perkins fuel pump leaking from unusual orifice

[brewdexta]

My mates JCB digger is dropping fuel and occasionally needs bleeding. After further investigation it appears to be coming from the flange shown, not the union, this is evident when you start it and it sprays out occasionally. And it is happening from two of them.

Given the nuts are not hex head, we didn't want to delve further without more info. Other than getting the right spanner, is this likely to be an easy fix, i.e. has anybody actually taken this apart before? If not we will take it down to a local garage if its beyond our expertise.

Red arrow indicates the flange where the diesel is leaking from.

Cheers
Andy

 

[mr migwire]

injector feeds from the pump by the looks of it, and good ole jcb with there special tools, fab up a tool and give them a nip up, but the "O" ring under the flange may need replaced....

 

[ben8vgte]

As that's an inline pump that will be the top of the pressure piston with the check valve in, never had one apart but it might have some little valve parts and a spring that could fall out if you took it off. Also you'd want that to be very clean round there before trying in case you get some dirt in, I'd suspect a new seal will be needed might be easy enough to do though.

 

[Badger1bear]

it may be a metal crush washer/ring if you take a look at this fleabay link

http://www.ebay.co.uk/itm/Jcb-801-4...arts_Vehicles_CarParts_SM&hash=item418bc37411

 

[wristpin]

May be worth posing the question on
http://www.ceforum.co.uk/

or here
http://www.classicmachinery.net/

Plenty of clued up plant people on both

 

[CRB]

May be worth posing the question on
http://www.ceforum.co.uk/

or here
http://www.classicmachinery.net/

Plenty of clued up plant people on both

Grief, I did not know what happened there, all of a sudden two quotes.

Thanks for the CEForum though. Some of our early LTs have Perkins four-cylinder diesels, gutless beyond belief, as far as I know.

 

[brewdexta]

Thanks guys.

injector feeds from the pump by the looks of it, and good ole jcb with there special tools, fab up a tool and give them a nip up, but the "O" ring under the flange may need replaced....

Fabbing the tool wouldn't take long, just need to know that its worth doing first. If it is an o-ring and easy to replace without a spring escape committee then we shall give it a go.

As that's an inline pump that will be the top of the pressure piston with the check valve in, never had one apart but it might have some little valve parts and a spring that could fall out if you took it off. Also you'd want that to be very clean round there before trying in case you get some dirt in, I'd suspect a new seal will be needed might be easy enough to do though.

It will be cleaner than an OCD nun after a long bath with a large piece of soap

May be worth posing the question on
http://www.ceforum.co.uk/

or here
http://www.classicmachinery.net/

Plenty of clued up plant people on both

That's an option , looks useful I shall have a chat with a mate of mine who refurbished the injectors for my dexta first before I join yet more forums!

Cheers
Andy

 

[MattF]

It will be cleaner than an OCD nun after a long bath with a large piece of soap

It's sounding like she could end up being quite a dirty little nun.

 

[mechman]

May be worth posing the question on
http://www.ceforum.co.uk/

or here
http://www.classicmachinery.net/

Plenty of clued up plant people on both

I agree with wristpin classic machinery net is the way to go
Norm.

 

[normspanners]

That is the japanese type perkins very similar to kubota this is for the 4 but same as 3

Here are the instructions to remove the injection pumps.

Remove bolts (4) and nuts (2) that fasten the fuel injection pump to the cylinder block.

Carefully raise fuel injection pump (1) from the cylinder block and remove clip (7) that connects link (6) to fuel rack control (5) .

Remove fuel injection pump (1) from the cylinder block.
Note: Record the thickness of each shim and the number of shims for reassembly. The fuel injection timing is determined by the shim pack thickness that is between the fuel injection pump and the mounting face on the cylinder block. For more information on the fuel injection pump, refer to Specifications, "Fuel Injection Pump".


Remove shims (3) from the mounting plate.




Specifications, "Fuel Injection Pump".



The shims adjust the timing of the fuel injection pump. A thicker shim retards the timing while a thinner shim advances the timing. The fuel injection pump timing changes one degree for each 0.10 mm (0.004 inch) difference in shim thickness. More than one shim can be used, if necessary.

