Just installed a new Indigo Thermostat kit and now old water pump does not pump

[sailmakered]

Hey all,

As the title says I installed a new Indigo thermostat system, nice design. While I played with the cooling system, I removed the water pump to check it out. The pump looked pretty rough. I cleaned it up with a brass wire wheel. The grease cup was full but the nipple on the shaft end was broken & no grease was getting to the shaft. The shaft has grooves like a record(remember those??). I can see the shaft hole in the pump body is egged out and there is probably an 1/8" of shaft play. I tried calling MMI on Friday to get help & order a new MMI pump but they must have taken the day off....good on them

I guess my question is why my pump worked fine when it was cruddy but won't now clean. Tom at Indigo gave me some ideas to try. I ran the pump without the cover gasket; flipped the impeller, one end of the vanes are a little rounded; took the new sea strainer out of the system. Nothing changed.

I have some other ideas to get the system back to pre Indigo level. There is a bit more plumbing on the Indigo system & maybe the old pump can't quite make it.

Any tips or tricks you might have would be much appreciated. Is there a good way to bench test the pump?

Thanks
Steve
'78 Catalina 27
V-drive blocked A-4 of unknown vintage

[Marian Claire]

Where are you testing for flow? I would think the best place would be the water pump exit. You can actually prime the pump with that hose disconnected. Have you checked for flow at the thru hull. Dan S/V Marian Claire

[hanleyclifford]

Is this a fresh or RWC system?

[sailmakered]

Where are you testing for flow? I would think the best place would be the water pump exit. You can actually prime the pump with that hose disconnected.

I have but only get some water spitting out & I can feel pulsing with my finger over hole.

Have you checked for flow at the thru hull. Dan S/V Marian Claire

I have gotten plenty of flow from t-hull.

[Marian Claire]

Did you pour some water in the pump exit to prime? You will probable need to close the thru hull as it is likely lower than the pump. Do not ask how much water I poured in my pump before that dawned on me. Start the engine and then open thru hull. FWIW. Dan S/V Marian Claire

[sailmakered]

Did you pour some water in the pump exit to prime? You will probable need to close the thru hull as it is likely lower than the pump. Do not ask how much water I poured in my pump before that dawned on me. Start the engine and then open thru hull. FWIW. Dan S/V Marian Claire

I have poured water into both ends but never closed the sea cock I guess it would drain out. I thought these pumps were self priming.

[Marian Claire]

Do you have this pump? http://www.oberdorfer-pumps.com/Spec...204%20page.pdf When you wire brushed the pump was that external surfaces only? Dan S/V Marian Claire

[smosher]

They are not self priming. I remove the intake hose, lift as high as possible, fill the hose then quickly put back on the thruhull.

This usually works,

Steve

[sailmakered]

Do you have this pump? http://www.oberdorfer-pumps.com/Spec...204%20page.pdf When you wire brushed the pump was that external surfaces only? Dan S/V Marian Claire

yes & the cover gasket surfaces....shinned up nice, no gouges.

[sailmakered]

They are not self priming. I remove the intake hose, lift as high as possible, fill the hose then quickly put back on the thruhull.

This usually works,

Steve

Will give a try & close t-hull until engine is running.

[hanleyclifford]

Impeller pumps are not self priming. What makes them work as a raw water pump is their position below the water line. If the input hose rises above the water line you could have trouble getting a weak pump to work even if you prime from the output side. You may have to cobble a method of priming the input side until your new pump arrives. BTW, 1/8" wobble is huge - I'm surprised it wasn't leaking.

[sailmakered]

Impeller pumps are not self priming. What makes them work as a raw water pump is their position below the water line. If the input hose rises above the water line you could have trouble getting a weak pump to work even if you prime from the output side. You may have to cobble a method of priming the input side until your new pump arrives. BTW, 1/8" wobble is huge - I'm surprised it wasn't leaking.

Seemed a little excessive. It was leaking a little but pumping ok. Just ordered the MMI pump I'm going to head down to the boat & try some of the priming tips. I hope to have good news to report this evening.

Thanks everyone
Steve

[sailmakered]

SUCCESS!!!!!

Put the new impeller in, primed it & all worked. The Indigo system works great. I rode her harder than ever before & the gauge never went above the 135F mark. IR thermometer readings seemed in line as well.

Next is the oil filter & MMI pump installs.

It just never ends....ain't it great!!


Thanks for all the help
Steve

[sastanley]

steve, great follow up..glad to see you got it working.

If you ever feel like posting up a few pictures of your V-drive arrangement in the Cat27 I'd love to see them..I have a C-30 with direct drive as the engine is under the galley.

[sailmakered]

FAILURE!!!

Pump was leaking but pumping. Wind got light when outside long beach breakwater yesterday. Lit her up & overheated. Could maintain 140 in neutral but overheat loaded. Drifted slowly to the slip & just used motor for last minute. Pump is finally dead, mmi pump should ship today. Will post some pix.