Raw water intake blocked, impeiier cooked!! KAD 32

[Volvo KAD 32 tfft]

I got a piece of rag drawn into my raw water intake, by the time the buzzer was going off the engine was smelling really hot and showing 100 on the temp, i stopped straight away and got towed back, the impeller had disintegrated with just the core left,
I replaced it but there is now a considerable reduction in flow of raw water, so I am guessing the broken fins of the impeller are blocking the flow, has anyone got any ideas where to look before i take off all the hoses, oil cooler, heat exchanger, and charge air cooler?
does the raw water go to the oil cooler before or after the charge air cooler, thanks.

 

[omega2]

follow the pipework from intake to pump then pump to the system, I suspect the charge air will be the first in line, and will likely be full of broken rubber bits.

 

[A_8]

The oil cooler might be the first stop however before the bits get there they should have been caught by the raw water filter. Could parts of the rag be sitting in the piping before the pump, why not flush the system backwards from the pump and out.

 

[volvopaul]

Oil cooler is first place in the flow but the exhaust gasses blow bits backwards which when you inspect a new impeller get sucked up into the cam plate blocking the inlet flow , so check both ways.

 

[omega2]

I am sooooo glad I have a FORD!!!!!

 

[Volvo KAD 32 tfft]

Oil cooler is first place in the flow but the exhaust gasses blow bits backwards which when you inspect a new impeller get sucked up into the cam plate blocking the inlet flow , so check both ways.

Thanks for the advice Paul, when i removed what was left of the impeller, i looked inside the pump and was able to stick my finger into inlet and outlet holes but dont recall seeing a cam plate? am i looking in the wrong place?

 

[neale]

On a kad32 the impeller bits should end up in the strainer. They can't go further forward. Any bit that went backwards would normally get drawn into the new impeller and damage it. If it is a kad on an out drive how did something get sucked into the pipe work? Should have stopped on the outside of the water intake. Have you checked that the water intake is completely clear?

 

[Momac]

On a kad32 the impeller bits should end up in the strainer. They can't go further forward. Any bit that went backwards would normally get drawn into the new impeller and damage it. If it is a kad on an out drive how did something get sucked into the pipe work? Should have stopped on the outside of the water intake. Have you checked that the water intake is completely clear?

I bet its on shafts.

 

[AllanG]

I bet its on shafts.

Yep, the OP has a Nimbus 27, which is shaft driven.

 

[Volvo KAD 32 tfft]

Oil cooler is first place in the flow but the exhaust gasses blow bits backwards which when you inspect a new impeller get sucked up into the cam plate blocking the inlet flow , so check both ways.

Spot on Paul, all the bits had gone back down the sea cock side of the pump, Job done! many thanks.

 

[Volvo KAD 32 tfft]

Yep, the OP has a Nimbus 27, which is shaft driven.

Yep

 

[Volvo KAD 32 tfft]

On a kad32 the impeller bits should end up in the strainer. They can't go further forward. Any bit that went backwards would normally get drawn into the new impeller and damage it. If it is a kad on an out drive how did something get sucked into the pipe work? Should have stopped on the outside of the water intake. Have you checked that the water intake is completely clear?

On shaft so no strainer between pump and oil cooler ( there is now) many thanks for your input

 

[Volvo KAD 32 tfft]

I am sooooo glad I have a FORD!!!!!

Thank you for your informative and helpful reply, you are very welcome to your Ford, do you suffer from penis envy also? or is your envy confined to Volvo engines only.

 

[oldgit]

Think Omegas reply was intended to be humourous and that all engines suffer at some time or other from various maladies.
Basically the Ford based large capacity engines tend to be a bit basic and agricultural in their marinisation and are more frequently used for commercial applications. Volvos,designed from scratch to provide high outputs from small blocks are mainly found in boats for leisure use and tend to be a tiny bit more complicated,both turbo and supercharger, and possibly somewhat more fragile ?.
The KAD 32 produces near 200Hp from 2.5Litres @ 3900 rpm, my M135 produces 135 (ish ask Latestarter) Hp from 6 Litres @ 2600 rpm.
Its horses for courses..

 

[omega2]

Thank you for your informative and helpful reply, you are very welcome to your Ford, do you suffer from penis envy also? or is your envy confined to Volvo engines only.

Sorry no offence intended! as Old Git says we dinosaurs re not used to sophistication consequently we tend to be ------, not seen many dicks lately most are still on the HARD!!

 

[Volvo KAD 32 tfft]

Think Omegas reply was intended to be humourous

as was mine, nothing wrong with a bit of banter,

 

[Volvo KAD 32 tfft]

Sorry no offence intended!
None taken, just rolling with the banter, regards.

 

[oldgit]

None taken, just rolling with the banter, regards.

Did hear the KAD 32 came with free set of ear muffs to lessen the racket coming from the supercharger, a face mask to prevent the inhalation of belt dust and a guide to lessen the effects of Raynaud's syndrome.

 

[wongaero]

On shaft so no strainer between pump and oil cooler ( there is now) many thanks for your input

Did you remember to position the new strainer so that, if you've recently run the engine, it overflows through the alternator when you take the top off, as on the standard outdrive KAD32?

 

[petem]

Did hear the KAD 32 came with free set of ear muffs to lessen the racket coming from the supercharger, a face mask to prevent the inhalation of belt dust and a guide to lessen the effects of Raynaud's syndrome.

Running at 9kts through Portsmouth harbour meant that the supercharger on our KAD32's powered Targa 30 was on constantly making a hell of a racket. And even in the first season the engine room would be full of belt dust.