KAD sea water pump rebuild

[Hangie]

Hi,

Anyone could recommend someone to do sea water pump rebuild/seals change ?

Pump is already out so just work on pump needed

I’m looking in Portsmouth/Chichester or penton hook area.

would try myself but don’t have press to remove shaft or tool to push seals in.
Unless anyone go good DIY might be better to give to pro.

Thanks!

 

[oldgit]

DIY.
If you do not need Facing Plate and shaft, kits from £35, if you need everything inc new impellor £ 130.00.
Those on tight budget might have been known to simply reverse that facing plate, lettering in the face will make no difference at all to the pump flow.
A circlip remover will make life easier but those of us who can never find our pair seem to manage.
The bearings can be removed gently with anything you have to hand and driven back in with a perfectly ordinary socket the correct diameter to go on the outer part of the race.

Worn shaft with grooves ? when fitting new seals just ensure rubber on replacement is on unworn part of shaft, a couple of mm either way will do the job.
This of course is only a emergency temporary repair and it might need doing properly in 5 years time. ?

 

[Hangie]

Pump was just slightly dripping on water side. Beside that looks like in not bad shape.

Seems I'm missing only circlip remover and potentially socket matching ext diameter of bearings.
Will give it a go next weekend as it will be bit chilly for work outside.

Never heard about trick with rotating front plate - that is a proper recycling by doubling the lifespan!
In my case I think it will be just seal + fresh paint but will see.

Thanks!

 

[Boaty_Pete]

Just a quick word of caution, when I did my seawater pump (different penta engine) I wasn't fully prepared for the amount of spacers and the spring etc. We had to use a press as hammering failed, and in the distraction lost the order of parts. Then to add insult to injury, the available schematics disagreed with my particular pump and were showing things in different order.
I got it done (6yrs ago, so all good) but forewarned may help you.

 

[Hangie]

Thanks for extra warning. For me personally springs are the worst ones when you need to put back together.

My pump seems to be exactly as this one

. No springs! 2 seals, 2 bearings, o-ring and plastic spacer.
I'm just worried about that hammering might not work - but at least will know at the beginning that I need better tooling.

BTW this guy (Teds Marine Repair) got some very good videos on engines with good explanation and attention to details and proper workmanship - Now instead of having 30 extra mins of sleep, I know how to time fuel pump, but hopefully will never need to use that knowledge.

 

[jon and michie]

Pump was just slightly dripping on water side. Beside that looks like in not bad shape.

That is generally just the Seal which is an easy fix

 

[oldgit]

Seem to recall with the early 40/41 series, replacing the outer seal with pump in situ on the engine.
This stops that tell tale weep from rear of impellor casting , usually resulting in a rusty stain .

Have always assumed the gap was there assist in preventing leaking cooling water travelling along shaft into lubricating oil ?
Have frequently found after purchase of boat that the outer plate has considerable wear and previous owner has long ago reversed the flipping thing.

 

[jon and michie]

Seem to recall with the early 40/41 series, replacing the outer seal with pump in situ on the engine.
This stops that tell tale weep from rear of impellor casting , usually resulting in a rusty stain .

Have always assumed the gap was there assist in preventing leaking cooling water travelling along shaft into lubricating oil ?
Have frequently found after purchase of boat that the outer plate has considerable wear and previous owner has long ago reversed the flipping thing.

Yep - I did mine in situ with the boat in the water.

 

[Hangie]

Not sure if I'm following.

Are you saying you replaced the seal, which is on the shaft without removing the shaft ?
How did you pull it out ?


The design is quite clever as both water and oil seals are air gapped.

|----|-|----

Going from left to right:

Outside plate with screws.
Place for impeller pumping water
Water seal
Air gap
Oil seal
Shaft connecting back to the engine lubricated with oil

In this way if even both seals will leak water would not get into the engine, but both would end up in the bilge.

 

[oldgit]

For the skipper in a hurry
Remove facing plate and then impellor.
The seal retaining the raw water can easily be seen at the rear of the chamber
The seal can be pulled out with care using any piece of metal rod with a pointed end bent into hook, without damage to the shaft.
I used an old bradle and with luck the seal can be teased out.

Refittting with dab of grease is quick and simple.
Finding a socket that will accomodate the shaft is the problem. Poss a 1/2" drive might be OK.
20 mins at most.