12HT/2H crank question (1 Viewer)

[CenTXFJ60]

I tore down this 12HT that belongs to a friend which spun the #1&6 rod bearing. The machine shop states it’s not advisable to grind it as #6 is pretty torn up. Pic is of #6. I’ve done some research via google and here on MUD and there’s been some discussions around these two cranks being interchangeable even though they have different part #’s. Via google I’ve seen harmonic balancers marketed for both the 2h & 12HT. My question is has anyone actually put a 2H crank into a 12HT and if so, we’re any modifications required? My understanding is the bearings share the same part #. Thank you. Jimmy

 

[troopie]

I've had 2H and 12HT cranks side by side. They would definately swap out, but the 12HT crank has more meat in some areas.
Not all, but some off the journals have a wider casting. Not sure if my explanation makes sense.

 

[CenTXFJ60]

Thank you for your reply. Do you happen to have a 2h crank out of a motor? Something I’d like to get would be measurements to compare it to the 12HT crank. And I assume you’re referencing the lobes as having more meat. I’m far from a mechanic, but if that’s the case I wonder if the 2H crank would perform in the 12HT block the same as a 12HT crank. Also curious if the harmonic balancer can be swapped between the two cranks. Thanks again. Jimmy

 

[troopie]

Unfortunately i have nothing left out of a 2H of 12HT.

The harmonic balancer should swap over. The crank itself should also perform in a 12HT, the only thing i would be worried about is breaking the crank. That's what happenend to mine years ago. It broke in a spot with more meat then a 2H crank. Now i have to say i was running 37's, more boost and more fuel.
In stock form it would probably hold up, but Toyota didn't redesign the crank for no reason.

If there is no way for you to get your hands on a 12HT crank, i would swap in a 2H crank and be gentle with it. Keep the injection timing on the conservative side. In the mean time keep your eyes open for a 12HT crank. Those are not easy to find, so it might be a while.

Maybe @joekatana could help you out?

 

[ToyotaMatt]

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Jimmy i have this if it can help ?

 

[sodafeld1]

interesting stuff, for the effort and cost , probably better to get/find the 12ht crank and not tippy toe.

 

[wedgetail]

can you get your original 12h-t crank built up with metal spray and machined back?

 

[sodafeld1]

can you get your original 12h-t crank built up with metal spray and machined back?

that would be a mission!

 

[wedgetail]

that would be a mission!

Yes it would, but it could be years and or
thousands to get an original usable 12H-T crank. Getting his done up would give him a definite option

 

[sodafeld1]

yeah true, parts would be getting rare indeed. Be interested in a documented build up and grind of a crank, and how much it costs. Anything is possible.

There is some pakistani youtubbies of semi primitive head repairs which makes things look doable. With a modern workshop it could definitely be done.
I have 4 x 2h crank spares kicking around.. Was quoted $1500 to freight one melbourne to texas, I said he may as well fly here.

Shame they stopped making the 12ht.

Elderly neighbour has a 12ht with 300ks but he is happy to sit on it. He just ticks it over to the tip and back every now and then, the auto trans is buggered on it.

Brain numbing 38c here.