Coolantpump troubles KAD32

novanta

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We have here a Targa 30 with twin KAD32's. They were for years complete trouble free, we only did every year normal engine and drive service. Two years ago, the starboard engine suddenly overheated. We had a look at it, first the strainer/impeller and the thermostats but it appeared to be the coolantpump. We changed it for a new one and we saw that the shaft of the old pump was broken. Strange but okay, **** happens. After a few days the owner had the same problem again! We could not believe that is was the same problem but in the end there was nothing else left... So we got the pump of the motor and again, the shaft was broken! To make a long story short: this happend 4 times! But the last time we put the new pump on the port engine and changed that old pump to the starboard engine. After 10 hours he called us: Bingo, now the port engine has the problem! We always tension the belts with the correct moment so there is no change of putting the belts to tight. I asked our Volvo dealer (we are a yachtservice special for fast motoryachts but no Volvo dealer) and he is very helpfull but Volvo have not got a answer yet. Problem is that my client has a vacation plannend in two weeks and this problem is now for almost two years! The only thing I can think of is to get a used pump from a old engine to get the boat running again.

Are there more problems with coolantpumps with the 31/32/41/42/43/44/300?

Thanks, Ronald.
 
We have here a Targa 30 with twin KAD32's. They were for years complete trouble free, we only did every year normal engine and drive service. Two years ago, the starboard engine suddenly overheated. We had a look at it, first the strainer/impeller and the thermostats but it appeared to be the coolantpump. We changed it for a new one and we saw that the shaft of the old pump was broken. Strange but okay, **** happens. After a few days the owner had the same problem again! We could not believe that is was the same problem but in the end there was nothing else left... So we got the pump of the motor and again, the shaft was broken! To make a long story short: this happend 4 times! But the last time we put the new pump on the port engine and changed that old pump to the starboard engine. After 10 hours he called us: Bingo, now the port engine has the problem! We always tension the belts with the correct moment so there is no change of putting the belts to tight. I asked our Volvo dealer (we are a yachtservice special for fast motoryachts but no Volvo dealer) and he is very helpfull but Volvo have not got a answer yet. Problem is that my client has a vacation plannend in two weeks and this problem is now for almost two years! The only thing I can think of is to get a used pump from a old engine to get the boat running again.

Are there more problems with coolantpumps with the 31/32/41/42/43/44/300?

Thanks, Ronald.

These pumps don't break like this but as the pump is driven from the crank then it drives the supercharger and alternator I'd say there must be issues that must be rotational in relation to the other driven items. You have been unlucky but the engineer should have pointed this out to you that after say the second pump there must be something else wrong. I'd be checking bearing wear, and crankshaft alignment for a start, something must be out of line for this to keep happening .

Tell me what tension are you setting and is it the later type with 14mm bolt head on the tensioner with 15mm nut to lock it off or the earlier type that used two Allen Keys to set up.
 
Hi Paul,

I thought that KAD32 is always the new style tensioner with the 14mm and 15mm nut. I have to check the tension we use tomorrow but I know it's correct and we are using it for years! The second pump is fitted bij our Volvodealer because we were in France at that time so he fitted the pump for us. How do you explain that the complete new pump, now fitted on the port engine, is broken again? Do we have two engine's with the same problem? It's hard to believe. We have thought of perhaps someone has dropped a little nut or washer into the coolant tank or maybe the is a big piece of rust in the cooling system, blocking the pump vanes. Hard to believe because we could not see any damage to the broken pumps but thats wy we fitted the last pump on the other engine.
 
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Have you checked the oil level in the Superchargers recently?

I had only one pump go a bit wobbly on my KAD32's - VolvoPaul changed it before it failed completely, and it's been fine ever since.
 
I have replaced one of these pumps on a Kad32 a few years ago as the shaft had sheared. The pump has been ok since. Is the new pump coming with a flange for the pulley or are you having to remove the flange from the old one and fit to the new one.
 
Bingo! There is a new service bulletin from Volvo about these pumps! New pumps are now available with a new shaft and bearings..
 
Bingo! There is a new service bulletin from Volvo about these pumps! New pumps are now available with a new shaft and bearings..

Strange how things happen, one of my kad 43's just overheated mid holiday :( A quick assessment indicates the coolant pump which I changed a few years ago so now I am suspecting the same issue you had. Do you or anyone else have a reference to the service bulletin so that I can make sure I get the right pump?
Thanks.
 
Strange how things happen, one of my kad 43's just overheated mid holiday :( A quick assessment indicates the coolant pump which I changed a few years ago so now I am suspecting the same issue you had. Do you or anyone else have a reference to the service bulletin so that I can make sure I get the right pump?
Thanks.
I have just gotten the pump off and indeed the shaft is broken and no signs of the bearings being damaged. Would really appreciate any insights to the service bulletin referenced (or any other insights)
primarily to get the right pump but also to try and reclaim the cost of the newly changed and now broken pump.
 
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