Hi Mudders,
Maybe someone can help who has seen this show before. I did a 1Hz 4.2 diesel swap on a FJ62 (removing a 3f) a while back.
I had some electrical gremlins I managed to sort out, and a number of air leaks (including one on the fuel pickup inside the tank) which caused all sorts of drama, but I finally got to the bottom of it. The Engine was a supposedly refurbished engine from Japan, that was imported by the Toyota parts experts at Gemini in Johannesburg CBD. I honestly thought I had gotten the build stable as the engine itself had given no troubles for close on 15,000km of roadtrips and adventures.
My issue is the vehicle started overheating on long, strained uphill drives (this prior had only happened 3 times, all on stinking hot days running the aircon at the same time, but now is happening on any sustained long hill). I have a big hill by my house that I cannot drive up without the temp gauge going over 3/4, and over a 100 degrees when tested with the laser at the top of the hill. I had tried to take her up to the Drakensberg mountains, but just the steep sustained uphills leaving the beach the car ran to red-line and I had to stop and head home to get another vehicle. She ran cool as soon as I got onto the downhill again and removed the strain. If just driving around the city and normal strain, or even idling for hours it never climbs above half.
Here is the shopping list of things that were done:
1) Re-cored the original radiator at the time of the engine swap (ex 3F radiator) - and flow rate is good when tested recently (and we are doing some more detailed tests on it this week to make sure its not undersized for the diesel vs. petrol -- is this an issue that diesel needs more cooling than petrol??) No rust issues, or blockages we can see.
2) Tested the fan viscose coupling - seemed to be working well. But also serviced it with new silicone oil. Plus, tested her with a known working fan with a bigger diameter off another cruiser... still overheating. Also tried with the Shroud removed just in case that was the issue, but no assistance.
3) Replaced the Thermostat... I did find a number of holes drilled in the old thermostat (pointing me to think this is not the first time this engine has had overheating issues). Replacement is OEM from Toyota, and the parts guy said it was tested at the factory before they dispatched it to me. (We have not tried running the car with no thermostat at all... but the holes drilled in the old one - see pic below - make me think its not going to solve this issue)
4) Radiator Pipes are all newish and in good condition with no buildup or blockages.
5) Checked the water pump (metal blades) and all seems to be working appropriately and its definitely circulating
After doing all of this...
6) finally removed the head... there was a leak in the head gasket (see images below)... so we skimmed the head to get it smooth at an engineering shop and put the head back on with a thick gasket.
7) Sent the cruiser in to an Injector Pump specialist to check the timing was all good, and we were not overfueling. He did retard the timing some what, but the same issue remains.
I hoped no. 6 was the final step, but alas she is still overheating on sustained up hill drives at high revs... The car starts first time on a dime, and runs smoothly.
Anything I am missing - please help!! @roscoFJ73 you have been one of the most knowledgeable people I have encountered here around the 1HZ. Any ideas?
I attach some pics below for reference of the Thermostat removed, and the head off the engine
Maybe someone can help who has seen this show before. I did a 1Hz 4.2 diesel swap on a FJ62 (removing a 3f) a while back.
I had some electrical gremlins I managed to sort out, and a number of air leaks (including one on the fuel pickup inside the tank) which caused all sorts of drama, but I finally got to the bottom of it. The Engine was a supposedly refurbished engine from Japan, that was imported by the Toyota parts experts at Gemini in Johannesburg CBD. I honestly thought I had gotten the build stable as the engine itself had given no troubles for close on 15,000km of roadtrips and adventures.
My issue is the vehicle started overheating on long, strained uphill drives (this prior had only happened 3 times, all on stinking hot days running the aircon at the same time, but now is happening on any sustained long hill). I have a big hill by my house that I cannot drive up without the temp gauge going over 3/4, and over a 100 degrees when tested with the laser at the top of the hill. I had tried to take her up to the Drakensberg mountains, but just the steep sustained uphills leaving the beach the car ran to red-line and I had to stop and head home to get another vehicle. She ran cool as soon as I got onto the downhill again and removed the strain. If just driving around the city and normal strain, or even idling for hours it never climbs above half.
Here is the shopping list of things that were done:
1) Re-cored the original radiator at the time of the engine swap (ex 3F radiator) - and flow rate is good when tested recently (and we are doing some more detailed tests on it this week to make sure its not undersized for the diesel vs. petrol -- is this an issue that diesel needs more cooling than petrol??) No rust issues, or blockages we can see.
2) Tested the fan viscose coupling - seemed to be working well. But also serviced it with new silicone oil. Plus, tested her with a known working fan with a bigger diameter off another cruiser... still overheating. Also tried with the Shroud removed just in case that was the issue, but no assistance.
3) Replaced the Thermostat... I did find a number of holes drilled in the old thermostat (pointing me to think this is not the first time this engine has had overheating issues). Replacement is OEM from Toyota, and the parts guy said it was tested at the factory before they dispatched it to me. (We have not tried running the car with no thermostat at all... but the holes drilled in the old one - see pic below - make me think its not going to solve this issue)
4) Radiator Pipes are all newish and in good condition with no buildup or blockages.
5) Checked the water pump (metal blades) and all seems to be working appropriately and its definitely circulating
After doing all of this...
6) finally removed the head... there was a leak in the head gasket (see images below)... so we skimmed the head to get it smooth at an engineering shop and put the head back on with a thick gasket.
7) Sent the cruiser in to an Injector Pump specialist to check the timing was all good, and we were not overfueling. He did retard the timing some what, but the same issue remains.
I hoped no. 6 was the final step, but alas she is still overheating on sustained up hill drives at high revs... The car starts first time on a dime, and runs smoothly.
Anything I am missing - please help!! @roscoFJ73 you have been one of the most knowledgeable people I have encountered here around the 1HZ. Any ideas?
I attach some pics below for reference of the Thermostat removed, and the head off the engine
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-- this is not normal operating temperature for this engine is it? and this is a relatively short hill I am testing on
