How to replace/rebuild the water pump on a GL1000 

The information gathered here was compiled during my experience in replacing the water pump on a 1979 GL1000.  I received a great deal of assistance from people on the list, most notably Jim Hughes, Ray Woolridge, Joey Herring, Frank Marx and a few others.   I also used the Clymer and Helm manuals to complete the repair.  The combination of the two was good and the Helm added technical details (and better pictures), but the Clymer was more descriptive.

My weep hole started weeping coolant in August, at first just a few drops, in the end, much more.  I knew the solution was to rebuild or replace the water pump.  My Honda dealer wanted $115 for the pump, I found that ridiculous so I started looking at rebuild options.  By the way, Western Honda (http://www.westernhonda.com) in Arizona only takes $83 for the pump (January, 2001) and that is much more reasonable.  If you use them, be sure to tell them you're a Classic Wings Club member (account #510) to get the pretty decent discount.  They also offer free shipping on all orders of $100.   Niehaus Cycles (http://www.niehauscycles.com) also offers a discount to CWC members.  Another place you might try is Service Honda (http://www.servicehonda.com).  Their parts book and all pricing info is on the web and they appear to offer about 20% off list.

I am very new to working on my GoldWing and it wasn't without a little bit of fear that I approached the task.  I depend on my Wing to get me back and forth to work and the thought of breaking it beyond reasonable repair was ever-present.  I basically found the job pretty easy.  One of the things I have found with working on this motorcycle is that patience is key.  If you try to force or muscle something, you will probably pay for it in the end.  

Step One
Drain the coolant by removing the drain plug on the bottom of the water pump cover (be sure to take the cap off the radiator) and the oil (remove the filter as well).

Step Two
Remove the fairing.  I have a little bit of experience working with cars and my philosophy (to the extent practical) is to get as much out of the way as possible.  I probably could have gotten away with leaving the fairing on, but taking it off gave me some different angles on things and to my way of thinking (perhaps mostly psychological) made the job easier. The bike sure looks different (almost more appealing) without it.  I have read that if you need to replace the fork seals, take them apart before doing this job, that way, everything is out of the way.

Step Three
Remove the radiator.  This is pretty straight-forward, two bolts at the bottom of the radiator and two more at the top.  In addition, remove the lower radiator hose and remove the engine side of the upper hose.  My bike still had the older clamps, I replaced them with the worm style clamps.  The spring things around the hose are there for heat protection.  I also decided that since I was this far in, I would replace the hoses.  I used GATES #21413 for the top hose and #22038 for the bottom.  Both hoses needed to be trimmed to make them work.  Alternatively, a Daco #70942 can be used to get both the upper and the lower hoses.  I personally wasn't real happy with the way the Daco trimmed up - there seemed to be a bit of 'twist' to the OEM hoses, use your best judgment.  I also had to remove the hose (radiator side) to the coolant recovery tank.  This initially hung up when I tried to remove the radiator.  Disconnect the fan wire too.

Step Four
Remove the water pump cover.  There are four fasteners.  The Clymer indicated that the fasteners were screws - mine had hex-head bolts.  Honda started using hex bolts on later models - it depends on your VIN number.  If you have screws, replace them with bolts.  There are two 6 x 22 hex head and two 6 x 80 hex head.  During the procedure, I actually snapped one of the 6 x 22's and a 6 x 20 replaced it just fine.  If you remove the part of the cover that the lower radiator hose connects to (you don't have to) you will need two additional 6 x 22 hex head bolts.

Step Five
This is the hard part - remove the transmission/oil pump cover on the front of the engine.  There are nine screws that have to come out.  Get out your impact driver and have at it.  The basic problem is that there is a frame cross-member that gets in the way on at least three of the screws.  My impact driver (cheap) has a relatively large head.  I used the #3 Phillips bit.  I worked all right on four of the screws.  I then had to improvise.  I took the Phillips bit and fit it into a 8 mm 1/4" drive socket (don't tell Sears), placed the socket on 1/4" to 3/8" converter and added a 1 1/2" extension.  That worked for two more of the screws.  I was stumped on the other three.  I removed the timing belt covers and gained clearance (perhaps it was nothing more than vision, but I thought it helped).  One of Ray's messages talked about using a wobble extension to get around the cross-member so I headed for Sears to pick one up.  While there, I discovered that Craftsman makes a 3/8" socket with a Phillips tip.  The unique part is that the Phillips tip is relatively long and allowed good clearance on the offending cross-member.  I got two more of the screws that way, one left.  That final screw was a lost cause - a mere circle where there should have been a Phillips head.  Again, following Ray's advice, I took my cold chisel and 32-ounce hammer and started banging away.  My initial thought was to attempt to remake the Phillips connector (through brute force).   As I was pounding on it, as if by magic, the screw came loose (I got lucky).  Of the nine screws that came out, there are two different lengths of that screw, be sure to note which one goes where.  The Helm manual notes this for you, the Clymer manual does not.  It's not a disaster of you don't write it down, it's pretty easy to tell by looking at it.  A tap with a rubber mallet and the front cover was in my hands.  Those Phillips head screws did NOT go back on this bike.  The bolts are sort of strange lengths in that they are 35 and 55 mm respectively.  At my hardware store, they only carried 30 and 50 mm lengths.  I went ahead and purchased the Honda bolts for the GL1100 - they are exactly the right size and worked like an absolute dream compared to the Phillips head screws.

