Resealing a CAV pump

[Ultradog MN]

The pump on my 3000 is leaking badly.
The tractor runs good, just the pump leaks.
I'm thinking about trying to save the $850
the pros always want to charge to even
touch a pump, buying a seal kit for ~$50
and doing it myself.
Have had the top cover raised on a few of
them to free up a stuck metering valve but
never went farther.
I don't usually like youtube videos as they
are always too darned talkative.
But I watched the video below and thought
it was pretty good.
He's a little crude but...
Helped me to get past the scared a little..
It doesn't look too hard.
Any thoughts?
Click here

 

[warbaby]

Admittedly, I didnt watch the whole thing yet, but the first thing that caught my eye was how dirty that pump still was as he began to take it apart. Grease and dirt in every nook and cranny.

If theres one rule you have to follow when dealing with the fuel system it is to KEEP IT CLEAN! That goes for gasoline or diesel, but those diesel pumps and injectors with their tiny precision bits & pieces and tight clearances are especially unforgiving.

I wouldnt be afraid of a resealing job though, as long as it worked fine beforehand (I'd still keep a look-out for worn parts and possible future trouble) and you maybe take a few reference pictures for reassembly and retiming of the pump, KEEP IT CLEAN, and dont have any spare parts left over that you didnt have when you began, you should be good.

If not, theres always Dieseltech...

Now I gotta watch the whole video just to see if it works when hes done with it.

 

[JWA]

I'm in the same situation, runs great, pump leaks badly, I have the kit sitting on the workbench staring at me just a little intimidated. Reminds me of my first automatic transmission rebuild and it and several more have been successful. I will probably tackle it soon. Wish me luck and the same for you.

 

[Bern]

I agree with warbaby, that video was cringeworthy. I will never take advice from someone who is that careless with regards to dirt and fuel systems. My pumps are spotless before I take them apart.

That said UD, I think highly enough of your mechanical talents that I do believe you could do it yourself. Just don't undo or mess with any adjustments and you should be fine.

 

[warbaby]

I swear that pump was cleaner BEFORE he removed it!

 

[Ultradog MN]

What?
You mean you gotta clean them?
Lol.
I liked him tho.
No BS.
I will get a seal kit ordered.
New oring for the shut off valve too.
Am embarassed how filthy my tractor is.
Thanks

 

[sotxbill]

I reseal mine while still on the tractor.. and its a challenge, but it works in the 4 or 5 times I have done it. Some of these pumps have a two piece fuel rod while others have the single piece rod that goes through the top cover. Its very very very easy to not get the two piece rod pushed back together and thus have no throttle control... so that is just one more gotcha to look out for. Also someone was.... selling just the reseal kit only on ebay... for around 15 bucks so you did not have to buy the full kit.. I should have bought more of them.

the last one I did on a 3600...kept blowing the cover gasket.. even after doing it several times. Found the return line was plugged with some snot and once I clear it, it worked fine... So even one more gotcha.

hope this helps.

 

[Bern]

To be fair, the visible side of the pump was clean before he removed it. Once he put it in the vice, we were looking at the backside of it. Still no excuse though for him not to clean that crap off before he took it apart.

 

[Check Break]

(quoted from post at 06:19:19 02/12/23) The pump on my 3000 is leaking badly. The tractor runs good, just the pump leaks. I'm thinking about trying to save the $850 the pros always want to charge to even touch a pump, uying a seal kit for ~$50 and doing it myself.

Something I wanted to do for a long time also, so when I bought a 445A with a stuck pump, I figured I'd give it a try, and if I failed, it was going out for repair anyway. That turned out to be a success without having to disassemble the main pump (didn't have the tools), so when biology overwhelmed my 4000, I tried my luck again, this time with some tools I bought out of Italy. The socket I bought to remove the advance pin failed, so it, the cam and snap ring stayed in the case, but everything else got disassembled and cleaned. Three or four cans of break clean are all you need. Took careful measurements of the pump settings before taking the main pump apart and had no trouble putting it back together. The DPA is pretty uncomplicated after you play with it for a few hours.

There's more videos if you look around. This guy has three on his DPA rebuild. https://www.youtube.com/watch?v=PVYHV5O9_CQ If you poke around, you'll find more from a couple of different perspectives.

My biggest problem with the 4000 was the lift pump. The gasket sold these days doesn't fit the old plunger causing lift pump failure. I knew I had a problem before reinstall, but there was fuel at the pump bleed screw, so I was extremely disappointed when I didn't have enough fuel at the injectors. Figured I'd screwed up the main pump. After pondering it a few days, and trying to make my own lift pump plunger gasket, I swapped the 4000's lift pump with the newer style on the 445A. Instant success, so live and learn. That DPA lift pump is critical to the function of the main pump. It's not like an old Caterpillar that will run with a little more head pressure or line pressure.

If all you're going to do (or do now) is reseal the top cover, just take lots of pictures and you'll be fine. If you want to replace the input shaft seal and the oring between the main pump and case, they it would be best to remove the DPA and work on it on the bench. From my experience, an OEM gasket works best when resealing the timing cover.

