speedseal: problem solved

[snowleopard]

regulars may recall my pleas for help a few weeks ago on raw water pumps not pumping.

in the end it turned out to be a combination of problems and i now have two exhausts cheerfully gushing water /forums/images/icons/smile.gif.

1. the speedseal plates had worn a groove from the friction of the impellers, increasing the clearance at the end of the vanes.

2. the speedseal instructions say only do up the thumbscrews finger tight so you can get them off without tools. this doesn't work as it doesn't produce enough pressure to compress the o-ring seal and it leaves a gap.

3. for good measure i invested in another set of impellers, they did no good on their own but the old ones may have been a little worn.

each of these problems added a few thou to the gap, adding up to the pump being too feeble to overcome the back pressure of the exhaust.

very relieved to find the fixes have worked as the main aged wanted to relieve me of over £400 for new pumps.

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[haim]

it seems that i have a similar problem, my Vovlo MD2B does not water coming out
to the exhaust ,although they are getting into the input,

It seems that the water pump does not have enough power to push in enough water and press against the pressure coming back from the exhaust,

I wnated to understad how did you got the water pump stonger ,as you mentioned that new impler was not the main cure,

Thanks for the help

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[snowleopard]

the impeller had worn a depression in the face of the speedseal, about 3 thou deep. i ground it flat again using wet & dry paper used wet. the paper was laid on a perfectly flat surface (i used a metal plate, glass would also do) and the cover rubbed flat on it, this ensured the surface remained true. i also abraded the face of the pump just enough to ensure it was smooth. i polished both surfaces with very fine paper.

imortant point: the o-ring seal on my pump is in a groove in the pump body. if yours is let into the face of the speedseal plate you have a problem as the groove would get shallower when grinding down the plate.

have you tried re-fitting the original cover plate?

some pumps have a wear plate in the pump body behind the impeller. if yours has this you could try changing it. unfortunately mine is a solid casting so i can't do this - and the pump only comes as a complete assembly!

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[wiggy]

Ifn you dont have a speed seal it may be possible to do as I did and simply turn the pump cover plate around (outside in). Clean the new inside thouroughly and it should work as new.

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