Rolling my own 12HT /HJ60-62 (1 Viewer)

[Gengis]

Am I a thief or a sucker?
I picked this little baby up this morning. She lived in an abused Zimbabwe Coaster bus for the last few years and is now mine. Paid about $900 US or AUS

It is a non-runner and the PO claims that he had problems with the pulley spinning on the flywheel but the head was at the engineering when I first set eyes on her, so F**K knows whats really wrong. Got the starter and alt and AC compressor but no sign of a PS pump.

Turbo had a wobble but does seem to have touched, but definitely got some bad air at some stage.
Anyway folks, look forward to some pics and lots of questions and please chime in at any time. My goal is to get her up and ready to go into a FJ wagon.

 

[Gengis]

OK , So the Coaster pulley caters for no less than 5 belts. So if that bolt is not nice and tight that baby is going to be a trouble spot. The Law of the Lever gurarantes this.
So checking out the end of the crank is the first step. threads look tired but OK. The journal which receives the pulley feel OK but measures 35mm in diameter.
I don't find this measurement in the good book, so if any kind soul has a 2h or 12ht crank laying around, then please measure this up for me.
Obviously then, a HJ61 pulley is in my near future, I can just feel it.
New one's still available???
Regards G

 

[ozwallaby]

I'll be at my parts car tomorrow (in abt 15 hrs)... I know I have a 2h crank out of a motor on the floor there so will measure it for you if I remember my verniers....

You say the PO says he had a pully spinning on the flywheel... think he means pully spinning on the crankshaft.....

 

[Gengis]

Cheers OZ much appreciated

What the hell did they drive with 5 belts?? I guess the regular HJ pulley looks a little different??
My 22mm socket slipped on the bolt and I don't have the 40+ socket, so out came the welder, I think the heat helped a bit as well.
I did a proper measurement on the shaft again, and it's as close to 35mm as dammit. the pully is only marginally bigger but you can see the wobble damage in my first thread.
Just a few household chores to clear, and we are A for away on this baby
Yes, pulleys spin on cranks, not flywheels, my typo.
G

 

[ozwallaby]

Sorry man, had completely forgotten to get that measurement for you, hopefully someone else will be able to help out... once again sorry...

 

[Gengis]

No problem, when you get a moment.
35mm just seems a little un Japanese if you get my drift.
The shaft however, looks unmolested. It's surprising how much wobble a few microns can produce.
I'm looking out for an HJ61 pulley locally anyway, and I'll take it from there.

Regarding the pics below, I take it that the black arrow is a heater return and the red, a heater out? OK so on this engine there is another return at the end of the pipe and another outlet at the other end of the head. Normal?? Two heaters in a bus??
Is at least the turbo return (yellow arrow) in the correct place?

 

[Lasse]

Your hot water pipes look different on your engine than on an engine delivered in a cruiser. Your charge pipe also differer.

You are right in your assumption. Cold spec cruisers have two heaters with there each water outlet from the top sharing the same return.
Surely there was more than one heater in the bus?

I am pretty sure you can plug the most rear outlet without creating circulation and cooling problem, but not entirely sure.

 

[roscoFJ73]

Yes ,2 heaters for sure. Thats a good buy,it would cost you 3x that for something that needs a rebuild in OZ. Ive heard of the 12HT coaster bus ,but never seen anyone with an engine out of one on this forum.

Is it a 12v or 24v? How many klms?

 

[roscoFJ73]

Cheers OZ much appreciated

View attachment 909564
What the hell did they drive with 5 belts?? I guess the regular HJ pulley looks a little different??

Parts diagram only shows 3 belts,maybe 4 if something was using 2 belts. Its possible they had something extra running off the crank.

 

[Gengis]

What the hell did they drive with 5 belts??

Ok if we split hairs here, I guess it's only 3 belts, a single and 2x doubles. Still too big heavy and long for the stump on the crank shaft end IMHO.

OK so I guess Toyota wanted to keep their passengers warm. I'll hang on to this stuff, but I don't see much of it going back on the engine.

Also, does this look like the wagons (HJ61) alternator?? The label has faded but it looks up to the task whether 12 or 24. More sleuthing to be done.

 

[blis]

Looks nothing like the alternator on my 24v hj61... Well, besides looking like alternator... different vacuum pump and the bottom of alternator looks odd...

 

[Lasse]

Looks a little different. But guess yours will do the job just fine

Went out and took some pictures for you to compare.




Sorry, no readable part number here either. It is 24v.



Also took the liberty to take some pictures of the heater hose and tubes routing.










Turbo water cooling return:



Let me know if you need any other pictures of an stock HJ61.

 

[Gengis]

Cheers Lasse
This will help piece it all together.
I guess that whatever way one hooks up the heater, just get the turbo return right as well.
G

 

[Lasse]

No problem, always a good feeling being helpful

I back traced the part number on the alternator; 27020-68150. It gives me 24v 40A internal regulator.
The 84 ending means it is remanufactured by Toyota from an used core unit.

If yours are a 24v unit, it properly is a 55A unit. Seems like there also was a 85A alternator available, if you are lucky you have one of those.
Is it possible to see a part of the part number?

Don't remember exactly, but do believe turbo cooling water supply comes out of the block somewhere, can look at it tomorrow if you like.

Could you measure the pulley grove width? Looks like it might be 1x 17mm and 4x 13mm?

 

[Gengis]

OK so the head is off, and like the PO said it does seem to have just returned from the shop. It still oozes rebuild grease has new wealsh plugs and a great big OK painted on it. I will still pull the valves and check out the seats and guides.

The rockers look OK for the mileage but I may look into hardening and grinding

Sh*&^$ T, its a 24 volt system- More money on a 12 vswap out. still cheaper than converting a 12 volt wagon to 24V??

@ Lasse concerning the pulley dimentions.
The two closest to the engine are 160mm and take a 10mm belt the next two are 196mm dia also taking 10mm belts and the 5th bolt-on pulley is 165dia taking a 13mm belt. Not sure about the belt dimentions, but the grooves at their widest are 10 and 13 mm respectively.

 

[Lasse]

If not cheaper, a lot easier!

I think a 24v system is far superior in most aspects except for accessories.

You will need a new alternator, its the easiest route.
I do believe it will work to just change the regulator, but other components in the alternator are designed for 24v and it will run at low efficiency and producing low current.
You will need a new starter, alternator/regulator, 12v pneumatic valve for shut down and a new 12v glowscreen. (You might get away running the 24v glowscreen on 12v)
If you are changing the truck over from 12v to 24v you will need to change about everything. Every little relay and control box and I am not sure it the wire harness is the same either.

That are some small belt grooves, my 12H-T runs 17mm belts on everything.

 

[Gengis]

OK, so to boreing matters
The PO has re-sleeved this baby, and the sleeve condition does not look wonderful.
They are thin steel, about 2mm thick and 95 in OD.
What are my options?
What is the OD of the sleeve available from EA.
I believe cast iron is best for diesels? yes / no
Is cast iron sleeve stock available in around 91mm id 96mm od?
I guess that if all was well, I would not be able to do my little feeler gauge trick?

Your thoughts please
regards
G

 

[roscoFJ73]

I believe cast iron is best for diesels? yes / no

I would just go with what ever Toyota used,plenty of 12HT getting around with 500000klms+

 

[Gengis]

Any one have experience with Arco pistons and liners??
They have a really nice deal for a complete set of 6 1st oversize pistons rings pins etc. about £300 US or AUS. ( does not include liners)

 

[Gengis]

I would just go with what ever Toyota used,plenty of 12HT getting around with 500000klms+

A bit late for that Ross, Toyota never used liners in this baby.

G