Cat 311 Oil Level Up

thepumpguysc · Sep 14, 2020

There’s a seal under the roller in the spump.. they get hard n leak..
To confirm, remove spump.. block the outlet w your finger, apply air to inlet & spray w soapy water or dunk it in water n look for bubbles..
They r rebuildable..
Also check the banjo bolt on the bottom.. 10 bucks says it’s full of sticks

Mike007 · Sep 14, 2020

Thanks for that. I have the diagram of the pump and attached it below, which part is the roller?

I had the banjo bolt off but didn't see any sticks! How does that happen.

Nige · Sep 14, 2020

Mike007 said:
I had the banjo bolt off but didn't see any sticks! How does that happen.

Nobody bothers to drain the sediment & water from the fuel tank on a regular basis. The banjo bolt is the most restrictive part of the fuel lines therefore crap gets trapped there.

If you have an early 311 with no suffix letter then I show the transfer pump as a 5I- 7825. What is your machine S/No..?

Mike007 · Sep 14, 2020

5PK01111

6LK04180

Mike007 · Sep 14, 2020

Looks like I can replace the whole assembly $219.26 from Cat. But maybe I'll pull it off and see if there's a leak as thepumpguysc recommended before throwing parts at it...

Nige · Sep 14, 2020

Your machine is a grey market import 311A-model from the Japan-only market. The nearest equivalent outside Japan is a 9LJ-prefix machine of S/No 9LJ00262-Up.
Attached the appropraite spare parts diagram for that fuel transfer pump.

Mike007 · Sep 14, 2020

Thanks for that. The diagram you added looks to be the same pump diagram I attached. Except yours shows the roller thepumpguysc refers to but not the seal?

Nige · Sep 14, 2020

I think your best bet at this point is to remove the pump on your engine and take a look.
Using the equivalency chart I posted above is not guaranteed to be 100% acurate.

thepumpguysc · Sep 14, 2020

The supply pump is part of the injection pump parts group..
It’s a Diesel Kiki/Zexel pump..
If there’s a fuel inj. shop close by, they’ll rebuild it.. probably while u wait..
The seal is PRESSED into a hole & not easily extracted.. it takes years of practice to learn how to do it..(seriously)
The seal is more than likely NOT on any breakdown.. again, years of knowledge..

thepumpguysc · Sep 14, 2020

The supply pump can be gotten directly thru Zexel.. there’s a name tag on the supply pump..
But it can be rebuilt for around 100.00.. depending on if the piston is bad.. either way, your gonna be 100.00 ahead if u take it to the local inj pump shop..

Mike007 · Sep 14, 2020

thepumpguysc said:
The supply pump can be gotten directly thru Zexel.. there’s a name tag on the supply pump..
But it can be rebuilt for around 100.00.. depending on if the piston is bad.. either way, your gonna be 100.00 ahead if u take it to the local inj pump shop..

Thanks again! I'm in Vermont, there's not an injection pump shop within 100 miles. They quoted $150 plus I'd have to ship it there and back.

Do you have contact info for Zexel? Can't seem to find them on the net. Thanks

thepumpguysc · Sep 15, 2020

When I said u can order it direct, I meant the fuel shop can order it directly from Zexel..
Looking at your pics, the name plate is missing off the s pump..which doesn’t help..
You’ll have to get all the #’s off the main pump name plate, call a fuel shop & they can give u the s pump #..
When you call an AUTHORIZED Zexel dealer they’ll punch the # in & all the components pop up..
Pump, Gov & Supply pump.. for your specific pump #..

thepumpguysc · Sep 15, 2020

If u find it IS a bad seal leaking fuel into the engine & u wanna fix it yourself, your gonna need the parts..
Kit is a DGK 301H. Comes w hand primer.
1 oring that goes under the inlet fitting.
1 mounting oring.
1 piston.. If it’s scored..
And of course, 1rod seal..
Compare the prices of the parts to the cost of a new s pump..

Mike007 · Sep 15, 2020

I see your point, that kit is not expensive from what I can see on the net. But does it include the seal under the roller you mentioned earlier? Im definitely lacking the years of experience to replace that..

When I spoke with the repair shop he said I could remove the supply pump with the lines still on, actuate the hand pump and if fuel leaked out that would confirm it was bad.

thepumpguysc · Sep 15, 2020

No it does not include the seal..
THATS WHY I wrote: 1 rod seal..

u can check it that way if your lines were long enough..??
Most machines I’ve worked on have rigid steel lines..w no movement..

thepumpguysc · Sep 15, 2020

Why ask all these questions before pulling the spump.?? Pull the damn thing & get back to us..

Mike007 · Sep 17, 2020

Haha, yes I hear you.

Had time today so pulled it off. Left the hoses on and actuated the hand prime pump which resulted in fuel spraying out the top of the priming pump. I assume there’s seals in that that are bad? Not sure if that is the issue with fuel in the case.

I tried pressurizing as you described on the bench but no bubbles.

And yes, your $10 bet was a good one as there were sticks in the lower banjo bolt..

Cat 311 Oil Level Up

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