Cautionary tale - impellors

[longjohnsilver]

During the summer my engine overheated due to weed in the raw water strainer, all seemed ok afterwards but decided to check the impellor. New water pump from about 2 yrs ago, one of the screws on the cover was dacayed so I couldn't easily get the cover off. However took the pump off and peered in through the inlet and outlet ports and the impellor looked fine.

Put it back on, engine has run at normal temps since. Having chatted in the pub on Friday nite to a few boating mates we all agreed that we'd never come across a damaged impellor in any sort of engine. This reminded me of the job to remove the seized screw from the pump so trotted off down to the boat on Saturday, took it out for a run, engine cooling all looked ok, took off pump and had to file off damaged screw and hacksaw off one other which had seized. Cover came off to reveal impellor with at least 5 of the blades only just hanging on by a thread, breathed a sigh of relief and changed it for one of the many spares I keep on board. Luckily also have a spare pump so replacing the damaged screws was no problem, greased everything up and all seemed ok.

A real lesson to me not to assume that something is ok when I really knew that it should have been checked properly after the initial problem and not to put off maintenance cos of some other difficulty. Could have caused a big problem, was lucky this time.

Why is it that getting to the so###g pump is always so awkward, specially for a tall fat bugger like me ;-((

 

[Col]

You could change it for one of thoses Quick change jobbies, with the knurled knobs to undo. Less likely to give probs I would say, but never used them myself. Come to think of it, never had problems stripping pump before

<A target="_blank" HREF=http://www.arweb.co.uk/argallery/colspics> Cols Picture Album</A>

 

[DepSol]

Always carry a can of T9 with you, gets seized nuts off quite quickly or if it is really stuck let it soak over night.

better safe than sorry.

Dom

2003 is going to be a good year for me

 

[longjohnsilver]

Wouldn't have worked here Dom the head of the screw was totally perished! And the one that was stuck was starting to disintegrate with the force from the screwdriver!

 

[jimi]

Speedseal

Thoroughly recommend!
<A target="_blank" HREF=http://www.speedseal.com>http://www.speedseal.com</A>

if you get one get some spare knurled screws , easy to drop into bilges with oily fingers when boat bounces about!

<P ID="edit"><FONT SIZE=-1>Edited by jimi on 20/01/2003 17:10 (server time).</FONT></P>

 

[longjohnsilver]

Yes have seen those advertised, has anyone any experience of them?

 

[Duncan_Hamble]

I change mine every year regardless - I've got an outboard and this requires the gearcase to be removed, however, the potential damage / injury that would occur should the engine overheat and fail makes the extra £30 on the service well worthwhile.

 

[Col]

Re: Speedseal

That's the ones!
They seem a good idea, but as I said, no personal expierence.

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[SteveJ]

I personally would replace the impellor every season. the engineers should at least check this item on a service. it is good practice to check the impellor after the weed has blocked the strainer, after all in most cases it is only 6/8 screws and no more than 1/2 hr to check it out on most boats.

 

[ccscott49]

Marine engines are specially designed, so only emaciated drawfs with double joints (a bit llike gollum in lord of the rings) are capable of working on them. especially getting at impellors, I had a look at a few engines at the boat show, they still put the water pumps in inaccessible places, mentioned it to a few of them, just got blank stares back, pillocks!

 

[ccscott49]

I've got them on both my engines, excellent bit of kit, no gaskets to worry about, I also carry three spare knobs and six "O" rings, just in case.

 

[neale]

If your engine/s is/are under warrenty, check with your main dealer service agent before changing the pump cover. I was informed by a Volvo agent that putting non standard impeller covers on a pair of KAD44's could have affected the warrenty.

 

[Bejasus]

"I also carry three spare knobs"

having seen the New Years pics, I can only suggest you be more careful who you invite on board............../forums/images/icons/laugh.gif

<A target="_blank" HREF=http://www.arweb.co.uk/argallery/h00>http://www.arweb.co.uk/argallery/h00</A>

 

[kingfisher]

Speedseal:got one

I got one on my Volvo 2001. Works a charm. No need to buy seals every time you open the cover. And by now you know that you have to check it at least once, but also every time that your engine has run dry (clogged weed filter etc..)

I'm not running the risk of losing my engine for cause of a 5£ part. So I chuck the impellor every year. It's a five minute job, no tools needed. Quick inspection: two minutes.

The whole thing about engine maintenance: if it's easy to get at, it will be serviced. Case in point your impellor.

So yes, worth it. Could be a bit cheaper. But the brass shine looks ever so great with the Volvo green

Group of people on the pontoon: skipper is the one with the toolbox.
http://sirocco31.tripod.com

 

[ccscott49]

Those pictures will come back to haunt me, I'm sure! But I am careful who I invite! They've got to be as nutty as I am! I should have said knurled knob/bolts, the mind boggles!!

 

[dickh]

I fitted the Speed Seal about 4 years ago - very quick to change the impellor, I keep a spare impellor and cheap long nosed pliers nearby so it can usually be done easily in under a minute.
My pump is at the front of the engine and easy to get at, had to change it when I wanted a quick getaway to catch the tide & forgot to turn on the seacock, after 2 minutes thought the engine was noisy, suddenly remembered, stopped the engine, drifted on the tide towards the sandbank, got it changed v quickly.
My advise is to get one.

dickh
I'd rather be sailing... /forums/images/icons/smile.gif

 

[ccscott49]

By the way, I modified a pair of circlip pliers, by heating and bending the long noses, then bending the pins to face each other, to extract impellors, that was before I bought proper jabsco impellor pullers, they worked a treat, both actually! I've also used slip joint pliers to do the job, depends where your pump is fitted.