2630 John Deere water coolant pump rebuild

[chickenfriend]

I am in the process of rebuilding the water pump on my 2630 and have been slowed down by one problem.

What I am stuck on is that I cannot obtain the steel tube which goes between the top of the pump to the lower thermostat housing. Seals with o-rings on both ends. John Deere doesn't have it. It is about 2.4" long. The old tube was easy to pull from the water pump housing, even having some play (but not leaking), but the end in the thermostat housing needed some oxy-acet heat and heavy coaxing to be twisted out.

What Deere will direct you to is a tube about half that length, for 50$, and you will need two of them, the other to insert into the thermostat housing. Then you need a short section of rubber hose to go over both of them, secured with two worm gear clamps. So 100$ for these two steel tubes/nipples, plus 10$ for the hose. Need the two fat o-rings, too.

Why is this part obsolete for my tractor? I'd rather have it the way it was originally done. Even if I were to buy an aftermarket pump, looks like those also have the short bushing and so you would still need a second tube at 50$, to insert into the thermostat housing, and the hose piece to join them, plus two hose clamps.

Looking like I will have to have the tube made at a machine shop. I might order stock in stainless, 29mm in diameter, and have the shop turn it down until it fits with a slight interference in both bores.

Another interesting situation is that the seal kit, the seal which gets seated in the housing and the tool to push it in, are not in stock at John Deere. If they were, 50$. Seems like a lot to pay for a seal. However, one parts site on line, while indicating the kit is no longer available, reveals that the two parts are obtainable separately (and at a reasonable price).

Picture of the old and new tubes:

Old tube sticking out of lower thermostat housing before I removed it, above.

Bore for tube in water pump, oring before removal, above.

 

[Tx Jim]

My understanding when consulting the JD 2630 parts catalog is that it shows one needs two(2) R59050 parts to replace the single part & a hose part # R59052 connects both tubes.

 

[Fixingfarmer]

38 dollars and you get a meter of it if order the right size this way and not bother turning it. You can probably add the taper to both ends yourself

 

[chickenfriend]

Thank you for your replies and assistance gentlemen.

Dairy tube of 29mm OD is exactly what I was looking as a starting point. I think 1.5 mm is about the thickness of the stock Deere tube. I also found that SS tube selling on Amazon in 2mm thickness, 500mm in length. Only around 6 thousands would need to come off of it. I have alot in the shop but not a lathe!

Now, I found it odd that the new "shortie tube" Deere sells has a stepped diameter, 1.110" on one half and 1.125" on the other half (you can even see the size step in my first picture, showing as the line in the middle of the tube). The larger end fits better in both the thermostat casting and the pump casting, pretty good in the thermostat housing bore, but with slight play in the water pump housing. The bore in the water pump housing is shorter so there is more tendency for it to rock.

It should have a tiny more diameter to be a slight interference fit . I don't want to have to drive the tube in, but I don't want it to rock, either. As best as I could measure before mangling it, my old tube was about 1.135" diameter. Regardless, I would take the two housings in to make sure the made part will fit well in both.

I have already cleaned both bores using a plumber's brush and a Dremel flap wheel. Most of the corrosion was on the old tube, the machining for the bore holes is still visible after cleaning.

Too bad John Deere didn't originally bore the holes to accept a 29mm tube. I would think threaded pipe could have worked, too.

 

[Jim.ME]

I see there was a break in engine serial numbers and there is a difference in the thermostat housings. Compare the picture Tx Jim posted of the housing and the picture below. Which one do you have? The tube R54809 appears to be available from JD for about $70 and there is a new NOS JD one on eBay for $35 plus shipping, right now. I have had good luck with several purchases from that seller.

 

[Tx Jim]

I see there was a break in engine serial numbers and there is a difference in the thermostat housings. Compare the picture Tx Jim posted of the housing and the picture below. Which one do you have? The tube R54809 appears to be available from JD for about $70 and there is a new NOS JD one on eBay for $35 plus shipping, right now. I have had good luck with several purchases from that seller.

View attachment 169143 View attachment 169144

Congratulations for locating the correct information that I failed to locate. Even the part # for the o-rings is shown that I didn't locate.

 

[Jim.ME]

Congratulations for locating the correct information that I failed to locate. Even the part # for the o-rings is shown that I didn't locate.

No congratulations needed, you have found things I didn't before, big thing is we get the info we find out so others can review all that might apply.

I did a bit of extra digging as I have a couple 4276 engines in machines. I did the water pump on my 450E (1985) and don't remember an issue with the tube; I seem to remember it is like the later one with a hose between two short tubes. And I will be looking at the 2640 (1977) to see which tube arrangement it has, to be ready in case I have to do that water pump.

