1983 FJ60 coolant system flush and overhaul

[fjgdk]

My stock Fj60 runs hot when in low gears/slow speeds with the heaters off. It cools down when I speed up or when I open the heaters up and am driving.

I wanted to simply redo the coolant system with a new thermostat, water pump and cleaned-radiator. Before I dive into it, I of course have some questions.

1) What is the best way to flush the system such that once done everything old is removed from the radiator, block, front and rear heaters ? I understand to unplug the rad petcock and block plug, but there is still gunk in the front and rear heaters.
Can I unplug both the petcock and block plug with the heaters open and put hose water through it while running the engine or will I kill the engine with heat as the block plug will still be open ?
Should I instead unplug the two and drain, close the plugs back up, fill with water and run the engine until the thermostat opens and then turn off, unplug, drain, plug and repeat until all I get is clear water ?

2) Should I flush the system before AND after I install everything new or just afterwards. Was thinking both before and after because I don't want to contaminate any of the new or cleaned stuff with old coolant in the flushing processes afterwards.

3) For these old FJ60's, is the typical Prestone green w/ distilled water a "high quality" antifreeze per the FSM?

4) Has anyone ever rebuilt the water pump ? I am replacing mine but wanted to rebuild the old one in case of an emergency. I can get the OEM rebuild kit for less than $30 but I am not sure if taking out and pressing in the bearings is doable without the SST from the "water pump rebuild tool kit" mentioned in the FSM.

5) Has anyone ever had their rad cleaned with a "thermosonic" cleaner ? One local rad shop suggested that before rodding. Is it effective enough ?

6) Where in any Toyota manual does it describe how to actually take off these parts ? There is a heater section in the FJ60 "body and chassis manual" and a bit about the thermostat, radiator and water pump in the 2f manual, but neither shows removal of any of the said parts. just how to take them apart or diagnose replacement once removed.

7) Are the hoses going into the firewall for the heater in the correct position ? I don't think they are. How much of an effect on my coolant system did this have if in fact it is incorrect .

 

[fjgdk]

Let me add one more question:

8) Would using a sump pump to flush the coolant system components provide too much pressure to the various heat exchangers (rad, heater core etc.) on my FJ60 ? I saw a video here on mud of someone doing it, it seemed like a good idea as he flushed the heaters individually from the block and rad that way. If I were to do this, I don't know what pressure/hp from the sump pump will be too much.

 

[fjgdk]

Here is the sump pump flushing video:

Radiator flushing video

 

[TexasBlue]

Research this forun on flushing the system. Not hard but the cruusers have 17 plus quart cooling system.

The hoses circled are connected correctly to the front heater control valve. Some import items to do- make sure you completely drain system from the radiator and the block drain..located on the DS lower part of the engine block.

After you fill system, I use a 50/50 mix of Prestone with water to 'burp' the system to get rid of ait pockets. That's easy. Simply run the engine 1300-1500 rpm with heat at full blast for both front/rear heat and top off the coolant while running.

Hope this helps.

 

[fjgdk]

Thanks for the reply.

1) I've done some researching on mud and google in general, I haven't had my understanding cleared up though which was why I was asking #1.


2) My concern was with the positioning of the hoses as the connect to the firewall. You will notice on my truck the hose is from the heater control valve to the top of the 2 firewall hose ports. In the parts diagram, it appears that this hose should connect to the bottom of the firewall ports. Is my truck screwed up in this regard ?

 

[gregnash]

The parts that you have circled ON the firewall are actually the pipes through the firewall from the front heater core. To get that you have to take a large majority of the dash apart to get it out.

 

[OSS]

This is my advice:
Drain the coolant. Replace the radiator, fan clutch & thermostat. Fill back up with 50/50 green coolant, burp the bubbles & forget about it.

Whatever crap that can circulate in the cooling system has already lodged on top of the old radiator.

Back flushing an old radiator just flushes
all that debris back into the water jacket of the head & block, where some of it -might- get drained out of the drain spigots.

The Toyota maintenance manual never recommends back flushing or flushing the cooling system. Just drain & fill for the life of the vehicle.

My 60 has almost 300k miles on it & the cooling system has never been "flushed" or "back flushed". Just drain & fill according to recommended intervals. Radiator, fan clutch & thermostat have been replaced. No problems.

 

[TexasBlue]

Your pic is correct. The hoses are suposed to be connected that way. Gregnash thanks for the technical bit..haven't had to tear into my dash yet....

 

[fjgdk]

The parts that you have circled ON the firewall are actually the pipes through the firewall from the front heater core. To get that you have to take a large majority of the dash apart to get it out.

Yes the area I circled are hoses in the engine bay that connect to the heater core which is deep inside the dash. My question is concerning the hoses in the engine bay that are connected to the heater core via pipes on the firewall. Should the heater control valve hose be on the top or bottom pipe of the heater core ? You will see that my truck has this hose on the top but the diagram shows the firewall hose to be connected to the bottom. I think my truck is set up wrong.

 

[TexasBlue]

That is expensive suggestion. Radiator, fan clutch and thermostat would be over $500.00. Sorry I recommend starting with flush, change thermostat n gasket

 

[TexasBlue]

Yes the area I circled are hoses in the engine bay that connect to the heater core which is deep inside the dash. My question is concerning the hoses in the engine bay that are connected to the heater core via pipes on the firewall. Should the heater control valve hose be on the top or bottom pipe of the heater core ? You will see that my truck has this hose on the top but the diagram shows the firewall hose to be connected to the bottom. I think my truck is set up wrong.

