What is the Name of the Tool to Remove this Nut?

[Wotname]

Originally Posted by Jannie Radiance

If pulley turns clockwise when you look at it from the front, Then the thread may be lefthand.

Ya must've missed posts #7, #71 & #72...

[skipgundlach]

Originally Posted by Wotname

Ya must've missed posts #7, #71 & #72...

Not to mention #75

[Wotname]

Originally Posted by skipgundlach

Not to mention #75

Yeah but you post quicker than me

[skipgundlach]

Originally Posted by Wotname

Yeah but you post quicker than me

[Jannie Radiance]

Originally Posted by Wotname

Yeah but you post quicker than me

I am in Africa.....With copper wire and and dial - up modem, we have only received post 3 up till now.

[Cadence]

Originally Posted by Wotname

IT'S APART

The special custom tool required turned out to be a combination of a bench vice, a 24" Stilson, a 15" Crescent, a 18" Crescent, 4' of water pipe and some chain and turnbuckle.

Job held in the vice, the Stilson was used to hold the pulley and shaft. The chain and turnbuckle kept the Stilison from moving. One Crescent to grip the nut and the other to turn the first Crescent with extra leverage supplied by the water pipe.

Took a surprising amount effort to get it to turn.

Thanks for the update and glad you got it. You had gotten an amazing no. of sane suggestions.

Re: amount of effort. Is it possible someone had previously had it apart and reassembled it using the old school method of a center punch to lock it from backing off?

[Jim Cate]

Well done, Wottie! Quite an assortment of implements there, but couldn't you have hitched one of the nags up for power and not needed the four foot pipe?

Keep up the good work!

Jim

[Wotname]

Originally Posted by Cadence

Thanks for the update and glad you got it. You had gotten an amazing no. of sane suggestions.

Re: amount of effort. Is it possible someone had previously had it apart and reassembled it using the old school method of a center punch to lock it from backing off?

Possibly but I can't see any evidence of such. In fact, the rest of the engine has come apart surprising easily and it looks like this is the first time it has ever been apart - which is a good thing .

Best I can tell it is now about 40 years old. I thought getting the liner out might have problematic but not so; especially as it is raw water cooled. I simply removed the anode and thermostat, filled the waterways with 16% hydrochloric (muriatic) acid for about 30 minutes, removed it, neutralised with bicarb and used a press to pop out the liner.

Yes, you are right, the suggestions kindly given have been great!

[Wotname]

Originally Posted by Jim Cate

Well done, Wottie! Quite an assortment of implements there, but couldn't you have hitched one of the nags up for power and not needed the four foot pipe?

Keep up the good work!

Jim

Perhaps Jim but the water pipe doesn't mess in the shed

[DsquareD]

Hi,

I'm glad you finally got that stubborn nut removed. I'm also glad you decided to reassemble it with the original nut.

I used to manage a machine shop, although I'm not a machinist. I have processed many orders for nuts like this to original equipment manufacturers. I don't know why they wanted them, as they were much more expensive than an off the shelf variety, but the engineers who designed them had a very specific purpose in mind. For whatever reason, they felt it was the best solution and must have had some sort of failure with a standard nut in the past and thus prescribed this one. I would not second guess the engineers on this one.

Perhaps an engineer or machine designer could jump in with an explanation.

[captlloyd]

Originally Posted by DsquareD

Hi,

I'm glad you finally got that stubborn nut removed. I'm also glad you decided to reassemble it with the original nut.

I used to manage a machine shop, although I'm not a machinist. I have processed many orders for nuts like this to original equipment manufacturers. I don't know why they wanted them, as they were much more expensive than an off the shelf variety, but the engineers who designed them had a very specific purpose in mind. For whatever reason, they felt it was the best solution and must have had some sort of failure with a standard nut in the past and thus prescribed this one. I would not second guess the engineers on this one.

Perhaps an engineer or machine designer could jump in with an explanation.

Perhaps that nut could have served as some sort of drive takeoff? At any rate, great job Whatname! Victory!

[Wotname]

Originally Posted by DsquareD

Hi,

I'm glad you finally got that stubborn nut removed. I'm also glad you decided to reassemble it with the original nut.

I used to manage a machine shop, although I'm not a machinist. I have processed many orders for nuts like this to original equipment manufacturers. I don't know why they wanted them, as they were much more expensive than an off the shelf variety, but the engineers who designed them had a very specific purpose in mind. For whatever reason, they felt it was the best solution and must have had some sort of failure with a standard nut in the past and thus prescribed this one. I would not second guess the engineers on this one.

Perhaps an engineer or machine designer could jump in with an explanation.

Hmm... your post has got me thinking - never a good sign .

I had originally thought it might have been simply economics - back in the day (70s) making a nut out round stock being cheaper than using hex stock BUT...

Looking more closely, I note the "washer" bearing surface is part of the nut - normally not a big deal but I also note the number of threads engaging onto the shaft is not many, perhaps 4 or 5 only. Usually good engineering practice is to have at least 1.5 threads of the shaft protruding past the nut. For whatever reason, Yanmar has chosen not to do this so by using round stock and using the washer as part of the nut effectively increases the number of threads.

Even if this is just "once used horse oats", it prevents me from using a discrete washer and a standard hex nut - just won't be enough thread engagement to make me happy.

Additionally this lack of thread engagement might have been the reason to use a high strength thread sealant during initial assembly.

All of the above are just random thoughts from a "certifiable DIYer".

[Hillbilly]

Are you sure the so-called nut is really a separate part from the pulley. You could try turning the pulley. Even a large pipe wrench is a possibility but would have to be used with caution to avoid distorting the pulley. Even if the nut is separate, this might help loosen it.

[skipgundlach]

Originally Posted by Hillbilly

Are you sure the so-called nut is really a separate part from the pulley. You could try turning the pulley. Even a large pipe wrench is a possibility but would have to be used with caution to avoid distorting the pulley. Even if the nut is separate, this might help loosen it.

Reading the thread is awesome; you discover how it came off, and that the key prevents the pulley from turning!

[Hillbilly]

Are you sure the so-called nut is not really a part of the pulley itself? Have you tried to turn the pulley instead? Even if they are separate, that might give the nut some encouragement.