Coolant in crankcase HJ45

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Hi Mudders,

First thread start for me after using this amazing site for a couple of years now.

After owning a 80 and a 90 series (yup infected with the LC virus) i purchased a 1977 HJ45 LP KW a month ago, original 1H engine still in.

First thing i noticed was the coolant temperature was low when engine was running.
So opened up the thermostat housing and to my surprise there was no thermostat fitted at all.
Bought and fitted a new oem thermostat together with a oem radiator cap and coolant temperature went to normal operating temperature.

But now next problem, when engine running it started using coolant and blow mist out of the crank vent and oil filler cap, oil filler cap also became very sludgy(was clean before).
Also noticed a risen oil level after i ran the engine.

So i let the engine sit for a couple of days and pulled the oil drain plug, just as i expected a cup of coolant came out first before oil started to come out.

Does anyone have experience related to this specific problem and engine?
I thinking head gasket or maybe cilinder sleeves in block are leaking.
And because of increased pressure because a new thermostat and radiator cap were fitted, the coolant system is now showing its leaking badly.
Too bad PO did not mention this :(

Also before i mounted the thermostat and new radiator cap the engine was running just fine, only blowing smoke on startup after that it disapeared reasonably quick, even after running idle for a while and or revving no smoke appeared, which lead me to believe the engine was all good.

Any help and ideas are very appreciated.
 

pb4ugo

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I'm not familiar with the engine, but your discriptions and analysis are pretty correct. You need to do some testing to isolate what the problem may be. To start, do a compression test, and pressure test the cooling system, to try and find the problem. You are correct the new cap and t stat pressurized the cooling system. The PO probably knew there was a problem and did things to mask it. It could be a head gasket, cracked blk, cyldr sleeves or cracked head.
 
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Thanks for the reply much appreciated, dont know the oem compression specs as there is little info available on these engines, cant find a H engine FSM either. If anyone knows please let me know

Pressure testing the cooling system is something i can do, however i know allready that there is a internal leak, and I think its not possible to remove the head and pressurize the system? Or would opening the oil pan and look for leaks inside the crankcase, and pressurize the cooling system at the same time be the way to go?
At what pressure should i test the cooling system?

Would cracks in the head or block that leads to this problem be obviously visible?

Also i put a new radiator cap on because the old radiator cap was missing the rubber to actually seal the spring loaded part of the cap to the radiator, which obviously lead the cooling system not being able to pressurize.
If i only noticed it that earlier :(

Also are these engines worth the trouble, time and money to rebuild? Or would a different engine be the way to go?
 
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Thanks for the reply much appreciated, dont know the oem compression specs as there is little info available on these engines, cant find a H engine FSM either. If anyone knows please let me know

Pressure testing the cooling system is something i can do, however i know allready that there is a internal leak, and I think its not possible to remove the head and pressurize the system? Or would opening the oil pan and look for leaks inside the crankcase, and pressurize the cooling system at the same time be the way to go?
At what pressure should i test the cooling system?

Would cracks in the head or block that leads to this problem be obviously visible?

Also i put a new radiator cap on because the old radiator cap was missing the rubber to actually seal the spring loaded part of the cap to the radiator, which obviously lead the cooling system not being able to pressurize.
If i only noticed it that earlier :(

Also are these engines worth the trouble, time and money to rebuild? Or would a different engine be the way to go?

Your question on whether or not that engine is worth time and money to rebuild is one only you can answer. I used to have a 2H and it was an absoloute slug. I cant imagine how slow a 1H must be. But if you want to keep it original/period correct the 1H is the way to go.
Are you in the USA or Australia?? America doesnt have the same love for diseals as Australia does so I'm not sure how parts availability is over there for an old 1H. The American guys would be better placed to answer that.
 
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He’s in The Netherlands
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H motor has dry liners and run pre chambers. I still have two running here in a 45's (one with turbo fitted.)
They're notorious for cracking per chambers and heads. The block is usually quite durable.
I'm finding them a bit harder to get parts for than compared to 2H. 2H has same overheating issues but lot more linear torque curve than the H.

Depends what you use the vehicle for? Dropping a 2H in place of the H is a little bit of stuffing around far as bell housing, radiator and gearbox mounts.
2H will be much easier to get parts for but still a gutless pig on the road.
 
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Thanks a lot guys, i'm from the Netherlands indeed, not as easy to get parts here compared to Oz or America.
Still i found 2 quite cheap 2H motors on the internet, so i dont think it it very economical to rebuild this 1H(cant find anything for this motor).
A pity because i think the engine still had plenty of life in it apart from te leak issue, but i will open the head at a later stage and hopefully see what is going on.

45 will be used as (eventually hopefully in a couple of years ;) ) a daily driver, work around the farm, travel, camping and 4x4 vehicle, no showpony but should be decent looking and no rust.

Not sure if want to go through the trouble converting it to a 2H(or is it so simple?), or spend more time and money and do it right once, converting it to 80 series HDJ with gearbox.
Does anyone know if a 45 transfercase fits on a h150/h151 gearbox?
Would very much like to keep the pto and winch.
It would have to wait to get funds but got plenty of bodywork and other stuff to work on the 45.
 
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Parts for a 2H should be no drama. Toyota was putting them in 70 series Landcruisers into the 1990's. But like I said earlier, it will still be a slug. If your driving around in a 45 though, part of the experiance is putting along excruciatingly slow!

The 1HDT would be better in every single way, but a much more involved engine swap and would get rid of some of the character in my opinion.
 
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Might not be much wrong with that H motor!
Before pulling it down, remove the rocker cover and check coolant is not leaking out on top of the head as have five little expansion/freeze plugs in there.

These can be replaced without removing the head or manifolds.
 

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