Nope my 85 is same

 

[fjgdk]

Your pic is correct. The hoses are suposed to be connected that way. Gregnash thanks for the technical bit..haven't had to tear into my dash yet....

I've actually torn out the heater core, AC evaporator, fan etc. in the dash (I've seen those pipes and the rubber piece that protrudes from the inside to the firewall), but yes I am still asking for help on a basic thorough flush.

When I first got the truck it had been sitting and there was a dead rodent problem, so I took everything out of the dash. It is a nightmare job. I removed coolant only by the petcock and block and replaced it when done. It wasn't really a "flush" and there was still enough coolant in the heater core to make a mess when I disconnected it and took it out. I was more concerned with a cleaning of the core, evaporator and the boxes they were contained in. I had an AC guy extract and replenish the R12 before and after I did it all. The diagram I circled in red on is from that job when I was trying to put some new hoses on at the same time.

Also, I was the person who connected those hoses the way they are in the picture. It is the way they were when I took them off to do the de-mousing. When I did this 5 years ago I remember questioning if it was correct back then. I didn't know of MUD back then to ask the question.

 

[fjgdk]

That is expensive suggestion. Radiator, fan clutch and thermostat would be over $500.00. Sorry I recommend starting with flush, change thermostat n gasket

OEM thermostat and water pump from Amayama will be less than $200 ($147 + shipping which they haven't gotten back to me with). The radiator rodding/cleaning I was quoted about $150.

 

[TexasBlue]

Cool I did same for my radiator. Figured it would save $$. You may consider the fan clutch too.

 

[fjgdk]

This is my advice:
Drain the coolant. Replace the radiator, fan clutch & thermostat. Fill back up with 50/50 green coolant, burp the bubbles & forget about it.

Whatever crap that can circulate in the cooling system has already lodged on top of the old radiator.

Back flushing an old radiator just flushes
all that debris back into the water jacket of the head & block, where some of it -might- get drained out of the drain spigots.

The Toyota maintenance manual never recommends back flushing or flushing the cooling system. Just drain & fill for the life of the vehicle.

My 60 has almost 300k miles on it & the cooling system has never been "flushed" or "back flushed". Just drain & fill according to recommended intervals. Radiator, fan clutch & thermostat have been replaced. No problems.

Thanks for the reply. Good to hear of another 60 with nearly or more than 300k original miles. Mine is at 285k.

I appreciate the input, but I do want to argue academically here a bit on the backflushing done in the video. The guy back flushes piece by piece:

1) disonnect heater core input and output - flush
2) disconnect block input and output - flush
3) flush radiator only input and output


It seems that since each component is isolated in the flush that the bad stuff can't go from the rad to the block or heater. Am I wrong ? I don't know if I am right I am just asking hypothetically speaking.

 

[bhk]

OEM thermostat and water pump from Amayama will be less than $200 ($147 + shipping which they haven't gotten back to me with). The radiator rodding/cleaning I was quoted about $150.

Why are you going through Amayama? Parts are still available in the US for ~$110.

Also, the problem sounds more like the fan clutch. If you're going to redo your whole cooling system, I'd recommend doing it too while you're at it.

 

[fjgdk]

Why are you going through Amayama? Parts are still available in the US for ~$110.

Also, the problem sounds more like the fan clutch. If you're going to redo your whole cooling system, I'd recommend doing it too while you're at it.

Ok I see that toyotapartsdeal.com seemingly has the pump in stock for $75. I'll check it out. I wasnt finding any kf my US based sites tonhave it in stock.

As for the cooling fan, it seems to be spinning as it should. The other day when it was high 90's it came ok immediately with a cold start. I've checked it when driving (well I stop on the side of the road) and it is going.

When I look inside the rad it doesnt seem like anything is moving. I think the issue is a stop in the circulation system - thermostat, pump or clogged rad.

 

[bhk]

The fan will spin even if the clutch is bad. Audible is one cue, the roar is pretty loud when engaged. The other way is to get the engine hot and then shut it off. If the fan stops immediatly, it's good. If it continues to spin, it's bad. Some people will recommend sticking a rolled up newspaper into the fan; if it stops, bad clutch. If it chops up the newspaper, good.

 

[fjgdk]

The fan will spin even if the clutch is bad. Audible is one cue, the roar is pretty loud when engaged. The other way is to get the engine hot and then shut it off. If the fan stops immediatly, it's good. If it continues to spin, it's bad. Some people will recommend sticking a rolled up newspaper into the fan; if it stops, bad clutch. If it chops up the newspaper, good.

Oh this is good to know. I will check this later today. I will go with the "heat up and shut off" method.

 

[gregnash]

Ok I see that toyotapartsdeal.com seemingly has the pump in stock for $75. I'll check it out. I wasnt finding any kf my US based sites tonhave it in stock.

As for the cooling fan, it seems to be spinning as it should. The other day when it was high 90's it came ok immediately with a cold start. I've checked it when driving (well I stop on the side of the road) and it is going.

When I look inside the rad it doesnt seem like anything is moving. I think the issue is a stop in the circulation system - thermostat, pump or clogged rad.

No need to go anywhere else other than @beno (Onur) for all your OEM parts.

And yes the fan clutch makes LOTS of noise when engaged.