84 wagoneer new owner help with overheating

[chappys4life]

Yesterday I picked up a 84 grand wagoneer 360 stock automatic in rough/project condition. The seller told me it was drivable and should make the drive home (checked the fluids before I left)....I should have towed. The trip was 65 miles drive with 75mph driving.

I noticed the stock temp gauge sitting around the 3/4 of the way to hot but was still in the green. Around 25 minutes from home the gauge shot up to the max mark. I pulled it over and steam was pouring out. I let it sit 2-3 hours, added 3 gallons of water and limped it home. Before I was home it was hissing and smoking at the top of the green temp mark. Once home I let it cool down for a few hours, checked the oil (dirty but full) and added more water. Ordered a new radiator and hoses. Checked the belts and fan (fan was spinning) let it idle and it sounded ok, so I took a short drive to see what it did. Now it sounds like it almost has a knock or some kind of mechanical engine noise. The noise changed with rpms so I’m assuming I just got a rod knock.

Does this sound possible? When I looked at the oil it looked dark black but not coolant. When I ran the motor at idle no bubbles or burping. Not sure my next steps and wanted the forums opinions. Should I change the radiator and do a oil change? Or should I be planning a rebuild?

Also does anyone have the belt diagram? I think mine are right, but there is a open spot on the pulleys that has me wondering if I’m missing a belt.

[will e]

Howdy from Phoenix and welcome to the forum. Sorry about the problems but we'll get them worked out.

Since it overheated on the highway it probably isn't a fan or shroud issue. The air pushing through the radiator is enough to keep it cool at those speeds. First thing to check is the thermostat. They are cheap and it's easy to get to. I would take out the old one and drop it into a pan of boiling water to see if it opens. If it doesn't, you've found the problem. If it does, it might still be bad or intermittent and you should swap it out anyways. Test the new thermostat before installing.

Another issue these rigs sometimes have is the lower radiator hose will 'collapse' and block the water flow. This is a bit harder to catch because it normally happens at higher RPM's, not a idle.

I would hold off on a radiator change until you get new belts and hoses.

As far as belt routing. There are three belt routings, one of these three is two belts combined.

The two belts combined go around the crank, water pump, AC Clutch and Alternator.
A single belt goes around the crank, water pump and power steering
The third belt goes around just the power steering and the A.I.R pump. (This is the small belt)

[fulsizjeep]

Welcome to the group. I think I would change the oil & filter and check for any small debris and other fluid (coolant/ATF maybe) in the old oil. Then work on cooling, thermostat, leaks, etc. Does it have a fan shroud? When you dump the coolant, check for oil/atf in there. The fan clutch could be bad. Will e was on point. Good luck!

[letank]

The trip was 65 miles drive with 75mph driving.

welcome, did you notice any drop in temp when driving at a lower speed, like 55mph for a few miles?

what is the color of the coolant? Very good move on waiting a few hours before adding water, that prevent warping the head gasket...

the cooling system is a bit tricky to fill up... the system needs to be burped... basically fill to slightly above the radiator core... at some point when the engine thermostat opens, there will be a surge of coolant because the trapped air will push the coolant out of the radiator top... if you skip that step overheating may occur...

Our gauges are not particularly accurate, what was your oil pressure during the drive?

[rocklaurence]

The guys have nailed the biggest concerns already. I suspect the Tstat and lower hose [hose should have a spring in it to prevent collapsing]. It could also be that half the radiator is full of crap/scale. Take it out and wash/rinse it. The gauge is probable a bad pick-up sending unit--easly to replace. The worse case cenerio is blown head gasket--can check by looking at the plugs.

[chappys4life]

Thank you guys for the input! Went out and let the Jeep come up to temp and the top hose was burning up and the bottom had no water running through it. Looks like a bad thermostat. I ordered a new 180 thermostat, new coolant hoses, and a eBay aluminum radiator (figured I live in Texas so might as well do all 3)

Question on the aluminum radiator I need to get barb fittings for the trans cooler rubber hoses. What size and can I get them at a Napa or some parts store locally? Also what size is the rubber for the trans cooler? While I am here I will change them since they are so short.