Step 6
If you're going to replace the pump, remove the three screws that attach the water pump to the front engine cover housing.  Tap (Ok, hit it pretty hard) the pump out. 

If you're rebuilding the pump, read on.  Click here to see several photos of the water pump in various states of disassembly.  There are three screws that attach the water pump to the front engine housing cover, loosened them 5 or 6 turns.  The first step in the rebuild is to remove the impeller shaft.  On the backside of the water pump is a c-clip that holds the impeller shaft in, remove the clip.  The impeller shaft ends in a V.  Place a narrow chisel inside the V and hammer out the impeller and shaft.  There is no need to remove the impeller from the shaft.  There is a seal that usually remains inside the impeller.  It is a round piece of white ceramic incased in a round black piece of rubber.  Bumping up to that is a mechanical seal.  These are the CX500 seals that you have to purchase from Honda - part number 19217-657-023 gets you both seals.  Finish removing the three screws that attach the water pump to the housing and remove the water pump.  Stick a screwdriver through the front of the water pump and knock out the bearing on the backside of the pump.  Use a flat chisel from the backside to remove the front bearing and the cover and the pump is essentially apart.  To rebuild the pump, you need to replace the bearings and the seal mentioned above.  The bearings are SKF 6000 2RS JEM.  Gently reassemble the pump.  The order of the pieces goes like this:

1. Impeller on Shaft
2. Ceramic Seal inside impeller
3. Longer spacer that fits over impeller shaft
4. Mechanical seal 
5. Tin cover
6. Bearing
7. Spacer
8. Bearing
9. Circlip

I personally chose to replace the pump, mostly because I was chicken.  Three major factors drove my decision.  First, I like to ride my bike.  I'm braving 20-degree weather in a cold garage so that when it finally hits 40, I can ride.  I don't want to have to tear it apart again because the rebuild didn't work.  Second, the bearings were $11 each and the seal was $28 - a total of $50 for rebuild parts.  The new pump was $80 from Western Honda - to me, it wasn't worth the messing around for $30.  I realize that I live in a small town - one Honda dealer, one bearing supplier - prices are likely a bit higher here than they would have been elsewhere.  Ed Audet mentioned that he got the rebuild parts for closer to $35, so if you're very cost conscious, check around a bit.   He didn't say where he got them.  Finally, my mechanical know-how and my toolbox are somewhat limited.  The fit of the bearings into pump and the fit of the impeller shaft to the bearings is very tight.  I wasn't convinced that given the above limitations that I could fit the thing back together without ruining the bearings.  To my way of thinking, one would have to hammer it back together.  The bearings are rather small and I wasn't sure that I knew how to "hammer" without taking a great chance of ruining the bearings.  Perhaps mechanical know would have made up for lack of a proper tool (Is there a proper tool?).  Or perhaps a proper tool would have made up for a perceived lack of mechanical know-how (Or am I just paranoid?).  Not sure.  I also recognized that given a very limited motorcycle budget, I couldn't afford to buy both the rebuild parts and the new pump - I took the safer path.

A final note on the rebuild - I did have the Honda dealer and the bearing supplier show me what I would have purchased and they matched.  If you choose to take the rebuild route - the part numbers listed are good.

Step 7 - Begin putting it back together
Place two new o-rings on the water pump, put the pump back in the engine housing and put the three screws back in.  The pump is kind of an odd shape and only fits into the housing one way.  The pump should fit into the housing with very little intimidation - certainly not with a hammer.  Test fit the pump into the housing without the o-rings.  You will have to wiggle and cajole a bit, but nothing too intense.  If it hangs up anywhere in particular, use a bit of light sandpaper to clean it up a little bit.  Once you're sure it will fit, use a bit of straight anti-freeze to make the o-rings slippery and gently slide the pump in.

Step 8
Put the transmission cover back on the bike.  Replace all o-rings.  There are six that go in the cylinder block, see the end of this document for a complete list of all o-rings, part numbers and locations.  If you have a Helm manual, take a look at section 6, page 7 for a good picture of exactly where six of these o-rings go.  In addition, replace the seal that is in the front of the main oil pump.  There are two collars that go into the reassembly, they both have o-rings and placement is obvious.  There are also three dowels between the engine and the engine cover.  Placement of these is also obvious - they only fit in certain holes.   On the top right hand side dowel, you need an o-ring, it's a tiny one.   Be sure also to replace the seal on the front of the main oil pump.  If your weep hole is leaking oil, this is why.  The seal comes as part of the K & L kit.

Step 9
Replace the water pump cover, radiator, hoses, oil filter and drain plug.  Fill with water and oil.

Step 10
Start it up, flush the coolant through a few times to make sure that all the old anti-freeze is out, replace with a good, silicate-free coolant - I used Dex-Cool.  If you use this it's really important to flush the system well.

