730 Pistons In R

Estes

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So, I've been reading up on the R being Bored to 6 1/8" and putting in either 730 or 830 Pistons. Since I will most likely have to Bore my block, I believe this is the direction I'll be going.

What I've also seen is that you need to put the 730 or 830 injectors in it as well. Is this Absolutely necessary?? Or can you make it happen with the R Injectors? I'd like to know any success/failure stories of both if anyone has any.

Oh, and when using the 730/830 injectors... would you need the injector pump with it??
 
you will definitely want to talk to Albert from renaissance tractor. he will explain how you will need to match the injector spray
angles with the piston so the fuel will enter the top off the piston correctly. He is a great guy with boat loads of info.
 

Ha!! I've spoke to him once on something else. Yes, I will definitely be seeking his advice once I hit land again. Out here in the ocean when the wheels get to turning in my head, this forum is the only outlet I have.
 
IIRC early and later 720D had different pistons and injectors.

So make sure you match up everything for the same serial number ranges.
 
It's a shame no one makes overbore pistons for the R. Or at least I haven't been able to find any. Anyone had any luck with just re-ringing it? I can tell there is wear. But I'm not sure how much is considered too much. You can feel where the piston has worn down the cylinder wall.
 

New rings won't seal an egg shaped bore. If re-rung the end gap clearance needs to be set where the bore is the smallest diameter.
 
(quoted from post at 09:26:09 09/02/17)
New rings won't seal an egg shaped bore. If re-rung the end gap clearance needs to be set where the bore is the smallest diameter.

Understood. Does anyone know if Renaissance Tractors has an Email? I don't have facebook page (in case they have one of those). I'm in the Gulf also at the moment, so no Phone. Just wondering if I Email them and see what they have available.
 
There was an extensive article in one of the "TWO-CYLINDER" Magazines with pictures of a JD "R" that an individual in the USA had installed 730 JD Pistons and Injectors in a JD R....year of Magazine issue? According to the article, the HP on dynamo was impressive.

Bob..
 

I think I read the first page of that article. The rest was unavailable online. It was called, THE Super "R". The more I read on it, the more I like the idea of the "Halfbreed." Just learned that nickname today, lol.
 
the later 720 &730 used a keystone ring in the top grove the injs were the same on all 720s &730s but 2 different brands were used
 
Out of my league, but isn't the "R" a two main bearing crank and the 730, 830 have a center main?
CPeter
 
(quoted from post at 19:17:56 09/03/17) Out of my league, but isn't the "R" a two main bearing crank and the 730, 830 have a center main?
CPeter

Yessir, you are correct. But the Piston is the same profile... just a larger bore.
 
And the reason why B&D siad "For a while" as to its life. The crank is not strong enough to handle the extra cubes an the torque that they make and will break.
CPeter
 
(quoted from post at 20:39:18 09/04/17) And the reason why B&D siad "For a while" as to its life. The crank is not strong enough to handle the extra cubes an the torque that they make and will break.
CPeter

Well damn, I definitely don't want that. I wonder what the lifespan on this build would be? I'm really only going to be shredding with this tractor. No plowing, pulling or anything crazy. I've got a 15" Alamo Shredder, and that's it.
 

As long as you don't lug it down and make it pound along labouring it will probably be ok. The factory pto drive was not robust enough for stock R HP let 830HP levels.
 
(quoted from post at 04:23:46 09/05/17)
As long as you don't lug it down and make it pound along labouring it will probably be ok. The factory pto drive was not robust enough for stock R HP let 830HP levels.

There was an advert in Green Magazine from someone who is making R pistons. Presumably if they can make std they should be able to make oversize too? Dont have the info to hand im afraid.
 
(quoted from post at 06:23:46 09/05/17)
As long as you don't lug it down and make it pound along labouring it will probably be ok. The factory pto drive was not robust enough for stock R HP let 830HP levels.

Well, I may move forward with the bore then. My only worry with a bore and sleeve (to use the stock pistons) is that they would have trouble with the valve reliefs that are machined into the cylinders. Where I'm at, I've only got One machine shop, and they specialize in cars. Idk... guess I'll just take it up to them.

I'm finding out more and more with old tractors.... It's all hard, lol. No job is easy. It's definitely a labor of Love.
 
I doubt they have equipment big enough to handle it if they do cars.
You Do NOT want an R for PTO work as they have weak PTO's ! as they run off the fanshaft gears.
 

Ship the block, head , injectors and pumps to Renaissance Tractor. Everything will come back properly matched and ready to bolt together . Peace of mind can be purchased for a reasonable sum.
 
(quoted from post at 19:49:59 09/05/17)
Ship the block, head , injectors and pumps to Renaissance Tractor. Everything will come back properly matched and ready to bolt together . Peace of mind can be purchased for a reasonable sum.

I think that's the best option. I'll be calling them once I hit land for further discussion. Thanks for all the help so far.
 

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