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RickDV
08-28-2006, 12:16 PM
My raw water pump went out yesterday. We had been out all day on the boat with no problems and then at the end of the day came some noise and smoke and the engine temp started climbing quickly. Was able to shut it down before temp hit 200.

I'm pretty certain that I lost the bearings on the raw water pump. Local MC dealer has one in stock for $180. I am planning to replace it myself with the help of my son and a friend.

Oh yeah...it's a 1989 Prostar 190 with a 351 Ford.

One question I have is removing the existing pump. We've removed the impeller and there is a bolt behind it that looks like it is attaching the pump to the crank shaft. Anyone know if that is a normal thread or is it reverse thread?

Thanks in advance!
RickDV

TMCNo1
08-28-2006, 12:25 PM
My raw water pump went out yesterday. We had been out all day on the boat with no problems and then at the end of the day came some noise and smoke and the engine temp started climbing quickly. Was able to shut it down before temp hit 200.

I'm pretty certain that I lost the bearings on the raw water pump. Local MC dealer has one in stock for $180. I am planning to replace it myself with the help of my son and a friend.

Oh yeah...it's a 1989 Prostar 190 with a 351 Ford.

One question I have is removing the existing pump. We've removed the impeller and there is a bolt behind it that looks like it is attaching the pump to the cracnk shaft. Anyone know if that is a normal thread or is it reverse threa
Thanks in advance!
RickDV

I wouldn't think you would have to replace the whole pump. Just replace the impellor and coverr gasket, unless the pump had been leaking water from it.

bfinley
08-28-2006, 12:28 PM
Rick,

I have a raw water pump from my 1992 Pro Star 205 with a 351. I replaced it because I was overheating, but it turned out that it wasn't the problem. If you want to buy it, let me know. I'd be happy to send you pictures, etc.

Brandon
brandon_finley@hotmail.com

Maristar210
08-28-2006, 12:28 PM
Rick,

This should help:

http://www.tmcowners.com/teamtalk/showthread.php?t=5996&highlight=water+pump+bearing


Steve

RickDV
08-28-2006, 12:32 PM
I wouldn't think you would have to replace the whole pump. Just replace the impellor and coverr gasket, unless the pump had been leaking water from it.

I started hearing a little bit of noise from the water pump earlier this summer. Sounded like bearings going out. Sound would come and go and I had not heard it lately. After getting the hoses disconnected there is a lot of movement and slop around the bearings so it seems quite certain that they are shot. I am assuming that I should replace the entire pump.

Also, I have been getting more than normal amount of water in the bilge, especially after high-speed barefoot runs. I am guessing that the water pump was contributing to that.

What would you do? I do not profess to be a great mechanic and am open to suggestions.

Thanks,
RickDV

TMCNo1
08-28-2006, 03:31 PM
I started hearing a little bit of noise from the water pump earlier this summer. Sounded like bearings going out. Sound would come and go and I had not heard it lately. After getting the hoses disconnected there is a lot of movement and slop around the bearings so it seems quite certain that they are shot. I am assuming that I should replace the entire pump.

Also, I have been getting more than normal amount of water in the bilge, especially after high-speed barefoot runs. I am guessing that the water pump was contributing to that.

What would you do? I do not profess to be a great mechanic and am open to suggestions.

Thanks,
RickDV


With that info, maybe a new pump in in order!

crozhawk
08-29-2006, 10:11 AM
I'm making the same replacement right now on my 88 PS190. The best deal around I've found is from JA Chamberlain, ...$129 for a new Johnson pump(OE). Mine was leaking water around the seal and dripping on the belt flinging water all over in the engine compartment. Take out your old impeller and keep for a spare and the pump comes off easily ,..3 allen bolts that attach to the harmonic balancer and one allen bolt that attaches to the support arm. Ive found it's easier undo the other 2 bolts that attach the support arm to the engine(timing cover). Your pump is made by Johnson, check ebay, I've done some searching and I don't have a MC dealer very close so I had JA Chamberlain overnight one to me ....total was about $165 with shipping. I also found that you could repair the seal/bearings ..but by the time you've got all the parts and hassle, you might as well just get a new pump. hope this helps

Granite_33
08-29-2006, 10:42 AM
I started hearing a little bit of noise from the water pump earlier this summer. Sounded like bearings going out. Sound would come and go and I had not heard it lately. After getting the hoses disconnected there is a lot of movement and slop around the bearings so it seems quite certain that they are shot. I am assuming that I should replace the entire pump.

Also, I have been getting more than normal amount of water in the bilge, especially after high-speed barefoot runs. I am guessing that the water pump was contributing to that.

What would you do? I do not profess to be a great mechanic and am open to suggestions.

Thanks,
RickDV

When the pump went out on the my 91 Maristar, there were actual metal shavings that dropped into the bilge. The slop was there as well.

The extra water in the bilge may be from a few different places. Either the packing gland around your shaft is worn out, or a leak in the RW pump (these two among many). In the case of my seal going out, water from the pump was getting flung around the inside of the engine box. After taking slalom runs, or anywhere at higher speeds, the inside cover was damp from water leaking from the pump and hitting the pulley. Water was everywhere. If you only see water in the bilge and no signs of leaking from the pump, then your water most likely is coming from somewhere else.

I have to say, though with my pump, the impeller was OK and still pumping water even with the bearings giving out. Engine temps were normal.

RickDV
08-31-2006, 08:45 AM
Replaced the raw water pump yesterday and had it on the water last evening. Everything worked great. Even got my son to do the labor on the pump replacement (he was feeling bad for taking out the prop on an underwater log last week.)

So, new pump, new prop. I'm a happy camper again.

RickDV