Crank Pulley Bolt - Trumpet Fitted...

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diffwhine
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Crank Pulley Bolt - Trumpet Fitted...

Post by diffwhine » Fri Aug 07, 2020 6:32 pm

Having rebuilt my 2.25 engine (236 and original to the vehicle), I'm now at the point of sorting out crank pulley bolts. When I got the vehicle, it had no crank bolt on at all. Clearly somebody had robbed it which makes me think that it probably had one of those trumpet guides for the crank handle.
I have both versions - with and without the trumpet, but assuming that originally it would have had a trumpet dog fitted (I stand to be corrected...), how on earth are you supposed to torque up the crank pulley bolt if a trumpet is fitted? I think the nut size is 1 5/8", but clearly a ring spanner or deep socket won't fit over the trumpet. Putting my truck engineer hat on, I assume the answer is an open slogging spanner, but without going back to my O level physics and working out how to measure the torque, is there a simple method of doing this. How did the Army do it?
Clearly a slogging spanner being given a good thump and then bending over the lock washer and all should be fine. I just want to understand what tools Her Majesty's Finest would have used if doing it by the book...
Have I just answered my own question?

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AR4412
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Re: Crank Pulley Bolt - Trumpet Fitted...

Post by AR4412 » Fri Aug 07, 2020 7:33 pm

diffwhine wrote:
Fri Aug 07, 2020 6:32 pm
how on earth are you supposed to torque up the crank pulley bolt if a trumpet is fitted? I think the nut size is 1 5/8", but clearly a ring spanner or deep socket won't fit over the trumpet. Putting my truck engineer hat on, I assume the answer is an open slogging spanner, but without going back to my O level physics and working out how to measure the torque, is there a simple method of doing this.
Ah. You must be thinking of the 'Torque wrench extension calculation formula', T x L over L + E = Y.

T - Desired torque at the end of the extension.
L - Length of the torque wrench.
E - Length of the adaptor.
Y - Final torque value applied to the wrench. (Torque wrench setting.)

An open ended spanner can be adapted, bent to fit around the pulley, and a socket welded to it to allow the torque wrench to be attached to it.
diffwhine wrote:
Fri Aug 07, 2020 6:32 pm
How did the Army do it?
Clearly a slogging spanner being given a good thump and then bending over the lock washer and all should be fine. I just want to understand what tools Her Majesty's Finest would have used if doing it by the book...
Have I just answered my own question?
Yep. Give the slogging spanner a damn good welly or two then bend over the locking tab. Job done.

PS. I'm not smart enough to work out that formula myself. I have it from when I did my Vehicle Mechanics course, and kept a copy of it.

Regards,
For Those That Have Had To Fight for It, Life Has Truly A Flavour The Protected Will Never Know.

'First my weapon. Then my equipment. Then myself.'

Neil.

09FM98. 1973 Ex SIII FFR Now 3.5 V8 LWT Coiler.
55HG98. 1980 SIII FFR PARA RECCE. Ex 1, 2 and 3 PARA.
Td5 90 XS.

diffwhine
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Re: Crank Pulley Bolt - Trumpet Fitted...

Post by diffwhine » Fri Aug 07, 2020 11:47 pm

Thanks!
Slogging spanner and a bit of welly it is then!
I've just seen that the torque extension calculator is available as an iPhone app now!
Is there anything that doesn't have an app?

The more useful calculation is the one which factors in the use of extension bars on torque wrenches

I think I've found an 1 5/8" open slogging spanner which is good news because new ones are not cheap!

Pilgrimmick
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Re: Crank Pulley Bolt - Trumpet Fitted...

Post by Pilgrimmick » Sat Aug 08, 2020 8:07 am

We used to have a full (?) set of slogging spanner’s at work from about half inch up to about six inches (yes six inches, it was a ship’s set) I returned one day to find they had been thrown away and replaced with a set of Britool combination spanners.
The new engineer thought they were just a set of very old spanners and that replacing them with new and more compact spanners was a good thing. I nearly cried.
Probably several thousand pounds worth. :?

