FJ60 overheating after new water pump

[peteypbomb]

Hey all,

First post on here, so apologies if I've done it in the wrong forum. My girlfriend recently bought a 1982 FJ60 and we're learning how to work on it together, and we need some answers.

On Saturday, we replaced the water pump and water pump pulley. Lots of nasty, fishy smelling neon green coolant came out when we did. Everything came apart really easily and got everything bolted back together (three times, forgot the shroud and then the belts...), and topped off overflow and rad with new green coolant. It started right up afterwards and ran really well. Took it for a spin yesterday and it overheated really quick. Got it home and let it cool all the way off. Assumed we didn't give it enough coolant, so topped it off again last night, and then it wouldn't start.

The charge light was on and volts were sitting around 10, and would drop down to below 8 when actually turning the key to start. Jumped it with my truck and it started right up, but then just idling it started to get really hot. This was probably 4 hours after it overheated, and it was 30 degrees out. Gave it more coolant again, and let it cool off. Haven't tried to start it yet today.

Before Saturday, it had been sitting since October 14th, so would make sense that the battery might be a bit dead. It's also started to get really cold here in Utah.

TLDR; Are we just dumb and haven't added enough coolant yet? A LOT came out when we pulled the water pump off. We've put 2 gallons pre-diluted green in there so far. Typically it runs really cold and barely jumps over the C on the temp gauge.

Any tips or answers or knowledge for these newcomers would be much appreciated. Cheers!

 

[OSS]

All 2F engines will show higher temperature on the stock temperature gauge for about 2 weeks of daily driving after draining & refilling coolant.

There’s two theories as to why, and my suspicion is that it’s a combination of the two:

1. Draining & refilling the coolant creates air pockets underneath the head that interfere with proper cooling (this is a fact) until the air bubbles eventually work their way out.

2. After coolant change, the temperature sender will most definitely develop a bubble around it, insulating it from the coolant, so it registers the actual temperature of the cast iron head it’s screwed into instead of the coolant it’s supposed to be fully immersed in.

But whatever the reason, there’s hope. Just drive the car frequently for about 2 weeks and it will sort itself out.

Pro Tip: Burping the radiator after a coolant change can get rid of a lot of the bubbles.

 

[rawrt]

Welcome.
You may have some air trapped in the system. You might need to get the frontend up on some stands or blocks under the tires to help the air escape. Take the cap off the radiator and let it work some coolant around and watch for bubbles. The coolant capacity is around 17 quarts.

Did you tighten up the belts when you were done? I cant remember which 1 of the 3 belts is with the alternator and water pump. Maybe have your battery load tested if you have to run to the store for more coolant.

 

[jayp2]

I always put the front on a little bit of an incline facing up and turn the heat on and bring up to temp

I also do an initial fill via the return hose which is a high point given the above orientation on incline which helps to minimize any of the issues

Once the head/block is full, reattach the hose to top of radiator and cant remember last time it wasnt good to go after doing remainder of fill of radiator thru the cap

Usually only requires a splash more coolant after running up to temp a couple times and never had any temp issues

 

[peteypbomb]

Welcome.
You may have some air trapped in the system. You might need to get the frontend up on some stands or blocks under the tires to help the air escape. Take the cap off the radiator and let it work some coolant around and watch for bubbles. The coolant capacity is around 17 quarts.

Did you tighten up the belts when you were done? I cant remember which 1 of the 3 belts is with the alternator and water pump. Maybe have your battery load tested if you have to run to the store for more coolant.

I did tighten up the belts, yep. We only have 2 belts - one goes Alternator - Power steering - Crank, other goes Water Pump - Smog - Crank.

I'll pop the rad cap and run it for a bit this afternoon.

 

[peteypbomb]

All 2F engines will show higher temperature on the stock temperature gauge for about 2 weeks of daily driving after draining & refilling coolant.

There’s two theories as to why, and my suspicion is that it’s a combination of the two:

1. Draining & refilling the coolant creates air pockets underneath the head that interfere with proper cooling (this is a fact) until the air bubbles eventually work their way out.

