450G fuel in oil

[allen_shelton]

I've got a 450G...late 80's...maybe even very early 90's that's been sitting for a few years and I'm trying to put it back to work. We parked it when it basically quit running. We got the injection pump rebuilt and put it back together but never got farther than that. Now that I'm trying to get some use out of it I've found it's getting fuel in the oil. I did replace the lift pump hoping that was it but I've changed the oil three times and still apparently no better. It's blowing out the crankcase breather tube at around 1/2 throttle. As far as I know the only way fuel can get in the oil is either the lift pump or the injection pump, right? I've seen umbrella seals mentioned in other posts. Are we talking about something that would require disassembling the pump or seals that can be accessed by just getting the pump off the tractor? I'm fine with getting the pump off the engine...not that confident about taking one apart completely. FWIW, it runs perfectly...idle to wide open...makes good power, etc.

[Jim B]

Welcome to the Board.

Yes, the umbrella seals will let fuel into to engine. The seals are on the shaft so the pump doesn't need to be torn down; as long as the bushing in the pump where the seals run is in good condition. The technical manual should have a good description of doing the pump removal and installation. You need to properly position the engine and pump by the manual, as far as timing marks. Pull the injection pump off. The pump should slide off the shaft and the shaft will stay in the engine. The seals will be on the shaft. If they are the common cup type seals, the open end of one cup should face forward and the other cup open end faces rear. Use care installing the pump over the seals, the rear facing one in particular as it is easy to tear the lips which will lead to a leak. They do make/sell a tool to aid in the installation of the umbrella seals but they can be installed without it, if care is used.

To get the right seals you will need your crawler, engine, and injection pump model/serial numbers as the parts catalog shows a couple different pumps using different shaft seals. If you don't have them I recommend you get the Technical Manuals for your machine. They are TM1403 for testing and TM1404 for repair. Check with Lavoy (email postmaster@jdcrawlers.com), he may have equivalent manuals in the line he carries in his store.

[77 Ford]

If you've had the pump rebuilt recently more than likely the bushings are good. I think it's fairly common to tear the seals while installing the pump. I used a big zip tie to compress it till it started in the hole.

Good luck.

[DrLoch]

If you've had the pump rebuilt recently more than likely the bushings are good. I think it's fairly common to tear the seals while installing the pump. I used a big zip tie to compress it till it started in the hole.

Good luck.

I used the tool (Stanadyne #13371) and the zip ties in the past. I believe the seal is a 10453, I generally get extras.

[DrLoch]

BTW the seal number is a Stanadyne number not a Deere number

[allen_shelton]

Thanks to all of you for the info. It'll be a few days before I get the chance to fiddle with it again. I'll post what I find. Thanks again.

[allen_shelton]

Well, I finally got a chance to mess with the dozer. As mentioned in the posts above it was the rear seal that was shredded. I don't know how to post a picture but if you can imagine the seal with about 1/3 of it cut off then that's what I found. I changed the oil and ran it for about a half hour. The next time I can get home before dark I'll hopefully find that it's no longer making oil. It certainly can't be much worse than it was. Thanks again for the info.