My poorly 3c Mk2

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Danngerous
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My poorly 3c Mk2

Post #1 by Danngerous » Wed Oct 12, 2016 7:56 pm

I've just bought an old 3C. The previous owner had gone some of the way to re-furbishing the machine but seems to have given up and left some jobs unattended.

Great example. I bought the machine at a greatly discounted price after discovering a coolant rad half full of engine oil. When I got the machine home I was fully expecting to have to replace head gasket/head or have to carry out some other time consuming job. Before I started stripping it I thought I'd just check the head has been tightened down correctly. To my surprise I found all the bolts little more than finger tight. I've tightened them back down and have removed the rad to flush it then hopefully it will stay clean.

Here is my 1st question: Does anyone know if there is a solvent I can use to clean all the oil out of the engine and rad?

Whilst I was doing a bit of a once over I decided to whip the sump off and check the condition of the shells as when warm the oil pressure isn't great. There was some bearing material on the sump plug and in the bottom of the sump, not loads but any is too much. I removed No4 cap, the bearing's not gone but it's not in great condition so I'm going to replace the lot. Just to clarify, the engine sounds really nice but being a mechanic I'd rather perform preventative maintenance now than fir a new crank later.

Question 2: Is there anywhere people use for shells and are they all the same for all the 3.8TD engines? Also, are there any downloadable manuals?


Some of the other bits they have neglected are the track rod ends have an amazing amount of play in them and are not tightened into the hub properly so the steering is a little vague. The back hoe has a serious amount of play in the slew gear (I think) and the king post seems to be a bit all over the place.

Any way, any advice or help would be fantastic, this is my 1st foray into the world of classic machinery and so far, I'm loving it. Here is a photo of my 3C and old Bentford dumper.


Image
Last edited by Danngerous on Wed Oct 12, 2016 10:14 pm, edited 1 time in total.


Jeremy Rowland
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Re: My poorly 3c Mk2

Post #2 by Jeremy Rowland » Wed Oct 12, 2016 9:41 pm

Ian as regarding question 2; you firstly need to ascertain if the old shells fitted are standard? I know that on some engines you will find STD stamped on the outside of the shell for standard shells and 010, 020, or 030 for ten thou, twenty thou etc. shells for a crank that's been reground. I would get the shells changed if I were you but you must also check that the crank does not require a grind or a polish, check for ovality using a micrometer and also check that there are no 'tram lines' scored on any of the journals. Personally I would want to strip the whole lump down and clean it out thoroughly if going to such a lot of trouble but that depends on what you want to use the machine for and how long you would want it to last?
There are other JCB fans on here who will offer you some good advice. :thumbup:

Jeremy


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Re: My poorly 3c Mk2

Post #3 by Danngerous » Wed Oct 12, 2016 10:14 pm

Hi Jeremy.

I've removed a bearing and have the number off the back, there doesn't seem to be a STD or +xx though on them. They have a symbol on followed by A5689. the journal I've exposed isn't in bad condition but obviously with the age of the engine, it's not like new. Getting a regrind here would probably work out more expensive than a new crank off somewhere like Agriline where if they are the right part, cranks are £260. It's not so much the money, it's the amount of work involved.


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Re: My poorly 3c Mk2

Post #4 by Jeremy Rowland » Thu Oct 13, 2016 7:40 am

Danngerous wrote:Hi Jeremy.

I've removed a bearing and have the number off the back, there doesn't seem to be a STD or +xx though on them. They have a symbol on followed by A5689. the journal I've exposed isn't in bad condition but obviously with the age of the engine, it's not like new. Getting a regrind here would probably work out more expensive than a new crank off somewhere like Agriline where if they are the right part, cranks are £260. It's not so much the money, it's the amount of work involved.



Ian I cannot identify your shells any further than what you have described; perhaps somebody can give you advice or a bearing supplier, if you have a manual you can measure the crank journal with a micrometer and it will tell you immediately if the crank has been previously reground, personally I suspect that you will find it is standard but that has yet to be ascertained.

Jeremy


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Re: My poorly 3c Mk2

Post #5 by Danngerous » Thu Oct 13, 2016 9:00 am

I just need some time to strip the rest of the shells and I'll measure them. I know a really good engine builder I used to use in the UK who will post them to me if needed.

Thanks for your help.


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Re: My poorly 3c Mk2

Post #6 by Danngerous » Thu Oct 13, 2016 10:17 pm

One last question. I've bought a manual but will have to wait for it to be delivered. In the mean time, could anyone tell me the torque settings for the mains and big end caps please.

The crank has some significant ware on no 2 &3 big end journals but I'm going to put it back together and run it as is until I either go back to the UK and can take it with me or until it dies. I've been in touch with my old engine builder in the UK how says he has 3 or 4 old serviceable cranks knocking round his workshop.

TIA

ian

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Re: My poorly 3c Mk2

Post #7 by FOWLER MAN » Mon Oct 17, 2016 1:48 am

Hi Ian.
Big ends 60 Lbs. Ft.
Mains to engine No,56130 100 Lbs. Ft.
From No. 56131 or "any" engine fitted with washers 120 Lbs Ft.

I don't know how bad your shells are :?: :?:
When shells aren't too badly worn I have sometimes found it better to put back the old shells which will be work hardened than to put new softer shells with a worn crank as they could possibly wear very quickly. :think:

Fred


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Re: My poorly 3c Mk2

Post #8 by Danngerous » Mon Oct 17, 2016 8:34 am

Hi Fred.

Thanks for the info, I found it the other day on the net so put it back together yesterday with the old shells and some thicker oil. The oil pressure is a bit better but still not what I'd want but it has work to do. I called a friend in the UK who has an engine refurb shop, he said he's got 3 or 4 cranks lying round sp I can run it and if the worst happens I know I'm sorted. The shells weren't that bed, it's more the journals of the crank are really bas;y worn on the thrust face so will almost definitely be oval. I'm going to get the clutch done in the Manitou so I can use that to lift the engine either when the time comes or before I return to the UK.

Next thing to do is to find a manual and try to figure out how to adjust the King post. The slew gear is looking to be very worn, the boom has about 30 degrees of play in it!

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Re: My poorly 3c Mk2

Post #9 by Mark.Rive » Fri Dec 09, 2016 9:09 pm

The proper workshop manual for your machine is available in the downloads section at the top of the page :) Mark


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Re: My poorly 3c Mk2

Post #10 by Danngerous » Tue Dec 13, 2016 7:10 am

Thanks a lot for that mark. That will come in most handy.


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