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Discussion Starter #1
I am learning as I go here.

Quick version:

LGT 16
Do I need to file/sand big end of connecting rod to move freely on crank? I've torqued rod bolts and now the crank will not budge.

Long Version:

I am on my second - soon to be third I believe - connecting rod in my Ford LGT16. The first rod I replaced - I torqued the replacement rod on the crankshaft with the crankshaft in a vise and only then wondered how I was going to get the assembly in the engine. 馃榿

So after taking it all apart and re-torquing bolts and reassembly - engine ran from my barn to about half way down the drive. Those 9 seconds were very proud seconds. The instructions were to NOT torque and re-torque rod bolts so I am guessing that was the cause of the second rod shattering.

Having 'fixed' this once I figured I could learn on my mistakes and try another rod. This is where I am now. Having done everything 'correctly' this time - I am now wondering why the rod/piston will not move.

I did have to slightly file down the piston end of the rod for it fit in the old piston and move freely but I did not think to check the big end/crank end.

So I am basically back to where I started a year ago. While I have the momentum with this project I thought I'd ask around. I found many posts with connecting rod related questions but not this one.

Thanks,

jw
 

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NEVER file a rod for fit. If it doesn't fit right when torqued you need a new or reground crank and connecting rod. If it was the right sized parts it would turn easily. Roger
 

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Discussion Starter #3
NEVER file a rod for fit. If it doesn't fit right when torqued you need a new or reground crank and connecting rod. If it was the right sized parts it would turn easily. Roger
Thanks Roger.

That is what I was afraid of. Not sure I'll continue putting money in to this but I appreciate the reply.
 

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I agree that you should not file or sand it down....but if anything the crank would be worn down and the rod would be loose...are you sure you have the correct rod?
 

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Discussion Starter #5
Good call Mark, thanks.

I cannot find where I purchased the last rod from in my email - it has been sitting for quite some time - but after looking at messicks I know I did not spend 150+ for it. I want to say it came from isavetr.. But now looking at those pictures and the one I have - they look different. These sell for 40. I would have paid that.

Might gamble one last time for 40.

It is a Kohler K341AQS

Yea I'll gamble.

If this doesn't work... anyone looking to buy a gently used LGT?!

Thanks again all.
 

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is there an oil bearing in between the rod crank?... if so - did you get the right bearing?
 

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I agree that you should not file or sand it down....but if anything the crank would be worn down and the rod would be loose...are you sure you have the correct rod?
I am learning as I go here.

Quick version:

LGT 16
Do I need to file/sand big end of connecting rod to move freely on crank? I've torqued rod bolts and now the crank will not budge.

Long Version:

I am on my second - soon to be third I believe - connecting rod in my Ford LGT16. The first rod I replaced - I torqued the replacement rod on the crankshaft with the crankshaft in a vise and only then wondered how I was going to get the assembly in the engine. 馃榿

So after taking it all apart and re-torquing bolts and reassembly - engine ran from my barn to about half way down the drive. Those 9 seconds were very proud seconds. The instructions were to NOT torque and re-torque rod bolts so I am guessing that was the cause of the second rod shattering.

Having 'fixed' this once I figured I could learn on my mistakes and try another rod. This is where I am now. Having done everything 'correctly' this time - I am now wondering why the rod/piston will not move.

I did have to slightly file down the piston end of the rod for it fit in the old piston and move freely but I did not think to check the big end/crank end.

So I am basically back to where I started a year ago. While I have the momentum with this project I thought I'd ask around. I found many posts with connecting rod related questions but not this one.

Thanks,

jw
You do not describe the first failure except to imply it was catastrophic, and required at least a new rod. Could the first failure have bent the crank? This would bind the piston in the cylinder and not allow the crank to rotate.
 

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Discussion Starter #8
I do not think there was an oil bearing - all parts that came out of the first clean out seemed to be aluminum and part of the original rod.

Bo - I do not believe the crank is damaged. There where a few minor scuffs on the crank where the connecting rod attaches to the crank (do not know term) but I ever so lightly wore those down to the point where I believe they would not be an issue.

I've yet another rod ordered from isavetractors and will see what happens. I'm already way too deep in to this thing but what else do I have to do during quarantine? Plenty.

And I forgot all about the cracked magnet on the flywheel - oh joy.

Thanks for the comments and questions. Every bit helps.
 

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I would do the same as you did earlier. Assemble the rod and crack outside the engine. If it is tight then, there is no sense going any further til you figure out the issue.
 

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Discussion Starter #10
Thanks. I just wont torque them down this time! Great challenge but frustrating. Dig your quote.
 

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Buy plastigage. That will let you know the clearance.
Some bearings are available standard or sized depending on how it was machined, and it all has to be exactly right affecting performance, oil pressure, longevity.

Sent from my SM-S320VL using Tapatalk
 

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I am curious about this tractor. Is it a diesel? According to Tractordata.com the Ford LGT16 only came equipped with a diesel engine. This information may not be accurate, so I am curious. If it is not a diesel, are you absolutely sure you are ordering parts for the right motor?
 

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I am curious about this tractor. Is it a diesel? According to Tractordata.com the Ford LGT16 only came equipped with a diesel engine. This information may not be accurate, so I am curious. If it is not a diesel, are you absolutely sure you are ordering parts for the right motor?
He gave the engine info. Kohler K341AQS. Its a 16HP gas. Should be stamped right into the right side engine cover.
 

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Discussion Starter #16
You are correct Ariens - gas. I've never heard of plastigage but will search in a moment.

And I did convert inch pounds to foot - believe it came out to ~ 20.5 or ~ 21.5 ft lbs. I have it written down somewhere.

Does anyone have any tips on finding flywheel ferrite magnets? I see a few posted on ebay but I am always weary of ebay items.

Thanks again.
 

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Well there is a problem. OP says he is not going to torque the rod bolts when trying the rod to crank fit. That will do no good unless he is getting a .010 under size rod for a standard crank then it would show but otherwise with plastigage or just a trial fit rod bolts need to be torqued. And I would use an inch lb torque wrench rather than convert. Don't know about that engine but I have gotten Kohler Service Manuals free over the Internet, suggest getting one. Also I question condition of rod throw especially after throwing two rods. By the way, crankshaft will not be bent. Sand piston end of rod to fit? Something bad wrong here.
Walt Conner
 

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Discussion Starter #18
Thanks Walt.

I have the manual printed out but the instructions with that came with 2 rods said NOT to torque rod bolts prior to final installation. The way I understand this is that, once torqued, they 'seat' themselves in the aluminum and by unthreading them you are essentially jeopardizing the bolt integrity. I could be completely wrong.

Jeff
 

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What I would do....If that is a new rod, I would take it to a machine shop and have them measured. It looks to me that you have an undersized rod and the crank hasn't been ground undersize. Grinding the crank to the rod size is the thing to do...it's not expensive
 

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Discussion Starter #20
Thanks Poncho. I am in a holding pattern until the new rod arrives. Best case here - I'll have a replacement rod on hand.
 
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