2. After coolant change, the temperature sender will most definitely develop a bubble around it, insulating it from the coolant, so it registers the actual temperature of the cast iron head it’s screwed into instead of the coolant it’s supposed to be fully immersed in.

But whatever the reason, there’s hope. Just drive the car frequently for about 2 weeks and it will sort itself out.

Pro Tip: Burping the radiator after a coolant change can get rid of a lot of the bubbles.

Thanks for this, hope indeed! I'm guessing this 'false reading' is what would lead it to say it's getting too hot when it's idling? Because it definitely did actually overheat after we drove it, likely do to a lack of coolant? Will try to bubble some coolant out today and take another spin around the block.

 

[peteypbomb]

Thanks for this, hope indeed! I'm guessing this 'false reading' is what would lead it to say it's getting too hot when it's idling? Because it definitely did actually overheat after we drove it, likely do to a lack of coolant? Will try to bubble some coolant out today and take another spin around the block.

Bubble out some air* not coolant

 

[peteypbomb]

All 2F engines will show higher temperature on the stock temperature gauge for about 2 weeks of daily driving after draining & refilling coolant.

There’s two theories as to why, and my suspicion is that it’s a combination of the two:

1. Draining & refilling the coolant creates air pockets underneath the head that interfere with proper cooling (this is a fact) until the air bubbles eventually work their way out.

2. After coolant change, the temperature sender will most definitely develop a bubble around it, insulating it from the coolant, so it registers the actual temperature of the cast iron head it’s screwed into instead of the coolant it’s supposed to be fully immersed in.

But whatever the reason, there’s hope. Just drive the car frequently for about 2 weeks and it will sort itself out.

Pro Tip: Burping the radiator after a coolant change can get rid of a lot of the bubbles.

Welcome.
You may have some air trapped in the system. You might need to get the frontend up on some stands or blocks under the tires to help the air escape. Take the cap off the radiator and let it work some coolant around and watch for bubbles. The coolant capacity is around 17 quarts.

Did you tighten up the belts when you were done? I cant remember which 1 of the 3 belts is with the alternator and water pump. Maybe have your battery load tested if you have to run to the store for more coolant.

Alright, an update: When I went out to the truck, the overflow was very low, so added some more coolant to that. Started the truck with the radiator cap off and let it run for a few minutes. No bubbles out of the radiator, so put the cap back on. Kept an eye on temp gauge and it was slowly climbing, but the trusty "stick your hand in the engine bay" didn't feel super hot in there. After a few minutes, the overflow tank was bubbling a lot and steam was coming out when I took the lid off. Air was blowing out of that little straw that hangs down in there. Turned the truck off and let it cool cause we got freaked out. We were also hearing a weird drip and burn hissing noise up near the thermostat that would get worse if we squeezed that hose. Not the one that connects to the radiator, the other smaller one.

Waited a couple minutes and turned the truck back on, with the radiator cap off again. This time it was bubbling and steaming a lot out of the radiator, spitting out coolant and steam. Is that what we're looking for "burping" it? Or is something else wrong. Don't know if I can attach videos here, but I have some of what was going on. Lemme know! Thanks for your help, really appreciate it.

 

[SteveH]

After a few minutes, the overflow tank was bubbling a lot and steam was coming out when I took the lid off. Air was blowing out of that little straw that hangs down in there.

Are you using a new, quality radiator cap with un-cracked gaskets? If not, don't do any more troubleshooting until you do. The system depends on the pressure contained by the cap (and the secondary gasket to get the coolant to the coolant bottle) to work properly.

After you buy a new cap, fill the radiator to the top, install the cap, fill the coolant bottle, run the truck (preferably driving) until it's hot, and then park it and let the whole thing cool down overnight (until dead cold) and suck coolant out of the bottle. Monitor this over a few days time, adding to the bottle as needed.

 

[peteypbomb]

After a few minutes, the overflow tank was bubbling a lot and steam was coming out when I took the lid off. Air was blowing out of that little straw that hangs down in there.

Are you using a new, quality radiator cap with un-cracked gaskets? If not, don't do any more troubleshooting until you do. The system depends on the pressure contained by the cap (and the secondary gasket to get the coolant to the coolant bottle) to work properly.

