Alpha I Water Pump Question

a1nowell · Sep 4, 2010

When repbuilding the outdrive water pump does it make a difference what direction the impeller fans/blades are angled in inside the pump housing? Also I just took mine apart since the boat overheated. Impeller appears fine but the plastic tube was melted.
Any thoughts?

wanna-be · Sep 4, 2010

Re: Alpha I Water Pump Question

since it over heated, id recommend you buy a water pump kit and replace everything. assumign pump has a plastic body. if the impeller is set and stiff, replace it. should have some bounce and the direction of blade is very important...they bend counter-clockwise. be sure and replace the oring around the oil passage or u'll get an oil leak

Bifflefan · Sep 4, 2010

Re: Alpha I Water Pump Question

Impellers are self correcting in these drives.

If the tube is melted you need to replace it. I believe it is more for alignment than anything else but I may be wrong.
Does it run hot on the hose? Or just in the water?

a1nowell · Sep 4, 2010

Re: Alpha I Water Pump Question

I am rebuilding and do have a pump kit. I am just baffeled as to why it would get hot enough to melt the plastic tube yet the impeller is in tact and soft and plyable.

When you say the impeller blade are to be counter clockwise is that looking from the top of the pump?

Bifflefan · Sep 4, 2010

Re: Alpha I Water Pump Question

a1nowell said:
When you say the impeller blade are to be counter clockwise is that looking from the top of the pump?

Read the instructions in the kit, you-tube it.
The impeller is self correcting so its not a real big deal to do it wrong (Just dont leave it wrong for a long period of time). If memory serves, you put the impeller on the shaft, put on the upper cover and turn the shaft clockwise (looking from the top) to seat it in the housing.
Use some grease on the new impeller to make it easier to get in.

Dont run it in a tank, unless you have a really big one that can cover the ventilation plate, use a hose.

dubs283 · Sep 4, 2010

Re: Alpha I Water Pump Question

the plastic tube is for guiding the water passage tube from the upper into the top of the pump when reassembling the drive halves

since it is melted, at some point there was not sufficeint water coming out the exhaust and the hot exhuast gases melted the tube

be sure to check the water passage tube at the bell housing for kinks and inspect the oil cooler on the engine for blockage - weeds/debris

also, if this is an Alpha One with the plastic housing, it is a good idea to replace the pump base assy and gasket/o-ring at this time

when installing the top pump housing over the impeller, rotate the driveshaft clockwise, it always turns this direction

MrSand41 · Sep 4, 2010

Re: Alpha I Water Pump Question

Also how much of the impeller did you find?
If you can't find most of it in the pump it might of made it farther up the line and got stuck somewhere.
The impeller should right itself but i put them into the upper housing with a counter clockwise twist and slide it down onto the shaft and make sure to hit the pin or wedge.
The plastic tube is for alignment of the water tube.

a1nowell · Sep 4, 2010

Re: Alpha I Water Pump Question

Mr Sand41,
As I stated earlier, the impeller is intact no missing parts, soft, plyable etc. That is why I asked about direction of the blades.

MrSand41 · Sep 4, 2010

Re: Alpha I Water Pump Question

a1nowell said:
Mr Sand41,
As I stated earlier, the impeller is intact no missing parts, soft, plyable etc. That is why I asked about direction of the blades.

My bad, I was thinking as if you changed out a pump and couldn't get it to cool down yet after a pump change.:redface:

moparmatt · Sep 4, 2010

Re: Alpha I Water Pump Question

I am also getting ready to change mine tomorrow morning on a alpha 1 gen 1. Is there step by step directions for this process somewhere? The directions I got with the kit are horrible !

dubs283 · Sep 4, 2010

Re: Alpha I Water Pump Question

try youtube as suggested in an earlier post

also, if you have a question concerning your boat, start a new thread, its less confusing

Alpha I Water Pump Question

Chief Petty Officer

Petty Officer 3rd Class

Commander

Chief Petty Officer

Commander

Vice Admiral

Recruit

Chief Petty Officer

Recruit

Seaman Apprentice

Vice Admiral