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Circulation pump failure
Posted: Mon Jan 27, 2014 5:54 pm
by srokag44
I have read numerous times on forums that circulation pumps rarely fail... so sure enough mine did. I had noticed some squealing and wobble for the past couple months and knew it was only a matter of time. Well I was out cruising along this weekend after having the bottom cleaned and the boat was running great (18 knots at 3200 rpm). I noticed the temperature gauge on the stbd engine fluctuating around like crazy and immediately knew what happened. Went down, pulled the engine hatch and it was like a sauna steam room down there! The circulation pump bearing had completely failed and water was spraying all over. Shut it down and dried everything off and got it back to the dock on one motor.
Spent about 2 hours removing the raw water pump, alternator belt, thermostat housing, hoses, u-cooler, and eventually the circulation pump. The U-cooler is one of the older models that has the water outlet to the thermostat at 90 degrees to the oil nuts. (Like 97555 here:
http://www.mrcool.us/97464-crusader-heat-exchanger.html)
The previous owner used a long line of hose coiled in a circle and a 90 degree elbow to make the connection between the thermostat and the u-cooler.

- IMG_2721 (480x640).jpg (196.04 KiB) Viewed 6825 times
I don't think the proper formed hose (
http://www.marinepartssource.com/newdet ... fgno=97861) is going to fit because it is meant for the U-cooler with the 45 degree outlet.
Anyone run into this problem already? I'd like to find the correct formed hose for this to eliminate unnecessary fittings, hose clamps, leak points, and clutter.
Re: Circulation pump failure
Posted: Mon Jan 27, 2014 6:08 pm
by Stripermann2
In the picture, you have shown, a raw water pump and not the circulation pump...so the R/W pump failed?
Re: Circulation pump failure
Posted: Mon Jan 27, 2014 6:47 pm
by srokag44
No no, sorry the picture was just supposed to be of the terrible hose and elbow. The raw water pump is fine... I just rebuilt it a few months ago. The circulation pump is what failed.
Re: Circulation pump failure
Posted: Wed Jan 29, 2014 3:22 pm
by srokag44
Here's what the circulation pump looked like. A lot of corrosion on the impeller. Haven't taken it all the way apart yet but I'm sure what is left of the bearing looks similar.

- IMG_2724 (640x480).jpg (204.13 KiB) Viewed 6769 times
And here is what my U-cooler looks like. The water outlet to the thermostat comes off at 90 degrees instead of 45.

- IMG_2723 (640x480).jpg (218.75 KiB) Viewed 6769 times
How was this supposed to be plumbed to the thermostat? So I don't have to do something like this:

- IMG_2051.JPG (225.01 KiB) Viewed 6769 times
Re: Circulation pump failure
Posted: Wed Jan 29, 2014 3:54 pm
by mikeandanne
what cooler is on the other engine as the raw water cooling system for the 454 model 350 shows the cooler as having the 45 outlet to the thermo with the formed hose you mentioned-----have a look at this ,maybe you already have seen this but anyway I hope this works----Mike
http://www.marinepartssource.com/crusad ... 07dp32.gif
Re: Circulation pump failure
Posted: Wed Jan 29, 2014 4:19 pm
by srokag44
The one on my other engine has the outlet at 45 degrees like the drawing because I replaced it about a year ago. I could do the same for this one but for $300+ I would rather re-use it. I can't seem to find any information on where these 90 degree outlet versions were used.
Re: Circulation pump failure
Posted: Wed Jan 29, 2014 5:27 pm
by mikeandanne
I hear ya---I have much the same issue as can't get original moulded hose so have to get inventive---maybe a 45 degree 1"1/4 plumbing fitting and a couple of pieces of the hose you already have will get you to the thermo housing inlet---Mike
Re: Circulation pump failure
Posted: Wed Jan 29, 2014 5:33 pm
by srokag44
Yeah I like to minimize failure points (extra hoses, fittings, and clamps) but it looks like I have no choice here. I guess I will just use a big loop like what has been on there.
Re: Circulation pump failure
Posted: Wed Jan 29, 2014 9:07 pm
by paskyhawk
I had the circulation pump go on my Chrysler 360 (1979 36 Tri) last summer, it was still pumping but water all over the place. I got an omnidirectional marine pump on eBay for about $100 (well two because we know everything happens in pairs). Toughest part of the job was cleaning up the mounting surface from the old gasket.
Rich M
Buffalo, NY
Re: Circulation pump failure
Posted: Thu Jan 30, 2014 4:16 pm
by srokag44
Anyone know where I can get a replacement circulation pump pulley? Will any big block short pump v-belt pulley work?
Re: Circulation pump failure
Posted: Thu Jan 30, 2014 4:24 pm
by Stripermann2
Most likely it will. But make sure the pulley diameter and offset is the same or very close. We are talking about the circulation pulley right?
http://www.jmsonline.net/crusader-pulle ... OgodBigAVg
Re: Circulation pump failure
Posted: Wed Feb 05, 2014 10:51 am
by srokag44
Just as an FYI for anyone else who runs into this: I couldn't find a replacement for circulation pump pulley 20114 so I ordered R065049. The diameter of this pulley though is larger so it doesn't fit. I still haven't been able to find a replacement for the 20114 pulley. I repaired my old one as best as possible and re-used it.
Also, I would like to speak to the Crusader engineer who though the oil and transmission line connections on the U-cooler were in serviceable locations. I would also like to speak to the Trojan engineer who decided the engine room hatch should stop just short of the front of the engine.
Re: Circulation pump failure
Posted: Wed Feb 05, 2014 11:08 am
by mikeandanne
Check out Summit racing for water pump pulleys,we used to get all sorts of specific pulleys from them,so long as you know the diam etc it is worth a try,I can't imagine there are marine specific pulleys but I guess you never know--- Mike
Re: Circulation pump failure
Posted: Wed Feb 05, 2014 12:07 pm
by prowlersfish
You may be able to find a GM number on the pulley