Johnsboy
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Re: Crank Pulley Bolt - Trumpet Fitted...

Post by Johnsboy » Sat Aug 08, 2020 8:34 am

Torqued mine up with a bolt shank that just fit in the starter dog hole. The bolt was drilled to take a pin mimicking the starter handle. Torque wrench clicked at the right value but don’t think the bolt was up to it as it had started to twist where it was drilled but job done.

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ianmaiden
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Re: Crank Pulley Bolt - Trumpet Fitted...

Post by ianmaiden » Fri Aug 14, 2020 5:23 pm

I had the problem trying to remove nut with trumpet, I caused more trouble bashing the spanner as it didn't fit nut tightly as it has to be at an angle to fit inside pully wheel,it just rounded nut making more trouble. Ended cutting off trumpet and buying new nut. There must be a specialized tool in a army REME parts catalogue. I hope someone can help??

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AR4412
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Re: Crank Pulley Bolt - Trumpet Fitted...

Post by AR4412 » Sat Aug 15, 2020 10:11 am

ianmaiden wrote:
Fri Aug 14, 2020 5:23 pm
There must be a specialized tool in a army REME parts catalogue.
Not that I was aware of at unit level. There is a Land Rover Special Tools spanner for the standard starter dog shown in the back of the workshop manual, but I'm not aware of there being an 'open jaw' version to fit the starter dog with a guide on it. In true REME fashion the special tools were a large hammer, a punch and some brute force, or if you were really posh, a spanner was taken to the metalsmiths bay, heated up with the gas kit, and bent in the vice to suit the job in hand. Removing the bottom pulley wasn't a common job to do, so if it had to be done, you tackled the job as best as you could with the tools you had at hand. It might have been a different story if you were at a District/Base Workshop/ABRO and your day job was stripping and rebuilding 2 1/4 engines.

Regards,
For Those That Have Had To Fight for It, Life Has Truly A Flavour The Protected Will Never Know.

'First my weapon. Then my equipment. Then myself.'

Neil.

09FM98. 1973 Ex SIII FFR Now 3.5 V8 LWT Coiler.
55HG98. 1980 SIII FFR PARA RECCE. Ex 1, 2 and 3 PARA.
Td5 90 XS.

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Loulou
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Re: Crank Pulley Bolt - Trumpet Fitted...

Post by Loulou » Mon Aug 17, 2020 4:06 pm

Hi,
Specific process implemented for my engine.

Disassembly:
15 days drowned in penetrating oil
Destruction of the "trumpet" shape with the grinder
Manufacture of an elbow wrench to properly hang the nut
Jack up under that key and… yyarrgggh!

Reassembly:
Purchase of the civilian spare part without the trumpet
Reassembly (with copper grease) using the eye wrench suitable for the torque wrench

Servant :mrgreen:

Regards.
Looloo
27GJ77 - 1977 LWT SIII FFR - 1st. Royal Horse Artillery - B Battery (BAOR)

diffwhine
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Re: Crank Pulley Bolt - Trumpet Fitted...

Post by diffwhine » Fri Aug 21, 2020 11:36 am

I did finally mange to do it up!
No idea how I'll undo it again if I have to, but I made this from a hardened steel pin and an anti roll bar bolt / pin from a Defender. Worked a treat!
Not sure how many times it would work without sheering, but once was enough! I made it a sleeve fit into the crank dog and the hardened pin is an exact fit to the profile of the dog at 9mm.
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Loulou
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Re: Crank Pulley Bolt - Trumpet Fitted...

Post by Loulou » Fri Aug 21, 2020 3:00 pm

Well done !
Nice idea, the triumph of thought over muscle.

Regards.
Looloo
27GJ77 - 1977 LWT SIII FFR - 1st. Royal Horse Artillery - B Battery (BAOR)

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