Edit to add: It appears both my 4276 engines (1977 2640 and a 1985 450E) use the two short tubes and a hose between them. To my knowledge both engines are original, but nothing is ever certain.

 

[chickenfriend]

Thanks for everyone's time to help me.

I have had some private messages, too and I will thank those individuals separately.

My 2630 engine serial number is 204565T. The casting number on the bottom thermostat housing half is R54808.

There does seem to be some variation with the pumps, outlets and pulley hub. Some pumps have a heavy press-on pulley hub, and aftermarket pumps would need their smaller hub pressed-off and the heavy hub pressed on, otherwise I think the fan would not match.

Comparing the two thermostat housing diagrams above, mine looks more like the longish-looking one in the diagram Jim TX posted above, but it is hard for me to tell for sure.

The alternative tube, R54809, which JIm ME found, is shown by one website as being 1.75" long, not 2.4" long like my original. Another website shows the dimensions as "5.88 × 3.5 × 1.13 in". The 1.13" would be correct for the diameter but the other two dimensions are a puzzle! If too long, then not too much trouble to cut it to length and chamfer the end. I did send a message to the eBay seller Jim ME showed, and asked if she would give me a measurement of it.

Were I to go with the two "shortie tubes" and hose strategy, I would probably squish some JB Weld down around the top seam between the tube and the bore, especially on the water pump housing, to keep it from rocking around, but just on the top, because going down more would, of course, ruin the o-ring seal.

As an aside, I noticed that a 21mm Craftsman regular 1/2" drive chromed socket is exactly the same OD diameter as the Deere shortie tube (1.125") and very very close to "shortie tube" length. Could be used in as a "shortie tube" emergency substitute; I don't have a Craftsman deep socket of the same size to compare it to. Flow would be a bit restricted over normal unless the square drive end were opened up, so that's why I say emergency.

 

[Jim.ME]

The casting number R54808 is the same as the part number for the early style housing. A search using the R54808 part number; pictures I find on the web of that housing have that casting number on them.

The later style housing is part number AR71134 and using that part number to search; the pictures I find of that housing have the casting number R59051 on them. The housing on my 1977 2640 (engine serial number 423833) has the R59051 casting number and it has the hose between the housing and water pump.

I have found some of the online measurements to be off, whether caused just by not measuring right or trying to convert a dimension, who knows. I suggest you contact the eBay seller and ask if she will measure its length for you, then you will know for certain. Your serial number is a good bit earlier than mine. It sounds to me like you have the early housing and should use the solid tube. It's up to you.

In a joint where a tube is a slip fit into an O-ring inside a bore there will be some play, the O-ring is the seal and the bit of play in the two bores allows for a bit of misalignment of the two bores.

 

[chickenfriend]

Thank you Jim.ME. Very useful information. That eBay seller is out of the office for the weekend, but I did send her a message.

Going with that part seems the best path for me with as much as I know.

Your comment about the tube needing a little play in the bore is well-taken.

With the play I had on the old tube in the water pump housing, I was quite surprised it was not leaking. Surely, with a new o-ring and new tube, sealing will be fine. Both the lower thermostat housing and the water pump are bolted to the engine and so that keeps the tube in place.

At the end of the thread, I can list my part numbers.

As far as the procedure of removing the pulley hub, I advise heat around the hub collar and a substantial puller like a harmonic balancer puller which uses a yoke and two bolts threaded into the pulley hub. Unfortunately, there is not a divet in the center of the shaft for the puller to center on automatically. Do not try to push the shaft out with a press because the hub may crack when it comes up against the uneven face of the pump housing.

I purchased the bearing assembly from Deere, and the bearings are KOYO, Japan, just like the ones on the old bearing assembly.

While I have a shop manual, I did run across some detailed instruction regarding the seal installation which I will read later.

 

[Jim.ME]

Thank you Jim.ME. Very useful information. That eBay seller is out of the office for the weekend, but I did send her a message.

Going with that part seems the best path for me with as much as I know.

Your comment about the tube needing a little play in the bore is well-taken.

With the play I had on the old tube in the water pump housing, I was quite surprised it was not leaking. Surely, with a new o-ring and new tube, sealing will be fine. Both the lower thermostat housing and the water pump are bolted to the engine and so that keeps the tube in place.

At the end of the thread, I can list my part numbers.

As far as the procedure of removing the pulley hub, I advise heat around the hub collar and a substantial puller like a harmonic balancer puller which uses a yoke and two bolts threaded into the pulley hub. Unfortunately, there is not a divet in the center of the shaft for the puller to center on automatically. Do not try to push the shaft out with a press because the hub may crack when it comes up against the uneven face of the pump housing.

