IdahoSkies

I have a 1992 5.8 V8 F150 XLT. 67,000 miles. (I inherited it from my grandfather a few years ago and he did not drive it much). It has consistently run a bit warm. The temperature gauge generally sits in the middle of the M in Normal. And if I had to drive up a steep hill, it would climb a bit higher, into the gap between the M and the A. But it has never been straight up like in my other vehicles.

Recently on a trail drive it got really hot, above Normal and toward the red. I did the defrost trick, and got it home. Driving over 35 I could keep the temperature down, but stopping for lights or idling, it went up.

I thought the problem was the fan clutch and replaced that tonight. I drove it around and it seemed to be okay, but the gauge now seems to want to sit between the M and the A, and for a short period of time I thought it was going to overheat again, but it settled down.

Coolant was flushed a few years ago, and the levels are at the reservoir line, and the color is good. There is no coolant leakage beneath the vehicle. There are a few dings in the radiator but generally it looks good. I do not see any leakage around the radiator cap either.

I'm wondering the following:

1. Do any of your vehicle's "run hot", or is this a sign of a bigger problem.
2. If its a bigger issue, what should I be looking at? Water pump? Thermostat? Gauge problem?

Thanks for the assist.

88xlt

I think you did the right thing in replacing the fan clutch. I think the thermostat is probably keeping it up to the current temperatures you're getting. It really isn't running all that hot.

If you want it to run cooler you could replace the thermostat. A 195 degree thermostat is recommended. If you replace it with another 195 degree it may run a bit cooler depending on the individual thermostat. A 195 degree is recommended, but you probably would be okay with a 180 if you prefer it to run a bit cooler. Some people claim the sensors and stuff don't work right if you don't run a 195 degree thermostat but I don't know.

One other thing you might do is check where the air flows through the radiator and AC condenser and make sure that is reasonably clean. You could flush it with water, but have the engine cool when you do it.

raski

BTW- my truck runs between the M and A. It used to run hotter until I changed the fan clutch. First I would replace the stat with the same rated "OEM" stat. Some replacements are junk.If your 92 has the original radiator, it might be time for replacement. I would not put a cooler stat in it. It will affect CTS operation, especially when it gets cooler and the temperature will eventually creep back up to the same level with the cooler stat but at a slower pace.

IdahoSkies

To replace the thermostat do I need to drain the coolant like with the waterpump?

88xlt

The best way would be to drain maybe a gallon and a half of coolant out, that would put you below the level of the thermostat. No need to drain all the coolant.

seagiant

Hi,
Take the water hose and spray the radiator in the front and wash all the dirt and bugs out!

You can spray with a degreaser before the hose!

You might be surprised!

Lazarus-F150

If you decide to change the thermostat then I would recommend the 195, but there is also a 192 version available on Rockauto. I would avoid the 180 since the PCM won't transition into closed loop since it will see coolant temp of 180 as "not having reached normal operating temperature).

You could also have a small crack in the head gasket. Have you done the easy tests to check (excess pressure in the cooling system and oil color)? If not, try those too (http://troubleshootmyvehicle.com/for...-head-gasket-1).

IdahoSkies

Thanks for the help. I ordered a 195 thermostat and water pump, (If I'm going to drain the coolant for the stat I might was well do a flush and do the pump too.). I drained the coolant (I only got out a gallon and a half, way to little), and then went to drain the coolant in the reservoir and it didn't drain. I pulled out the reservoir, emptied it from the top and disconnected the reservoir hose. It was clogged right below the nipple and the reservoir bottom was full of sludge. I believe I have been running low on coolant and it has not been replenished because of the clog. I cleaned it and put it back together.

The next morning and I went ahead and started taking out the thermostat. First bolt (the lower one), broke right off the head. The upper bolt came out find. I spent the rest of the day trying to get the bolt out. Penetrating oil, check. Torch, check. V
vice grips, check. Socket style Bolt extractor's, check. Center drill and EZ-out, check. All to no result. At this point I got some help and we decided to just drill the whole bolt out and trying and retap it. No go, the drill wandered off the steel and into the aluminum of the manifold. We thought we would try a helicoil. Also no go. The end result is I know of a slot in my intake manifold instead of a bolt hole. Most of the bolt is now out, but there is now no threads, and there is still a chunk of bolt in it.

Current plan is to mix up some JB weld and fill the slot, and add a bit around it, and try a redo drill and tap for some new threads. Ug. Should have been a 10 minute job.

raski

That sucks. The JB would work if the area is perfectly clean. Also, you need to get that piece of the bolt out first because it will not allow you to drill a new hole and tap the threads.

Eric Fullerton

Probably a bit late now, but for when you break off a bolt, they sell left handed drill bits. Harbor freight sells a set of them for cheap. If there is any way to get the remaining bit of bolt out it will make restoring the hole all the more possible. I'd either helicoil once you have a clean hole or just glue a stud in. before you glue clean it well, like with denatured alcohol or some powerful solvent. I think I like the helicoil the best as it requires a bigger hole and might actually catch some of the remaining aluminum. Either way, a stud over a bolt.