail trying everything but the fan clutch. I even have an electric "pusher" fan on mine. Replaced the fan clutch and now no matter what I do, 190-195 degrees is all that it will get up to. That is A/C on/hill climbing/70+ mph.

Good luck,

Jack