Boxing in the rods

[Agco Avenger]

I am wanting to "box" a set of Farmall M rods to be used in a big bore Moline engine. I don't think the M rods are strong enough as they are, so I am wanting to weld a strip of some kind of high strength steel up each open side of the rod to make it stiffer without adding too much weight. Has anyone had experience doing this???
Avenger

 

[Anonymous-0]

you know i understand and have used verry punny rods before but i have never had one fail . i had one one time that was sightly bent but the rod juornal it was attached to was twisted into.

 

[SingleFrontWheel]

Why does everyone try to save dimes by spending quarters? No way I'd ever put an M rod in a Moline, boxed in, heat treated, cryo-ed or anything. By the time you do the work, and all the other stuff associated, spend the rest and do it right, if for no reason more, for peace of mind..

And YES, I am having a set of rods welded RIGHT NOW for a relatively mild AC project, so I am not being hypocritical..now that I have had the time to re-reason it, I would have at least gotten a quote on custom ones for probably $300 more...I dont know about you, but in a $4000 motor, $300 ain't Sh*T

 

[Mike N Mo]

I don't know if what you're planning will work, just be aware that the rods will warp when you weld them. Consider ther cost of having them straightened unless you're equipped to do it yourself. Mike

 

[Anonymous-0]

single front wheel be carefull you get called a person who throws money at builds . however i do agree . if it takes welding on them then it takes straightening them and if the dont go back through a hardening procees they will continually bend. but to some a thousand dollars a hundred dollars a time is more frugal than 1000 at one time.

 

[Anonymous-0]

I built jigs to hold em. The jig holds them well, once welded, I put em in a box of sand to cool. Takes me 20 hours each rod to make sure they are straight. There is more to it than butting them up and weldin.

This one is going into a 130hp M.
No, its not running the stock rod bolts, too weak! Chad

 

[Anonymous-0]

(quoted from post at 15:04:06 12/28/09) I built jigs to hold em. The jig holds them well, once welded, I put em in a box of sand to cool. Takes me 20 hours each rod to make sure they are straight. There is more to it than butting them up and weldin.

This one is going into a 130hp M.
No, its not running the stock rod bolts, too weak! Chad

WOW thats $600 a rod just in hours of labor.

 

[Josh Blackburn]

You guys act like a 8 inch welded rods are a big deal at 30 hp each one...We weld rods in our deeres ourselve and have easily 50 hp a rod that issomewhere around 15 inches long, Box your rods in and weld inch by inch on each side to keep them from warping they will be fine.

 

[SingleFrontWheel]

I know, Josh....BUT..its a DEERE..

They have ...

MUCH larger rod beams

MUCH less RPM

Fairly "low" compression..

and

(I am getting a little out of my realm..but)

A more generous rod angle.

It not the welding that scares me as much, its the rod angle tearing on the weld.
My rod ratio is something like 1.85 : 1 or so..thats the only reason I am going with this option.

ML..I AM a guy that throws money at a build, when I cant do it as well myself, or know it will be done right. Thats just common sense..

 

[Anonymous-0]

7 inch stroke seen here in an IH application. See that little clearence spot?

8 spots, simular to that, your done.

Anyways,,,

If your running offset bores, and rod journals still centered, super high cyl pressures, and high rpm, welded rods have short life written all over it.

This one is lined up off the stock bore spacing, so when it fires, it comes down right in the middle of the wrist pin, centered if you will call it, from the piston bore center to the rod journal center, or within .100 from that line.

This one figured out to be 12.5 to 1. Compression ratio, I am not too far off from trying to break it in two or twenty pieces to know if we can actually say,,,,,,,, yeah, we can weld em up and do just fine. So far, it spins nice, with only one visit to the press to straighten. Cant wait to run it warmed up,,, pul the pan off, and check sideplay, and bearing surfaces. ChadS

 

[Anonymous-0]

in the pic looks like the side clearance needs a little belt sander adjustment of coarse its hard to see .020 exact from a pic.

 

[Anonymous-0]

chad how long is the rod.

 

[Anonymous-0]

Anywhere from 7 to 10.5 long. Stock M-450 is 10. ChadS