Torquing rod bolts how do I line up the cotter pin
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Category: Allis Chalmers
Forum Name: Farm Equipment
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Topic: Torquing rod bolts how do I line up the cotter pin
Posted By: TX fanatic
Subject: Torquing rod bolts how do I line up the cotter pin
Date Posted: 05 Sep 2012 at 7:21pm
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I am in process of putting my C's motor back together. I have got to he point of installing the pistons and here's my question Out of the 8 rod nuts only one of them (torqued to spec) has lined up with the cotter pin hole! Do I over tighten it, or back off until it lines up, or do I use shims (washers) under the nut? Thanks Steve
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Replies:
Posted By: MACK
Date Posted: 05 Sep 2012 at 10:00pm
| Throw the cotter pins in the trash can. That is old knowledge. MACK |
Posted By: dave63
Date Posted: 06 Sep 2012 at 6:16am
explain yourself? I have a C engine tore down now that has two rod cap nuts ,the rod cap in the pan and the rod went through the side of the block becouse the last person that was in there did not put cotter pin through the nuts.
To answer the question the service manual calls for 35 ft on the rod nuts the last one i did i had to put 40 on them to lie up the pin holes and it turns over nice. It is not finished so i don't know if there will be a problem or not but.
BTW the service manual says make shure the cotter pins are snug becouse they will wear out if they can move. ------------- The universal answer to all questions is yes, how much do you want to spend? |
MACK wrote:Posted By: DonDittmar
Date Posted: 06 Sep 2012 at 6:23am
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I always torque to spec, then tighten till the hole lines up, if needed. ------------- Experience is a fancy name for past mistakes. "Great moments are born from great opportunity" 1968 D15D,1962 D19D Also 1965 Cub Loboy and 1958 JD 720 Diesel Pony Start |
Posted By: Lonn
Date Posted: 06 Sep 2012 at 6:26am
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Replace nuts with new type nuts that are the locking type used in newer engines. Some call them aircraft nuts. Kinda cone shaped. ------------- -- --- .... .- -- -- .- -.. / .-- .- ... / .- / -- ..- .-. -.. . .-. .. -. --. / -.-. .... .. .-.. -.. / .-. .- .--. .. ... - Wink I am a Russian Bot |
Posted By: Lonn
Date Posted: 06 Sep 2012 at 6:30am
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This is what they look like. http://apex-inc.biz/an363-524.jpg" rel="nofollow - http://apex-inc.biz/an363-524.jpg ------------- -- --- .... .- -- -- .- -.. / .-- .- ... / .- / -- ..- .-. -.. . .-. .. -. --. / -.-. .... .. .-.. -.. / .-. .- .--. .. ... - Wink I am a Russian Bot |
Posted By: Amos
Date Posted: 06 Sep 2012 at 7:17am
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Clean nut and rod bolt as clean as you can get them and use red loctite.
Don't trust lock nuts, they can work loose.
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Posted By: Gatz in NE
Date Posted: 06 Sep 2012 at 7:57am
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Posted By: MACK
Date Posted: 06 Sep 2012 at 8:02am
| If they are properly torqued they will stay tight. How many nuts have you ever saw loosen against cotter pin? In my 50+ years of mechanic work I have never saw one. MACK |
Posted By: 7060
Date Posted: 06 Sep 2012 at 8:27am
| I agree. I don't think they would come loose, but for insurance you could put a drop of red locktite on them. That engine only turns about 1500, unlike a puller or something. |
Posted By: WC7610
Date Posted: 06 Sep 2012 at 9:24pm
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I've never seen one loose against the pin either, but it would be my luck the one I didn't put a pin in would come loose. Seems like a rather simple task to complete compared to the whole engine overhaul. Good luck! ------------- Thanks Most Bad Government has grown out of Too Much Government- Thomas Jefferson |
Posted By: TX fanatic
Date Posted: 07 Sep 2012 at 10:45am
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Thanks for all of the suggestions. I haven't decided for sure what I'm going to do. I did give it some thought tho. The factory must have tightened or loosened them to fit the cotter pins because they most certainly did not line up every time. This is probably the route I'll go.
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Posted By: mdtractormechanic
Date Posted: 07 Sep 2012 at 10:48am
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As Don said, Torque to specs then tighten the castle nut to the first opening. This is the only method when using castle nuts for torque specific applications. And as Dave said, once you re-install a new pin back the nut off against the cotter pin to keep it from wearing from vibration. As for 'old knowledge' (by this I'm guessing it means old technology), does that imply that there is something better? What about the wheel? If something works and works well what's the point in modifying it. ------------- Joe's 1939 Model WC, 1940 Model RC, 1944 & 1950 Model C's, B-125 PU |
Posted By: Dick L
Date Posted: 07 Sep 2012 at 6:39pm
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Not old knowledge but but standard practice on old tractors and old cars rod bolts with cotter keys before tag was a pup. Bring the torque up to spec and tighten just enough more to insert the cotter key. On this engine you would bring it up to 35 pounds torque and put the cotter key in at slightly over 35 pounds. That will put it between 35 and 40 pounds of torque.
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