XP 25 freshwater pump problem

Terry Forshier · May 05, 2008, 04:32:34 PM

I have a 1988 C34 with the original engine and 1000 hours. Motoring in today the motor started squawking (like the belt was sticking on a pulley) I shut it down. The motor was not showing hot. Removing the cover I saw that the top pulley that turns the FW cooling pump (as indicated on the owners manual picture) was sticking causing the belt to squawk.
I called tow boat US and was towed in. Upon arriving at the dock I cranked the motor over to be sure it was not froze-up. It turned right over but it was definitely sticking on that pulley and would turn the stop then on and off again. I noticed wet spatter area and smell like antifreeze. The coolant level was OK in the radiator. There was no leakage in the engine compartment. I could also see a small leak in the raw water pump area had caused white salt crystals to form on the engine below the raw water pump..
I have not checked the impeller yet.
Should I start at the impeller or start by calling the mechanic?

Steve McGill · May 05, 2008, 05:01:01 PM

Terry,

The FW Pump is a maintenance item that I have found when it's ready, its goes.
The part can be purchased for about $245-275 at www.marinedieseldirect.com or at marinepartssource.com. I am sure there are other places.

A year ago mine seized up entirely, I required a tow to the nearest marina. I had one shipped to me, it took me about 3 hours to remove old and replace. This included the gasket, nipple, painting the new pump and adding antifreeze and checking for any leaks.

Also check out your raw water pump, may only need a new gasket

Best of luck,

Steve

Ron Hill · May 05, 2008, 07:20:21 PM

Terry : Sounds like your internal water pump just went.
Contact your local Kubota dealer and ask them for a water pump for a B7200 tractor engine and a gasket to go with it. I'll guess it'll be about $100. When you install it use some Hi temp RV caulk, but let the caulk cure a bit before tightening it down - so all of the caulk doesn't squirt out!!
The cause of the failure could be lack of lubrication (old coolant) and or too tight a drive belt! I had to replace mine once a while back. Good Luck.

Stu Jackson · May 05, 2008, 08:12:10 PM

Another "marine" vs Kubota tractor price point issue. Find your Kubota dealer and save a bundle. I recollect that Terry found his Kubota dealer, right in Naples, already. Good luck, Terry, should be a quick fix.

Ken Juul · May 06, 2008, 09:42:59 AM

Terry,
This is off the top of my head, but it seems most raw water pumps have a life of 1000-1500 hours. I had to replace mine due to internal seal failure at about 1200, seems others have about the same experience.

You did not say which brand of raw water pump you have. If you get it apart and find it is something more than a bad gasket/o-ring, a rebuild or replacement should be considered. If it is a Sherwood, rebuilding costs about the same as a new one. Parts availability is also a problem. No experience with the Oberdofer. Do a search on the appropriate pump name, they have been discussed quite often. Tips and places to purchase are listed.

Terry Forshier · May 08, 2008, 04:41:27 PM

This was not the salt water pump but the internal pump that pumps the antifreeze to and from the motor and into the hot water heater. I found one at the Kabota dealer for about $125.00 and put it in. While taking it out I noticed the 3/8 hose had crimped and was probably spraying antifreeze , just a light spray though so not build up in the motor well. I also have found that 3/8 hot water tubing is no longer carried at WM nor at any other place in this area. I was told I could use the antifreeze tubing by the local boat dealer/repair shop where I have service done. The tubing is thicker, black, has an internal webbing and seems pretty durable.
Also when I removed the old pump the cylindrical protrusion where you attach the larger 5/8 inch tubing in the lower right hand quadrant was so corroded it literally broke off in my hand.
The pump mechanism had shifted internally and was out of line on the shaft. I had always thought the belt was severely tight but it had been put on by a diesel mechanic so assumed it was OK. Seemed to have pulled it out of line or internally corroded and broke free. Regardless, I fired it up and it ran like a champ.
When I purchased the boat 2 years ago the PO had run it with a small leak dripping down the side. This has led to the paint deteriorating and the casting for the motor is rusting pretty badly and flaking off. I have just sprayed this with T9 and hoped for the best.
I am now thinking of power spraying and spraying with purple decreaser and repainting this area. Where do I find the paint? Do you think this will work> any tips appreciated.
Terry

Tom Soko · May 08, 2008, 05:03:26 PM

Terry,
You could order the paint from W/U and spend $$$$, or you could go to your local auto paint supply store and ask for GM #286 (Camel). It is an exact match, or at least as exact as my eyes can discern. It comes in convenient spray cans for a few bucks each. Hope this helps.

