So what else could it be..?

ST840

ST840

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Long story short. My raw water pump leaked and last April was sent to a well known refurb company. Came back and was green (I have a grey yanmar engine ?), but leak was stopped. 3 months later the same pump leaked oil, so under warranty was removed and sent back. Refitted and for 5 months was fine. Then two weeks ago it started leaking water again. So, again removed and sent back under warranty. I got a call from the company saying that some pumps just don't like being fixed!!!!
I argued and today the pump has been delivered back to me, apparently refurbed again as a priority. They say that if it leaks agin then there must be an engine issue.
So, if it leaks what could be causing it to happen if it's not the pump itself??
Ta, not so short after all eh!
 
In no particular order .

Some sort of vibration ?

Is it belt driven or gear driven ? If belt too tight = Stress on the spindle compressing a seal which eventually gives up sooner .

Heat cycles due to its mounting position distorts the seals sooner .

Or the pump housing distorted , out of tolerance so any seals never really gonna work longterm .= new pump needed .

A pic of the leak would help because it could be simply a distorted face plate .Where exactly is the leak on the thing ? Without details it’s difficult to help other than generalisations.
 
Portofino said:
In no particular order .

Some sort of vibration ?

Is it belt driven or gear driven ? If belt too tight = Stress on the spindle compressing a seal which eventually gives up sooner .

Heat cycles due to its mounting position distorts the seals sooner .

Or the pump housing distorted , out of tolerance so any seals never really gonna work longterm .= new pump needed .

A pic of the leak would help because it could be simply a distorted face plate .Where exactly is the leak on the thing ? Without details it’s difficult to help other than generalisations.
Click to expand...
Ok, when I get home I'll take some pics and post them up !
 
slightly confusing, first time after refurb leaked oil (means it's gear driven...) then after second rebuilt leaked seawater. Is that right? doesn't look like a consistent type of failure tbh
 
vas said:
slightly confusing, first time after refurb leaked oil (means it's gear driven...) then after second rebuilt leaked seawater. Is that right? doesn't look like a consistent type of failure tbh
Click to expand...
Yeah that's correct. Water, oil then again water. All in 9 months.
 
Maybe the pump shaft is worn, and fitting seals each time is just patching over the issue.
How much would a new pump be?
 
SC35 said:
Maybe the pump shaft is worn, and fitting seals each time is just patching over the issue.
How much would a new pump be?
Click to expand...
£1k if I could find one. The companies I've seen (not that I've searched hard) have all been out of stock.
 
Phantomfil said:
They are trying to tell you to get a Volvo.
Click to expand...

Volvo's are not immune to randomly sending large bills towards you.
I had to fork out £2650 unexpectedly last season for a Power Control Unit box that decided to walk the plank.
 
Would it a off the self bolt on ? Ie not Yanmar made .
My Yan geny uses a Johnson and the MAN s have jabscos bolted on .

So you skip the proprietary engine maker and go to the pump manufacturers.
 
Where is it springing a leak? As noted a worn shaft will see off new seals sharpish, but unless the refurbishers are idiots they would have either replaced the worn shaft or fitted a wear sleeve. There are rubbish offbrand seals lurking in 'branded' boxes out there, it might be worth asking where they are getting their seals from.
 
penfold said:
Where is it springing a leak? As noted a worn shaft will see off new seals sharpish, but unless the refurbishers are idiots they would have either replaced the worn shaft or fitted a wear sleeve. There are rubbish offbrand seals lurking in 'branded' boxes out there, it might be worth asking where they are getting their seals from.
Click to expand...
The refurb firm is probably the go to firm that most people use. I've asked another couple of companies who advertise the service and they all send them to the same company.
 
I am not familiar with the pump in question...where does the oil come from is it an engine oil way lubricated...
My first guess is that the pump should be primed befor use, if you are just bolting it on and firing up the engine it will possibly shorten the life of the seals considerably running dry.
 
Portofino said:
Would it a off the self bolt on ? Ie not Yanmar made .
My Yan geny uses a Johnson and the MAN s have jabscos bolted on .

So you skip the proprietary engine maker and go to the pump manufacturers.
Click to expand...
How would I know? Is there a cross reference chart for these kind of things??
 
billskip said:
I am not familiar with the pump in question...where does the oil come from is it an engine oil way lubricated...
My first guess is that the pump should be primed befor use, if you are just bolting it on and firing up the engine it will possibly shorten the life of the seals considerably running dry.
Click to expand...
? you may well be correct. I don't remember reading in the manual about the pump needed if priming however. How would that be done? By cranking the engine by hand?
 
From the water side there maybe a place where you can pour water into the system to wet it out, I dont know the layout as for the oil side a few drops ov engine oil around the seal area.....I could of course be totally wrong.....but dry seals will have their edge taken of pretty quick.
 
So is it a 3GM , or what model is it and year, is your boat a single engine . Oh i wonder if they painted it green ,if it was Volvo green did they think it was off a Volvo if so maybe you could get a remake .
 
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