Note: Do not use sealant on a shim. A thin layer of sealant is included with the final thickness of a new shim. Extra sealant will affect the timing of the fuel injection pump. If a shim is not required, a thin layer of 4C-9612 Silicone Sealant should be applied between the fuel injection pump and the cylinder block.

If a new fuel injection pump, or a new camshaft for the fuel injection pump, or a new cylinder block is installed, a new shim with a thickness of 0.5 mm (0.002 inch) must be used in order to correctly adjust the timing of fuel injection pump.

Refer to the Systems Operation, Testing and Adjusting Module, "Fuel Injection Timing - Check" topic for information on adjusting the fuel injection pump timing.

The following thicknesses of shims are available from your Caterpillar Dealer:


0.10 mm (0.004 inch)

0.20 mm (0.008 inch)

0.30 mm (0.012 inch)

0.40 mm (0.016 inch)

0.50 mm (0.020 inch)

 

[dannyp]

if it was me and my machene i would probaly just have taken it apart moreoften than not i find that non user servicable parts are easly serviced tho i know where you comeing from as have also had that OH F*** moment when realiseing that takeing it apart was not a good idea.

i recon mole grips for the silly nuts

 

[MattF]

tho i know where you comeing from as have also had that OH F*** moment when realiseing that takeing it apart was not a good idea.

Usually that moment when several bits go flying in different directions.

 

[500e]

Bits what bits Where

 

[normspanners]

Ha I stripped an old bale elevator pull cord down in a hay bay, and the whole unit had come apart inside there was a circlip unbeknown to me that had sprung, balls, springs, clips went everywhere, OH FLIP I said,
so i layed a grid out with baling twine and used a strong magnet along the grid lines, through, the hay and straw and every so often there would be a click and there would be a metal bit, unbelievably, to me as well, I found every part, and a few extra nails screws etc it took about 2hrs but quicker than running around for bits, new rope rebuilt it, perfect.
Ha thats brought back memories of balls in the spring in that haybay, the farmers daughter was gorgeous but that was another story-------

 

[brewdexta]

That is the japanese type perkins very similar to kubota

Thanks Norm, talking to my mate he believes it will only be a face joint between the flange and the pump on most, although a few have copper or ali washers as well. He concurred that first try and nip the strange bolts up but if that don't work then taking the flange bolts out for a peek shouldn't involve an explosion of bits. We are now in the barn, not the field so will be able to catch any shrapnel in a sheet depending on the exit velocity

He has a collection of spanners for these types of weird nuts so will drop by and see what he has before resorting to long nosed mole grips or fabbing up a spanner.

 

[normspanners]

The point was, if you take the whole pump unit off, you can strip and rebuild it easily on the bench. I have spoken with my mate the diesel pump specialist, and he said HE would not attempt it on the engine, BTW just nipping the nuts will not do it, also if just a flake of paint goes in it will seize the pumping elements and could screw the element or the thing will not start or if it does might not stop.
They have done loads of them and it is about a £180 job to reseal the Three, he said if one is leaking the others will not be far behind, because the special rubber seals go hard with the heat in the mini diggers.

 

[normspanners]

pentagon sockets etc http://www.lasertools.co.uk/item.aspx?cat=1067&item=10433

 

[brewdexta]

Thanks Norm, its unusual to use rubber at this pressure, must be special, my mate mentioned that the Japanese seemed to make the injector parts odd sizes on purpose so you couldn't use generic parts so using some weird rubber part to seal when a copper washer would do seems to be following their MO. I shall ask my neighbour how he wants to proceed as its his wallet

 

[normspanners]

The pressure is not that high where it will be leaking from, it will only be fuel chest pressure, that pressure forces the fuel into the pump elements to fill them when they are open, then, when that closes, the serious pressure begins, inside the pumping element/ injector pipes etc a little bit like the difference between low pressure veins and high pressure arteries in your body, they are seperate and diff pressures

 

[weldvandal]

I know i don't post here often but this youtube video might point you in the right direction

it's on a kubota engine but the pumps roughly the same.
just make sure that you align the flange with the two pentagonal bolts exactly as it was before removal as this adjusts the fuel delivery amount on that individual pump and nozzle.
is it a jcb 801 ?