Raw water pump woes

[Leighb]

In early June the engineer who had done our work over the winter noticed a leak from the raw water pump. The pump was removed, new seals and bearings fitted and pump refitted.

Yesterday because of overheating at higher speeds on that engine, a different engineer started his investigation by removing the raw water pump to make certain there was no excessive wear as part of the cause of the overheating.
On removing the pump he found this!!!!

On further dismantling the pump it was found that the other ball race had also lost half of it's balls!

Although unrelated to the overheating what possible reason could there be for new bearings to break up like this? The engine has run for about 55 hours since the bearings were replaced and only around 2400 RPM because of the overheating. Result is I need a new pump as the breakup has caused a lot of scoring internally.

Not happy.

 

[volvopaul]

Looking at the pic I doubt very much new bearings were fitted at all.
There is no way they would fail at 55 hours , I'd be taking the pump back to them .

 

[[2068]]

Were they replaced with Volvo bearings, or just "bearings' ?

 

[Leighb]

Not Volvo. From the local bearing factors in Ipswich.

 

[essexboy]

Were they replaced with Volvo bearings, or just "bearings' ?[/QUOTe

The chances that Volvo makes bearings are the same as the BBC giving fair and unbiased views !

 

[[2068]]

Were they replaced with Volvo bearings, or just "bearings' ?[/QUOTe

The chances that Volvo makes bearings are the same as the BBC giving fair and unbiased views !

Volvo don't make a lot of parts, but they do write the specifications for those parts.
Any part that meets the specification should be fine.
If you buy a part from a random supplier that's the correct size, you are taking pot luck, unless you have examined the specs in detail, and have convinced yourself that the part is as good as or better than the original part.

 

[penberth3]

Volvo don't make a lot of parts, but they do write the specifications for those parts.
Any part that meets the specification should be fine.
If you buy a part from a random supplier that's the correct size, you are taking pot luck, unless you have examined the specs in detail, and have convinced yourself that the part is as good as or better than the original part.

I think you're doing a lot better than "pot luck" if you buy a known brand, SKF, Koyo etc.,

 

[TK Blue MAX]

Volvo were actually owned by SKF if i recall correctly ,

 

[Jim@sea]

I had a faulty water pump (on a forklift) and as a new one was so horrifically expensive the mechanic took it to s specialist pump overhauler. it was reconditioned and fitted, 4 months later it failed. (3 hours work a week) when I complained to the Pump Repairer they said that they told the mechanic that as it had also been repaired previously they could not guarantee the work. Obviously the mechanic did nit tell me that otherwise I would have bought the horribly (but new) pump instead.
Which is why I recently sold a boat with a BMC Diesel Engine as I wanted a spare Pump and I could only find one which had been repaired and was exchange.
In future for such an important part I would only buy new, or if reconditioned ones were available, buy two, one fitted and one spare.

 

[snowbird30ds]

Were they replaced with Volvo bearings, or just "bearings' ?[/QUOTe

The chances that Volvo makes bearings are the same as the BBC giving fair and unbiased views !

Bearing in mind volvo were originally a bearing manufacturer........

I'd be more worried about where are the missing balls, can they get inside the crankcase or were they retrieved?

 

[Leighb]

Worries me also! However most likely they have gone down into the sump where hopefully they won't do much harm??

 

[snowbird30ds]

Can you get a magnetic probe down there at all for a rummage about? I'd prefer them out to chancing it will be ok, a ball bearing between gear teeth will be horribly expensive.

 

[Leighb]

Not sure one could without major dismantling,? The engine has been running for some hours probably after the races started to break up so one hopes any damage would already have occurred if it was going to?

There was no sudden event which triggered the removal of the pump, it was part of a planned investigation of the causes of overheating at high rpm.

 

[dragoon]

Have the bearings failed due to water ingress? If so, was the correct seal, with stainless steel spring used in the pump rebuild? If not, check the used quality parts e.g. SKF which I think are the original parts.

If the balls have gone into the sump - which in theory they should have, then they will be blocked access to the oil system by the strainer.

I'm not sure if the balls are stainless or not - if they are you might not be able to pick them with a magnet in any case.

There is a sump plug on those engines, but it's right underneath and down the centre line.

I would check the other pump. Also compare measurement on shaft sticking out. It's possible to rebuild these pumps with the shaft too far in or out from memory.

 

[dragoon]

On the over heating, have you checked the oil cooler? Mine clog up every few years. I've lost count of how many times I've taken the front off them and cleaned them.

Of late, I've also had issues with the solid water pipes blocking up. The ones from the pump to the oil cooler, but also the heatex to the exhaust bend blocked almost solid.

 

[Boat2016]

Could they have been damaged while fitting?

