83' 3B possibly cracked head?

[DieselCruiser81]

A few years ago I had the head on my 3B welded up and Im thinking it is cracked again. When I am traveling at 60+ MPH the temp gets close to overheating and my radiator keeps overflowing into my overflow. I'm thinking combustion gas is getting into the radiator and causing it to overflow, any thoughts?
Thanks

 

[CRZR45]

Head gasket?

 

[DieselCruiser81]

It could be the head gasket but I'm thinking the head since I've already had to repair it.

 

[brownbear]

certainly it sounds that way. But that's the big work, and you should do some trouble shooting first.

Pressure test the coolant system.

I had overheating like you mention above and it was the strength ratio of my coolant was too strong and did not have enough water in it. Oddly it would overheat, then I increased the water and it would handle the heat dissipation better.

 

[Katsarata]

Do a gas test on your overflow bottle that'll tell you if you have gas in your water, I think it would probably get hot at 60 mph + anyway. Do the simple stuff first make sure your fan's working properly flush your rad get coolant ratio right.

 

[RufusTheDufus]

Something like this will help. Just be sure to buy one that will detect diesel combustion gases. Not all of these test kits will detect diesel.

 

[DieselCruiser81]

Thanks for the help. I will get that tester and post the results.

 

[DieselCruiser81]

Rufus,
I bought the test kit you recommended and it tested negative for combustion gasses. Can you walk me through the testing procedure just so I can make sure I did it correctly?
Thanks

 

[RufusTheDufus]

I can dig out my test kit and see what the instructions are for my kit. I'm not sure that I have the same one I linked to above. Doesn't yours have instructions?

Looks like the instructions for that kit I linked to are here

 

[DieselCruiser81]

It has instructions that I followed It just didn't leave me feeling like it was a good test. The instructions did not indicate if the engine should be running or not. I ran it and brought it up to temperature before the test. I guess the combustion gases just collect sit above the antifreeze? How do they not escape as soon as you take the cap off?
Thanks

 

[RufusTheDufus]

I think the test fluid reacts to the presence of carbon monoxide but I'm not sure. Diesel combustion produces a different combination of exhaust gasses which is why the instructions say that the fluid will turn green instead of yellow and it requires more pumping of the vacuum bulb for diesels.

If your leak only happens under load to the point that it's pushing coolant into your overflow tank you could test the gases at the overflow. Intermittent problems are difficult to diagnose.

I had similar problems in my H when I put a turbo on it. I could never quite figure out why the cooling system would start pushing into the overflow if I drove 65MPH. If I stayed at 55 it worked fine with no overheating. I drove it like that over 12,000 miles. I eventually gave up on it and yanked the engine after I overheated it real good on the highway one day.

 

[Dieseler]

My experience if you pull off the rad cap and run the engine let it heat up and even rev it you will usually see tiny air bubbles escaping this is a sure sign of a serious crack or blown head gasket.

 

[gerg]

When I was checking for a suspected HG leak years ago I ran a clear tube from the side of the rad cap that goes to the overflow and instead ran it to a part filled pop bottle and straped it in the seat beside me. The clear tube went to the bottom and I could easily tell when the gasket was leaking as the tube would bubble. So now there are obvious inherent risks with doing that like severe life altering full body burns and stuff, but it told me what I need to know. Only leaked under sustained heavy load.

 

[DieselCruiser81]

Dieseler,
I actually did that yesterday and I noticed tiny air bubbles rising up and I wasn't sure if that meant anything or not. The head was cracked when I bought it and I had it repaired so I'm leaning towards the head more than the head gasket.

Gerg,
Thanks for the info, my problem only arises under a sustained load also.

 

[DieselCruiser81]

Where is the best place to buy a new head and gasket? I have contacted engines Australia, are they the best people to go through?

 

[RufusTheDufus]

There are a few threads in the forum here that mention sources for an MLS head gasket for the 3B. I think Toyota may still even have them.

 

[OGBeno]

11115-58110 is the gasket part number. I have one available.

The head is no longer available from Toyota. Known good used that can be rebuilt or Engines Australia would be a decent choice.

 

[DieselCruiser81]

Any chance it could be the water pump causing all of this?

 

[DieselCruiser81]

So the head gasket was definately leaking possibly do to a warped head. I put a new gasket, head, head bolts and factory Toyota thermostat. I also checked the water pump and it was fine. It is not blowing coolant out anymore but it is wanting to get close to hot at highway speeds around 70. I am looking at putting a bigger radiator for more cooling capacity. Does anyone know of a 3 core aluminum radiator that will fit in the factory space and use the factory fan shroud?
Thanks

 

[RufusTheDufus]

Champion has a 4 core aluminum that fits in the factory space. You need to bend the bottom corners of the radiator support outward slightly for the 4 core to fit. I installed one in my Troopy. I had to make my own lower rad crossover pipe but that wasn't difficult.