Replacing a hydro pump in a d180

[tommyg 152]

I picked up a replacement low hours pump for may ailing d180 pump. I'm going to hope for the best and just do a direct swap out with the worn one. Is there anything I need to know regarding making sure the "new" pump is properly "primed" before I start everything up? I'm afraid of dry surfaces being damaged if they're not properly lubed before that first use.

[pfrederi 17,514]

There is no requirement to prime the pump but you want to make sure the pump has some oil in it to lube it during start up. You need to find out what fluid was used in your new pump. Some ran on ATF some use 10w-30 motor oil...they don't mix well. Also make sue you have the correct O rings and Backer rings. (A little grease will help hold them in place when you assemble it). This is not a 1 hour project, make sure you have an allen head socket to use on two of the manifold bolts. If your steering is loose it is a good time to adjust while the pump is out of teh way.

I have a poster

"Therapy helps...but screaming obscenities is faster and cheaper"

It is appropriate for this project.

Good Luck.

[Hodge71 664]

Tommy I hate to see you put all the effort into puttin the pump in and have it bad. You might want t open it up and make sure all is well internally. I also purchased what was supposed to be a low hour good pump and Paul and I opened it up only to find it full of rust and 3 out of the 9 cylinders shot from rust. Roll the dice if you feel lucky I guess. I just know from experience that its about a 3 hour process to get a pump extracted from the D. There will also be large amounts of cussing and a bit of bleeding. If you put a bad pump in multiply that by 2 so you can take it back out again after you run it. Also takin it apart will make sure you can lube it befroe reassembling and theres no chance of a dry start then...just my worth...Good luck to you either way. If you get nervous theres a post in the tranny section named rebuilding a hydro pump from a D. Its a collaboration between myself and Paul documenting my rebuild. It will help you in all areas

[Trouty56 565]

Most definitely read Jeff's rebuild post. Then read it again. Be sure to get a new set of orings and backers. Good time to change the filter. There is a line up tip in the manual that describes how to line up the pump with the manifold so the orings stay put using threaded rod as a guide. Lube the rings a little so they stick. I asked about priming when I had my pump off and a member suggested I raise the rear to take away as much pressure as possible from the pump letting the rear wheels free wheel. Run the motion from forward to reverse and use the lift. It will self prime. Have oil ready to fill the tranny after a short period of use and continue to check the fluid level. Good luck and remember to read Jeff's post.

[JamesBe1 82]

Been there done that (more than once). Don't forget to make the alignment studs to align the new pump when you put it in (I forget the size, but it's listed in the manual). You can take your chances with the old orings, but I would just replace them out of hand. If one gets misaligned during installation, it will get damaged when you tighten the pump to the manifold (and most likely leak). Even with the grease to hold them in place and the alignment studs, if one gets out of alignment, it's toast. It's good to have a backup set.

Like Paul said, don't worry too much about priming it, but make sure you have the correct fluid.

Oh yeah, when you break the seal to the manifold, it is going to leak all over the place. Best to put something down ahead of time.

All in all, it's not a job for the feint of heart.

[pfrederi 17,514]

Not to pile on but I replaced my pump shortly after I got my tractor. Messy not so fun project. However turned out the biggest problem was the hydro motor so then had to replace it,, but the replacement pump wasn't a big improvement. Bottom line I have to go back and replace it again. I strongly echo James Comments about opening your new pump and checking it out. I have purchased at least 4 motors and 2 pumps (most were from "working tractors") now that I know how to open them up it turns out all of them had issues!!!

Look at Jeff;s post. The pump is the easier of the two to open up. At least open it and check it out. Jeff made a gasket but they are still available from Toro for about $8

This is not something you want to do over again. Nor something you want to do in the driveway....

[JamesBe1 82]

Not to pile on but I replaced my pump shortly after I got my tractor. Messy not so fun project. However turned out the biggest problem was the hydro motor so then had to replace it,, but the replacement pump wasn't a big improvement. Bottom line I have to go back and replace it again. I strongly echo James Comments about opening your new pump and checking it out. I have purchased at least 4 motors and 2 pumps (most were from "working tractors") now that I know how to open them up it turns out all of them had issues!!!

Look at Jeff;s post. The pump is the easier of the two to open up. At least open it and check it out. Jeff made a gasket but they are still available from Toro for about $8

This is not something you want to do over again.Nor something you want to do in the driveway....

Actually, Jeff gets the credit for the suggestion of opening it up and checking it out.

I'm still a bit squeamish to open one up yet.

[tommyg 152]

Ugh! I know, Jeff, you're right. I never play the lottery but for some reason, I'm wanting to do that. Maybe because it's so unfamiliar. Maybe I will pull out that manual. I saw post about tearing one down and it looked really informative.

OK, so if I open her up, what exactly am I looking for?

[Hodge71 664]

Look at the condition of the slippers. They are the little brass "feet" located on the bottom of the pistons. They need to be free of scratches or marring of any sort and must have nice square shoulders with no rounding. Also look at the swash plate. This is what the slippers ride on. It is found on the bottom of the directional control plate. Its made out of steel and is polished. It should be free of scratches and marring also.If there is any scratches, have no fear, both slippers and swash plate can be poilshed with 1200 grit wet sndpaper and crocus cloth. The pistons will probably be fine as they are polished and then chrome plated and usually dont marr like the cylinder does which is raw metal. My cylinder was bad due to the water infiltration at some point causing rust. I probably could hone it but we had a spare that was perfect so it went in. There are specs for slipper thickness in the Sundstrand manual. Follow it and youll be fine. Dont hesitate to PM me if you have questions I will help anyway I can. Even if its talking you through it on the phone

[tommyg 152]

Jeff, that is an offer that I just might take you up on. I'll be in touch if (when) I get stuck!

[pfrederi 17,514]

To add to jeff's advice you also want to inspect the valve plate. It is steel on one side brass on the other. The brass side rides against the piston block and can be gouged by stray metal bits passing through the system. As with other parts use fine wet dry paper (wetted) on a piece of glass. The finish off dry (or with bit of light oil and crocous cloth.)

Here is the one I have been cleaning up.

[tommyg 152]

Thanks, Paul. I'll report back when I dig into it and let you guys know how I make out. Thanks for all the help!

[wheeledhorseman 574]

Good luck, you've had sound advice and can count on support but don't forget to post some photos to show us what you found.

The knowledge base on hydros in Ds is growing rapidly at the moment thanks to these guys.

Andy