I want to say there's two orings on your fuel shut off valve. I found a package of five in my Ford drawer the last time I worked on one, but am armed with Viton now. Want to say they're a -010. You only need them on Sundays and holidays.

 

[Check Break]

(quoted from post at 06:19:19 02/12/23) The pump on my 3000 is leaking badly. The tractor runs good, just the pump leaks. I'm thinking about trying to save the $850 the pros always want to charge to even touch a pump, buying a seal kit for ~$50 and doing it myself.

Something I wanted to do for a long time also, so when I bought a 445A with a stuck pump, I figured I'd give it a try, and if I failed, it was going out for repair anyway. That turned out to be a success without having to disassemble the main pump (didn't have the tools), so when biology overwhelmed my 4000, I tried my luck again, this time with some tools I bought out of Italy. The socket I bought to remove the advance pin failed, so it, the cam and snap ring stayed in the case, but everything else got disassembled and cleaned. Three or four cans of break clean are all you need. Took careful measurements of the pump settings before taking the main pump apart and had no trouble putting it back together. The DPA is pretty uncomplicated after you play with it for a few hours.

There's more videos if you look around. This guy has three on his DPA rebuild.
https://www.youtube.com/watch?v=PVYHV5O9_CQ
If you poke around, you'll find more from a couple of different perspectives.

My biggest problem with the 4000 was the lift pump. The gasket sold these days doesn't fit the old plunger causing lift pump failure. I knew I had a problem before reinstall, but there was fuel at the pump bleed screw, so I was extremely disappointed when I didn't have enough fuel at the injectors. Figured I'd screwed up the main pump. After pondering it a few days, and trying to make my own lift pump plunger gasket, I swapped the 4000's lift pump with the newer style on the 445A. Instant success, so live and learn. That DPA lift pump is critical to the function of the main pump. It's not like an old Caterpillar that will run with a little more head pressure or line pressure.

If all you're going to do (or do now) is reseal the top cover, just take lots of pictures and you'll be fine. If you want to replace the input shaft seal and the oring between the main pump and case, they it would be best to remove the DPA and work on it on the bench. From my experience, an OEM gasket works best when resealing the timing cover.

I want to say there's two orings on your fuel shut off valve. I found a package of five in my Ford drawer the last time I worked on one, but am armed with Viton now. Want to say they're a -010. You only need them on Sundays and holidays.

 

[Dieseltech]

I watch those videos for my entertainment, a lot of what is done is not how the CAV DPA service training taught us years ago at the Highland Park Michigan school location...

 

[Eman85]

I watched that video and a couple of others before I tore mine down. I hadn't resealed an injection pump since the 80's when I worked at an Oldsmobile dealer doing Roosa-Master pumps. I do have a shop, a safety clean, plenty of brakekleen and some grasp on what I don't know. Kept everything clean and resealed my leaking CAV pump on my 2600. Been a while now, no leaks and tractor has been doing fine. I took it down all of the way and replaced all of the seals.

 

[used red MN]

UD, main thing is ultra-sterile. Clean pan of solvent and anything you have staged to install as final assembly is dipped..cleaned in the solvent and either set on a lint free surface like old brown folding paper towels, those you used to see in filling station bathrooms or dried with compressed air. NO LINTY RAGS TOUCH ANYTHING!! In my opinion most paper towels for household use have to much free or loose surface crud for this purpose. I have done some Roosamasters but have not been in a CAV. If you run into trouble give me a call I have some contacts that may be able to give some help.

 

[Ultradog MN]

I wouldn't have watched 53 minutes of that video either. But it is that or spend the $850.
He does clean it.
Eventually.
I kike lacquer thinner for that kind of stuff.
A quart of it in a clean pan.
I ordered the kit from here this afternoon.
Won't do it right now. Have 2 months of possible snow yet and need the tractor.
Unwinterize the pressure washer first when it can no longer freeze.
There's other videos too.
I guess it's my turn...
Thanks to all.

 

[Hobo,NC]

In the last year I have put new o-rings in two shut offs. I dunno if I wrote down the #. I had the o-rings in stock noting special about them.

With the money you save sealing the pump buy a O-ring cone, life will be good. Before I brought a cone a retired machinist schooled me on sizing o-rings. I cheated sometimes, The local Mill supply has a cone with a good assortment of O-rings.

Cone

 

[Eman85]

(quoted from post at 05:39:40 02/13/23)
In the last year I have put new o-rings in two shut offs. I dunno if I wrote down the #. I had the o-rings in stock noting special about them.

With the money you save sealing the pump buy a O-ring cone, life will be good. Before I brought a cone a retired machinist schooled me on sizing o-rings. I cheated sometimes, The local Mill supply has a cone with a good assortment of O-rings.

Cone

I can take the rest of today off, I learned something. Never saw an O-ring cone before. I've got the o-ring charts in US and Metric and thought I was doing good.

 

[Hobo,NC]

I have -009 highlighted in an o-ring box as Ford Tractor shut off. I can not guarantee its for a thousand series but would be a good place to start.

 

[Eman85]

When I figure out an application I make notes in my O-ring box for this as the old memory ain't what it used to be.