JD350 fuel injection issue

[AlexM]

Hi all,

I recently bought an old JD350 dozer. Not sure the year as it doesn’t seem to have a SN plate.
From what I’ve read in posts here it’s probably a 66-69 as it has the reverser lever on dash.

Ran fine and everything seemed to work as expected but when running last week motor quit and won’t start. I’ve read a lot of the posts here on fuel issues and think I’ve narrowed issue to the stanadyne injection pump. No fuel to injectors when I crack lines get nothing.

I’ve opened the inspection plate but see nothing moving in there when I crank it over. Just fuel drips out and does seem to flow to return line.

So my question is if shaft broke will low pressure still push fuel to return?
If I pull the pump does it come off shaft or do I need to remove from drive gear?
If I don’t see anything moving in timing window how would I set at TDC before removing and then set timing correctly when replacing pump?

I’ve never worked on one of these so any advice would be appreciated.

Thanks!
Alex

[Jim B]

If you don't have a technical/service manual get one before you go further, it will answer most of your questions and explain timing the engine, getting the pump off, and back on. Send Lavoy an email at postmaster@jdcrawlers.com, I believe he can help you with getting a manual.

If the shaft broke you will have to time it using different steps to confirm, than if it wasn't, since you can't line the marks up in the fuel pump window. If you are quite sure the shaft broke, get the engine set on compression TDC marks before pulling the pump. The rebuilt pump should come back to you with the marks lined up. I believe the shaft is supposed to come out with your pump after you remove three capscrews from the gear behind the small timing gear cover. Hopefully someone who has done one recently will post as well. Post the info from the tag on the pump.

[AlexM]

Thanks for the info Jim. I ordered a service manual so hopefully it shows up soon.

The tag on the pump had: Stanadyne DBGFC331-1AJ

[jsal]

had the shaft my 302 Jd industrial tractor break you need to pull cover on front and remove retainer nut then strike shaft to release shaft from gear as it is a tapered shaft

somehow my timing gears jumped and it was necessary to remove front engine cover and reset gear timing

JIM S

[gregjo1948]

Isn't there a check valve on the return line right where the line comes out of the pump? It's just a little ball in the fitting and if it' faulty, it may be your problem. Real easy to check. Right on top of the pump and easy to access. I'd check it before rebuilding the pump.

[AlexM]

Thanks for the info. I’ll check that return line fitting but it does seem to have fuel flowing in return line.
I got the manual so I’m going to check it out this morning.
Does anyone have part #s for the fuel filters in a Rosa Master housing? They have the holes on top but the ones on it have no #s... just Made In Mexico...lol

[Jim B]

They are both the same. John Deere # AT17387. Some options: Wix 33166, NAPA 3166, Baldwin BF259, CAV 296, and there are many other crosses as they are common filters. If you get Wix or NAPA (or other brands Wix may manufacture) they don't have a series of holes in the top of the element, they have a slot that looks like it would take a gasket around the inner top of the element. DO NOT put a gasket in the groove around the top in side those style elements, the slots in the groove is where the filtered fuel comes out of the element. The top gasket, with all the filters brands, goes up in the grooves of the housing head.

[AlexM]

Thanks Jim that makes sense about the WIX filters. I thought I’d gotten the wrong one.

Now my problem is the bottom nut on the IP mounting stud cannot be reached with any wrench I’ve got. There isn’t clearance to get anything on it due to location & pump housing being so close to nut

[AlexM]

Update:
Pump removed and Shaft was broken. Sending to shop for inspection & rebuild.
Had to tap that bottom nut off with a flathead screwdriver.
Thanks for all the info on this site. Hopefully I’m 1/2 way there:-)

[Jim B]

While your pump is at the shop, find an offset open end wrench the right size. Another option, if you have (or access to) a torch, you can pick up a couple "cost effective" wrenches the right size and custom bend them, stay close to the open end. You can do the box end, if it will fit in there on yours. You might want more bend on one than the other, to have more options to get another flat on the nut. I've got a set offset wrenches and a number of wrenches I modified to fit something at some point in time; often they come in handy for other things now.

Some guys complain about the Wix/NAPA fuel filters but I run mostly Wix filters and never had a problem with them.

[jsal]

most likely your pump is froze up may need to replace that is what i ended up doing the rotor assembly is like $800.00 with pump repair your at 1200 to 1500 so I purchased a new from JD. I made a wrench to access lower bolt. also on the filters i have found that the JD filters are cheaper than wix another brands and OEM quality!! I would also recommend that you clean your fuel tank !!

JIM S

[DrLoch]

If you got the part number off of it you may be able to find one on Ebay, a number of people offer them for less money than it takes to rebuild one in the condition of your's, broken shaft. That generally means the head unit seized.

[Stan Disbrow]

Hi,

The old style two-filter setup has a tendency to let crud thru when they load up. People tend to not change them often enough. Then, the crud causes the pump to turn hard. That leads to the safety neck-down on the pump drive shaft snapping.

Well, better that than ripping teeth off the timing gears.

Stan

[AlexM]

Hi Stan
You are right about those filters. In hindsight I wish I’d changed them 1st thing when I got the machine home.
The 1st was really plugged with lots of sluge in the bottom bowl. The 2nd bowl wasn’t as bad but they definitely should have been changed long ago.
The guy at the shop I’m working with told me i’ve got to determine what caused the seize or it will likely happen again. He’s going to inspect the pump I sent him to try to find out why it seized. I’ll post what I find so maybe others won’t have to go thru this.

Thanks
Alex

[jsal]

you need to clean your tank and blow all your lines out I took my pump apart my self and there was rust from water getting through filters and that is what seized the rotor shaft that broke the drive shaft this was on a 302 john deere industrial tractor

JIM S