350B Water Pump

[Kaiverol]

My 350B started leaking coolant in the summer and based on best observation I suspected the water pump. Sure enough after removing it the shaft has significant play where you can move the impeller sideways at least an eight of an inch. I read that rebuilding is the way to go so I want to try do it myself. Unfortunately I do not have a press and don’t think I can hammer the shaft out etc. The most I was able to do myself so far was the remove the pulley hub with a puller.

If I go down the path of purchasing a press are there any tonnage suggestions or other tips? Or should I bring it to a shop?

As far as parts, I need a seal kit and a new bearing and of course gaskets. I saw a video where they were installing a new impeller as well, but I’m not sure why? Also, where is the best place to get these parts? Thanks for any help and advice.

[Jim B]

You are in Canada and I don't know what shipping costs and such amount to but checking with Lavoy is one good possibility. If he can't help you, I would go right to John Deere. It looks like your 350B water pump takes the same rotating parts as my wheel tractors use (the rotating wear parts are common in many JD water pumps, the housings change). I have been getting the full kit JD offers (includes multiple gaskets for the different applications it covers) for them which has the seal, tool to press the seal in, bearing/shaft, and impeller. The local dealer stocks the kits, not all the individual parts. JD had some impeller issues in the past with plastic impellers some pumps came with as original equipment, so the kit has a new metal impeller. I install the new impeller anyway, even with the old one being metal, my thought is there less chance of the new one slipping on the shaft. Yes, you need a press, or you need to take it to a shop with a press. You need the tool to install the seal. Did you measure and write down the shaft protrusion (if any) before you pulled the hub off? Matching dimensions is critical for reassembly.

You can check a water pump while on the engine by taking hold of a fan blade at the top and try moving it front to rear. If it rocks at the pump (no the blade flexing) the bearing is going, and the pump needs to be rebuilt. The bearing can fail before the seal leaks. I usually try the fan rock about every oil change, it only takes a minute and can save a radiator, fan, and maybe more.

If you end up getting a new water pump, there is a serial number break which might affect the parts you need. You can check it out in the online parts catalog.
https://partscatalog.deere.com/jdrc/nav ... ment/66201

[Lavoy]

The impellor is what the seal rides against, so it has to be replaced as well. If you break the housing trying to do it yourself, you will have no core value to purchase a rebuilt.
Not sure where you heard that rebuilding is the way to go, but I used to do it, then II quit, not worth the hassles and potential loss of core value if I break one.
Lavoy

[Kaiverol]

Good to know that impeller is required (helps explain what I saw in video).

Lavoy, don’t you remember the posts for the “water pump on a 1978 450C crawler” from 2009? Ok, so that’s a while ago, but that’s where I got the idea to rebuild myself. If better mechanics than me, such as yourself buy rebuilt, then I am not ashamed to do so and frankly that is a relief. Is the JD dealer my best bet? I also have access to US shipping address now.

Jim, I did take various measurements before potential disassembly beyond the hub and the hub was flush with the shaft. Interesting, but my pump matches a 350 straight with the pulley being separate from the hub. No doubt this is not the original pump.

Earlier today I did think about being able to wiggle the fan blade to assess the state of the pump, but I really wouldn’t have picked up on that before, not having seen a worn out pump until now. Also you have explained why the leak had not necessarily started with such wear right away. No damage caused to rad etc. However, my rad needs some soldering/brazing at the filler cap joint. Thinking about taking it to a rad shop and letting them fix it right.

[Kaiverol]

My water pump is now rebuilt. When I purchased my kit (reasonable price), I asked the dealers parts person (not the regular guys) if they could also do the rebuild for me. The parts person not being 100% sure gave me an estimate and confirmed it with the other employee present of 2.5 hr at their shop rate of over $200 per hr (cdn) add tax (13%). Yikes!

I had other parts being worked on at my machine shop of choice, so I asked if they could do my water pump for me. They were not keen on it, saying they don’t like to do these pumps, worrying about getting the seal in reliably. However, they offered to let me use their press for free.

Today I went in to press the parts. Job took me about 1.5 hr of super slow methodical work. I was careful to follow instructions and press and support at the right points. Even still, I almost made a few mistakes, but caught them in time.

I’m pretty sure I was successful, but we’ll see.