Ken Juul · May 09, 2008, 06:00:12 AM

Terry I understood your main concern was the internal pump. You got good advice about it, glad the replacement went smoothly.

Your first post also mentioned a small leak from the raw water pump. I was addressing that. If the shaft seals are causing the leak the pump should be repaired or replaced. The leak will only get worse. In the worst case a failure of all the shaft seals in the RW pump can allow sea water to enter the engine. That would not be a good thing.

Ron Hill · May 09, 2008, 06:31:36 PM

Terry : You could have used any 3/8" auto heater hose. The paint color has been written up in the Mainsheet a number of times -- (GM Camel).
Also a simple belt tensioning trick is to place the belt between two fingers. You should not be able to twist it more than 180 degrees, but at least 90 degrees. Found that in the Old Farmers Almanac!!

Stu Jackson · May 10, 2008, 10:54:34 AM

Terry

See: http://c34.org/bbs/index.php/topic,3619.0.html for an alternator belt tensioner source. I bought one, it's great. Like, all of $10!!!

Terry Forshier · May 10, 2008, 11:59:12 AM

I installed the fresh water pump and all is well there. I do still have a leak at the raw water pump. It is not leaking around the housing where the impeller is , it is dripping out of the little slots in the housing where it fastens on to the block. It is back behind the pumping business where the hoses are. I thought it was the gasket there but further inspection,while running, revealed it is coming out of the slot at the bottom of cylindrical housing. There are 2 slots one at the top and one on the bottom. so I assume the post earlier that the pump was leaking in the inner seals may be valid. What else would it be?

Ron Hill · May 10, 2008, 12:29:53 PM

Terry : Right ON!! The water side lip seal is leaking. I'd recommend that you get that lipseal replaced. If not the water will come out of the "weep hole", run down the front of the engine and rust out the oil pan!!

I wrote up a Mainsheet article on replacing the two lip seals in an Oberdoffer. You'll need to replace both lip seals - as to get to the water seal you'll need to remove and then replace the oil seal. If the stainless shaft is older and worn I'd replace it too. I'm sure that you can also find someone to replace it if you don't want to try it yourself.
Call DEPCO (800)445-1656 to get the best price on parts. As I recall you have a 1988 and probably have a Oberdoffer model 202-M15. Good Luck

Terry Forshier · May 12, 2008, 06:43:34 AM

I talked to the DEPCO parts dept this morning and decided to just order the $200 pump complete. Then to check out the old one out and if repairable keep it for a spare. The old one has 1100 hours on it and the PO tried to fix it off and on for years and it looks like it dripped down the side of the block for all those years. I will post again when complete. I have never done much mechanical work and this is giving me a good feeling of accomplishemnt . Terry

Stu Jackson · May 12, 2008, 08:07:05 AM

Good idea, Terry. FWIW, the pump itself generally doesn't go, it's simply the seals. You're doing what I did: get a whole new pump, shaft and seals, and gaskets, so all you have to do is remove the old one and slap the new one in. Keep the old parts, put a new impeller on the old shaft if it's in good shape so you have an instant replacement, and spend some time deciding whether you or a shop will replace the seals on your old pump so you'll have a backup in 10 years when this new one's seals start to go.

Ron Hill · May 12, 2008, 06:05:09 PM

Terry : As Stu mentioned that pump body is nearly "bullet proof" . The only real damage that can be do to it is to score/scratch the inner wall while replacing the lip seals - Or have a worn(groved) face plate.

If you read my pump rebuild article the real "key" is to make a special tool which allows removing those seals a snap. Then you'll have a new pump ready to go. I wouldn't recommend that you install the impeller on the shaft and put it in the extra pump for storage. I keep my regular and Globe impellers "as is" so they don't get stored all "scrunched up" - for years. A few thoughts.