JCB 3C MKIII /5 picts and questions

[Unknown1875]

Today I had the chance to remove the radiator and the water pump, the water wasn't as dirty as I thought. I cleaned the radiator. The good news is that none of the bolts were seized I tried those from the exhaust manifold too. Water pump seems ok i wasn't expecting something that well built !
I think i'll pop the head off anyway, I'll have the chance to check the valves seat that way. I have time and parts will soon be there so why not.
Here are some picts after some pressure wash:

[Unknown1875]

update :
I've been waiting for parts and tools so I decided to change the seat, the new one comes from a Peugeot Expert
Before :

During :




After :

[Unknown1875]

More update :
Parts and imperial tools have arrived !


Time to pop the head off



So far so good, access is luxurary and every bolt is well lubricated, i 've found out that all the screws from the head cover weren't tight. That might explains a few leaks !
Ok here comes the hard part (you know there is always one). The head is well stucked, I've come up with this technic but the only thing I managed to get is a crack in the wood.
I'v tried to hit the head with a mallet too but nothing.
I let things cool down since I don't want to do any stupid thing.
Any advices on how to gently unstuck a head would be greatly appreciated.
I've already double check any remaining bolt, I will read the manual to see if I'm missing something.
So far my only thought is bigger piece of wood and stronger strap ^^

[agrimax]

Put the battery in and try a few turns of the key.Just might get it unstuck.

[Jeremy Rowland]

Louis your first port of call with the head is to double check that you have all the bolts/nuts which secure it removed; although I am not familiar with this engine by experience of working on other engines, the cylinder head can sometimes be stuck, I generally used the handle part of my 1/2" drive breaker bar in one of the ports and give it a good jerk, that normally does the trick, or you can try what Agrimax has suggested, although I have never done that or seen it done, I have heard of other people releasing stuck cylinder heads that way before.
Let us know how you get on.

Jeremy

[Unknown1875]

Thank you both for your advices, I will try these tomorow. It should pop one way or the other ^^
I will post the inside for sure, I can't wait to see if that's a keeper or not.

Btw I did some research in order to adapt a grass cutter/bush hog on it. Apparently many americans (propably other too) convert 3 points PTO bush hog to hydraulic and mount them on their bobcat. From what I understand It appears doable, the hydraulic output should be around 32 gl/min or 110L/min (high flow).
But where to plug it? I have the double hydraulic pump, one extra for the extend hoe. Therefore auxilary pump should be too weak (~40 L/min ).
Is this knob a free output hydraulic port ? If free that would mean putting a relief valve + solenoid distributor + by pass valve right ?
Thank you

[Unknown1875]

Yes ! Head is out.
Finally I 've found a spot designed to put a lever. I tried plastic first but steel was the way to go.
I did tried gummy fiber handles in ports but they were too short to apply enough force. I was too shy to crank it. I thougt it might have disturbed the sleeves but maybe I'm wrong.
I wasn't prepared for the weight of that thing !
I'm quite happy with the look of the inside tell me what you think, cylinders are markless and really clean, a bit of calamine but no sign of bad compression IMO. The gasket appears to be well soaked in oil not sure if it was like that before disassembly.

Now a lot of cleaning awaits me and I 'll try to check valves seats.

[Jeremy Rowland]

Louis glad you finally got the head off it's hard to see from the photos but apart from being a bit coked up it doesn't look so bad, so long as there are no score marks on the cylinder bores indicating a seizure, carefully turn the engine over by hand to see each bore. Can you see any area where oil has passed through the head gasket to the cooling system?

Jeremy

[essexpete]

I think hydraulic male quick release is a pressure test port. I wonder if the size fitting would allow sufficient flow and/or cause over heating. Need a hydraulic gurus! You would need a control valve block with in easy operation reach complete with a suitable relief valve. The return, I guess, would need plumbing into the tank and preferably below oil level to stop foaming. I am a complete amateur so you would need to check properly.

[FOWLER MAN]

Hi,
The arrowed knob as you call it on the hydraulic pumps connection is a self sealing coupler for connecting a test gauge. Wherever you connect your attachment it is important to connect the return to an existing return, (exhaust), line so that it is returned through a return line filter to the tank.

I worked on these engines years back and I'm afraid that not only were they prone to seals leaking at the base of the cylinder liners but in long service engines the liners sometimes crept down into the block.

When fitted the standing height of the liner must be between .003 and .006 inch above the face of the block. shims are available 3, 4, and 5 thou. thick to sit in the block under the top flange of the liner to achieve the required height. Most importantly the standing heights of all liners should be not less than .003 and as near as possible the same on all cylinders.

When you get it all cleaned up get some feeler gauges and an engineers rule, ( I have used the back of a hacksaw blade ), and check them carefully.
This is definitely worth checking as the brown sludge in your radiator is a fair sign that combustion gases have been blowing into the water jacket.
Let us know what you find.
Fred