 

[Leighb]

In the interests of brevity I did not give the full saga of the water pump fitting by the previous engineer.
As I said the pump was removed due to a small leak from the tell tale hole. There was no evidence that it had leaked into the engine, so rear seal was OK. New seals and bearings were collected from Ipswich next morning and the pump was rebuilt by another senior engineer in the firm and then refitted later that morning by the chap who had taken it off. When he started the engine, to his and my dismay it didn't just dribble out, it p***ed out!!!!
So pump removed again and taken back to workshop. He came back that afternoon, somewhat embarrassed, with the rebuilt pump which now had the NEW seals in, apparently his boss when doing it that morning had put the old seals back in!!!! Hardly surprising that it leaked even worse.

What I don't know for certain is whether NEW bearings were also fitted the first or second time or indeed at all. Also assuming it was both times, then they had been removed and refitted twice with possibility for damage perhaps due to rushing the job.

However it is clear to me that their poor practice is responsible for the bearing failure and consequential pump damage. As they have only recently sent me their account for that and some other work, I will be making a deduction when I settle (does this seem fair?)

The damage to the pump body is such that it is not repairable apparently.

Dragoon, thanks for your comments about clogged pipework and oil cooler. The whole raw water system is being flushed with Rydlyme as suggested in reply to my earlier post which will hopefully clear these out.

The other pump has not been disturbed, apart from a new impeller, and does not leak, so I will leave well alone.

Once it is all reassembled we will see if all is well. I will update in due course.

 

[[2068]]

As mentioned above, it's also possible that if the bearings were not positioned correctly on the shaft, you could end up with the shaft end sticking out too much, and large lateral forces applied to the bearings.

 

[dragoon]

In the interests of brevity I did not give the full saga of the water pump fitting by the previous engineer.
As I said the pump was removed due to a small leak from the tell tale hole. There was no evidence that it had leaked into the engine, so rear seal was OK. New seals and bearings were collected from Ipswich next morning and the pump was rebuilt by another senior engineer in the firm and then refitted later that morning by the chap who had taken it off. When he started the engine, to his and my dismay it didn't just dribble out, it p***ed out!!!!
So pump removed again and taken back to workshop. He came back that afternoon, somewhat embarrassed, with the rebuilt pump which now had the NEW seals in, apparently his boss when doing it that morning had put the old seals back in!!!! Hardly surprising that it leaked even worse.

What I don't know for certain is whether NEW bearings were also fitted the first or second time or indeed at all. Also assuming it was both times, then they had been removed and refitted twice with possibility for damage perhaps due to rushing the job.

However it is clear to me that their poor practice is responsible for the bearing failure and consequential pump damage. As they have only recently sent me their account for that and some other work, I will be making a deduction when I settle (does this seem fair?)

The damage to the pump body is such that it is not repairable apparently.

Dragoon, thanks for your comments about clogged pipework and oil cooler. The whole raw water system is being flushed with Rydlyme as suggested in reply to my earlier post which will hopefully clear these out.

The other pump has not been disturbed, apart from a new impeller, and does not leak, so I will leave well alone.

Once it is all reassembled we will see if all is well. I will update in due course.

Blimey, a "senior engineer" shouldn't be reusing seals. I actually don't see how you can - they come out in a right state usually as they are hard to shift. I also don't think there is a rear seal, unless your pumps are different to mine (I think the TMD40's are just smaller than the TAMD40's - same design I would imagine) - from front to back it goes - impeller -> seal -> bearings (x2 on TAMD40s) -> drive coupling

I wonder if they've put the bearings on and off the shaft by applying force to the outer race. When fitting radial bearings, ideally you should use a press to apply constant pressure, but at minimum only the inner race should have force applied to it. If applying pressure to just the outer race, especially with a hammer, you can start to push the whole assembly apart. To my mind the only real options are that they've used dirt cheap bearings, or they've hammered them on and off incorrectly.

It's a shame they've damaged the pump body - I don't believe that will be cheap as they are phosphor bronze I think.

I hope this doesn't sound negative, but I think I'd be demanding payment for the whole thing, and finding another engineer!

It's a shame you're so far away - I have a press in my workshop which I bought 15 years ago, solely for the purpose of stripping and rebuilding my raw water pumps - although it's been used on many other things. It's an easy job if you take your time, and parts are about £20-£30 in total for 2 x bearings and the correct seal. I would say bring it here and I'd help you no problem.

On the Rydlyme, be aware that where there isn't flow already, Rydlyme is unlikely to create flow. So if you have blocked tubes, it's unlikely to clear them. If there is flow it stands a chance. That's my experience of it , but there's no harm in trying. Hopefully it improves things.

They way I cleared the fixed pipes was to take them out and gently knock them with a piece of wood - massive clumps of calcium fell out!

 

[Poignard]

All too often "a senior engineer" means some old geezer that thinks he knows allthere is to know about engineering and has nothing more to learn.