Step 11
No leaks, no drips?  Put the fairing back on (or not) and head on out for a ride.

Notes

• Ray mentioned to use anti-seize on the bolts that secure the engine cover housing.   

• The GL1100 bolts worked great and my 1/4" tools got right on them in spite of the frame cross-member so I highly recommend the switch.  

• When putting it back together, watch the neutral switch wire, the first time I put the cover back on, I didn't and wound up taking the cover back off - the wire was between the cover and the case..

• I flushed the system real good and used Dex-Cool coolant.  It is silicate free and a pretty orange color.  Seemed to work OK.  If you have kiddies - put it up high - it looks just like orange Kool-Aid.

• The K & L Seal Kit came with 10 O-rings, I could only find 9 of them.  There are six that I found that go into the case, three with the water pump.  You may only use two of the water pump ones if you don't take off the front cover of the water pump cover.  You don't have to take it off.  I could not find the location of the 10th o-ring.  It's a 13 x 2.5 and after scouring the fiche looking for any instance of a 13 x 2.5 o-ring, the only one I could find was one that went on a part called the oil tube.  I never did find that.

• It was a real pain to get the transmission cover gasket off - I used a razor blade, a gasket scraper and spray gasket remover.

• I am not very experienced with working on the bike and once I got those #$%# Phillips head screws out, it was really an easy job.  If you're at all mechanically inclined and have a measure of self-confidence, you should be all right.

• I did this job sort of one piece at a time over the course of a few months - we had a cold winter and I wasn't all that excited about working on a cold garage floor - couldn't ride anyway.  Now that I have hex heads in place of the Phillips head screws, I believe the job could be completed (assuming you have all the parts) in four to six hours.  Actually, when I took it apart the second time (see below), I had everything out and back in again in two hours.

• The front part of the bike is pretty well torn down during this procedure and things are pretty accessible.  It seemed like an ideal opportunity to replace the timing belts, so I did.  That job was pretty simple as well (took about 10 minutes), especially with the radiator removed.  There were several descriptions of how to replace the belts that I read from time to time.  All of them talked about the left (as you face it) cam jumping - it does.  That didn't appear to be a problem - no need to try and hold it or anything like that - just let the thing jump.  Mine moved about 1/4 turn clockwise.  Put a wrench on it and spin it back (counter-clockwise) to put the new belt on.  When putting that belt back on, an extra pair of hands was helpful to hold the offending cam in place.

• Again, because the front part of the bike is torn down, you might consider changing the thermostat while you're in there,... just because you're in there. The one challenge with replacing the thermostat is it is easy to cock it off center, and cause the gooseneck not to seal. A pretty small crack can sneak by you until you start putting coolant in, and continue to put coolant in . . . 
  
• The old water pump has a rather large set of plastic impellers.  The new pump has a much smaller set of metal impellers.
  

• My bike fired right up after all was done and all systems appeared to be working, thermostat and fan included.

• I had some problems getting this particular job buttoned up.  First time done, after about a week, a pinched o-ring reared it's ugly head and I took it apart again.  Next time together, 3rd gear didn't work.  It's together again, we'll see how it turns out this time.

• The water pump cover is actually two pieces.  If you remove the top piece it's a lot easier to replace the radiator because you don't have to mess with the lower radiator hose.

• Using the GL1100 bolts on the transmission cover allowed me to remove the transmission cover without having to remove the radiator.  This saved a tremendous amount of time when doing the job again (and again . . . and again)

 Parts List

1. 1 K & L Seal Kit, K & L part number 15-4340 - has all the necessary o-rings and gaskets - see note above - alternatively, the individual components of this kit are listed below.

2. 1 Water Pump, Honda part number 19200-371-000 - there are several part numbers for this as the pump covers several years and even models (non-GoldWings too) of bikes.

3. If replacing the timing belts, Honda part number 14400-679-003 or 14400-679-004 are about $30 each (March, 2001) from Service Honda (http://www.servicehonda.com)

To rebuild the water pump, skip the water pump and buy these parts instead:

• Seal from a Honda CX500 Turbo, part number 19217-657-023

• 2 SKF 6000 2RS JEM bearings - get at a bearing supplier

Here is the list of o-rings, part numbers and relative locations of each o-ring.  This is essentially a list of parts in the K&L water pump seal kit.   There are also some miscellaneous things listed - I made several trips to the stores and this list may save you a few.  All part numbers are Honda part numbers.

Tools I Used

• 1/4" and 3/8" metric sockets - not deep wells
• Various lengths of socket extensions
• Torque wrenches - inch and foot pounds if you're serious about torque
• Metric box and closed-end wrenches
• Hand impact driver for Phillips head screws
• Phillips head tipped socket - against the advice of Sears, I used it with the impact driver
• Flat-Head and Phillips head screwdrivers
• Hammer - 32 oz. worked well
• Rubber Mallet
• Chisel
• Gasket Scraper
• Spray gasket remover - careful with the stuff . . .

If you have questions, email me - I'm not a real authority, but I am (now) experienced.  Scott Finn - finns@centurytel.net

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