After you buy a new cap, fill the radiator to the top, install the cap, fill the coolant bottle, run the truck (preferably driving) until it's hot, and then park it and let the whole thing cool down overnight (until dead cold) and suck coolant out of the bottle. Monitor this over a few days time, adding to the bottle as needed.

Old rad cap was indeed pretty cracked and dried out in there. Got a new one that fits, psi on the spring might be a bit higher though. Did as you said, drove her around the block a few times and now she's tucked in to sleep. Will report back. Also noticed after our drive that the thermostat hose I mentioned earlier was in fact leaking at the end. Tightened it down and will order a replacement.

 

[OSS]

If there’s still a lot of air in the system, the bubbles migrate to the radiator and air collects at the top of the radiator as the bubbles join up. When the radiator cap opens when the pressure builds up to its rating, that air in the top of the radiator gets purged out into the overflow tank.

Then when the engine cools down, the cooling system contracts and sucks coolant back up the overflow tank straw and into the radiator.
Over time, this is how the engine purges itself of air: A sealed cooling system heating up and cooling down several times.

 

[sark]

I bought this kit when I refilled my radiator on my 73 and had no issues with burping:

https://www.amazon.com/dp/B01I40ZQWE

 

[CJF]

Typically it runs really cold and barely jumps over the C on the temp gauge.

That's not good either.

You sure this rig was in good, or at least acceptable, running condition before the water pump replacement??

 

[CJF]

Double tap

 

[CJF]

Triple...

 

[peteypbomb]

That's not good either.

You sure this rig was in good, or at least acceptable, running condition before the water pump replacement??

Hmm well she's only owned it for a few months, and it wasn't running until shortly before she bought it. So definitely not in tip-top shape, but seemed to be running quite well. Took it on numerous camping trips without any issues.

What would running cold like that indicate? is that a symptom of a specific problem?

 

[884runner]

Definitely get a funnel like linked above to burp the system good. Those are good to have when changing the coolant on anything.

 

[mblakec]

Hmm well she's only owned it for a few months, and it wasn't running until shortly before she bought it. So definitely not in tip-top shape, but seemed to be running quite well. Took it on numerous camping trips without any issues.

What would running cold like that indicate? is that a symptom of a specific problem?

My cruiser temp gauge would barely get above the C when I first got it. The thermostat was bad. As a result, the heater could barely put out hot air. I replaced the thermostat and after that my truck got up to “normal” operating temperature and the heater worked much better.

Replacing the thermostat was much easier than the water pump, so you guys should be able to manage it fine. I did break one of the 4 studs that hold the thermostat housing together. I think this is fairly common due to the studs getting a bit corroded over time. So be careful there and consider just buying new ones ahead of time.

 

[klinetime574]

This just sounds like a big air pocket with a case of MOTS (MUD Over Thinking Syndrome). I would echo to replace the thermostat if condition is unknown. Make sure to get/install the rubber gasket that sits on top of it which seals it against the upper thermostat housing.

My method of filling the coolant is getting the radiator cap as the highest point in the system. Fill engine cold and squeeze the upper radiator hose between adding coolant. You will see bubbles as you do this. You could get a “spill free funnel,” not sure if they fit stock radiators or not though. I just use a small funnel that fits in the radiator neck.

Example of a spill free funnel:

Now I kinda want to buy one. I convinced myself apparently.

HTH

 

[tristatechimney]

Ok, I've got a weird one, semi related. Have a 85 60 with rebuilt motor, bad rebuild requiring head to be reworked by reputable shop. 7000k miles since second round on head. Wasn't aware of slow coolant drop that caused a quick overheat. Temp gauge pegged. Pulled over to cool, limped home 10 miles home. Next morning no visible leaks. Replaced thermostat and sender unit. Flushed coolant and ran on incline many times with burp funnel. Engine runs fine, yet temp is hovering on the high side. IR gauge reading 180 at thermostat manifold. Compression test 1 - 145 (plug clean), 2 - 135 ( fouled ), 3 - 135 ( fouled ), 4 - 140 ( fouled ), 5 - 135 ( fouled ), 6 - 150 (plug clean). Loosing a little coolant, inch in overflow every 300 miles.