I purchased the bearing assembly from Deere, and the bearings are KOYO, Japan, just like the ones on the old bearing assembly.

While I have a shop manual, I did run across some detailed instruction regarding the seal installation which I will read later.

If you didn't, his is a place I would get the O-rings from JD and not try to match them up.

A press is generally the best way to approach a water pump rebuild, not pullers, unless the manual specifies one. No hammer and punch. Your service manual will give you the step-by-step info. Read the procedure and be sure to gather any measurements needed as you go.

 

[buickanddeere]

iirc a tractor with the factory cab and hot air cab heater. The coolant pump has an inlet for coolant returning from the cab heater ?
Sounds like this application is the bypass line to circulate coolant during warmup . Prior to the thermostat opening.
I wonder if it is feasible to tap a pipe thread into the stat housing port and pipe thread into the coolant pump port ?

 

[Jim.ME]

iirc a tractor with the factory cab and heater. The coolant pump has an inlet for coolant returning from the can heater ?
Sounds like this application is the bypass line to circulate coolant during warmup . Prior to the thermostat opening.
I wonder if it is feasible to tap a pipe thread into the stat housing port and pipe thread into the coolant pump port ?

Looks like you were intending to reply to the JD 3130 coolant heater replacement, not this thread on the 2630 water pump.

 

[chickenfriend]

If you didn't, his is a place I would get the O-rings from JD and not try to match them up.

A press is generally the best way to approach a water pump rebuild, not pullers, unless the manual specifies one. No hammer and punch. Your service manual will give you the step-by-step info. Read the procedure and be sure to gather any measurements needed as you go.

Thanks.

My shop manual, at least in the water pump section, does not show the removal of the pulley/fan hub at all, but a press is shown being used for all the other procedures of disassembly and reassembly.

The press-on pulley hub is quite close to the housing and my press plates will not fit in between. I'll be able to look at that space again when I put things together and check the width; regardless, the cross-beam on my inexpensive press will not allow the pump to be under the press plates, if I had press plates thin enough in the first place.

 

[Jim.ME]

I use a bearing separator and steel cutoffs to block it up to the height I need on my old inexpensive press, a pump won't fit between the cross beams on mine either.

 

[chickenfriend]

I use a bearing separator and steel cutoffs to block it up to the height I need on my old inexpensive press, a pump won't fit between the cross beams on mine either.

Good idea.

 

[chickenfriend]

I'm getting ready to return the shortie tube to the dealer and get my 48$ back, but right now, I am trying to figure out my misstep on the part number, so I am retracing my steps.

So when I went to the water pump page in the John Deere catalogue, there was only one version of tube given: the shortie tube. Thanks to help here on the forum, I am now aware of the place to go for the tube information is the thermostat assembly diagrams, which show the engine serial number split and the two different tubes.

On another but related matter, I ordered an R55405 water pump-to-backplate housing gasket, but they gave me a T20242. The T20242 follows the case outer contour and bolt holes ok, except that it has a punched hole the size of the other bolt holes, over the unused cavity in the housing.

What the heck is the hole for? A different style of pump with a bolt coming through there?

Maybe the T20242 will work fine since it seems the unused cavity/dead space is sealed off regardless from the impeller volute area and any coolant. I may return it if I am still apprehensive about it.

Here is a picture of the T20242. I have outlined the gasket hole not present in the R55405 gasket:

For comparison, here is the R55405 gasket:

 

[Jim.ME]

If there is no matching hole in the back plate the hole in the gasket doesn't matter, coolant can't get out of there as it appears to be a dead cavity in the pump housing.

The hole likely has to do with some having a different pump housing and it may be related to a bypass circuit on those units.

 

[chickenfriend]

Thanks again.

Yes, no matching hole in the back plate, so a hole to no where. Interestingly, a hole on the backplate-to-block gasket matches it.

I could cut-off some superfulous gasket coverning the extended "boot-shaped/Italy "cavity on the T20242, not present on the R55# gasket, since the gasket is free in that area (uncompressed). I would hate for it to chunk off in old age and get stuck somewhere, possibly an unnecessary worry on my part.

 

[Jim.ME]

Thanks again.

Yes, no matching hole in the back plate, so a hole to no where. Interestingly, a hole on the backplate-to-block gasket matches it.

I could cut-off some superfulous gasket coverning the extended "boot-shaped/Italy "cavity on the T20242, not present on the R55# gasket, since the gasket is free in that area (uncompressed). I would hate for it to chunk off in old age and get stuck somewhere, possibly an unnecessary worry on my part.

As long as it is a closed area, don't worry about it. It is not cut out on either one you posted pictures of.