Volvo KAD44 erratic tickover

ribber

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I've just bought a Maxum 2700 with a KAD44 with 135 hours.

When we tried to launch yesterday, engine started fine, but then started to "hunt" at tickover, going up to about 1000 revs the back down - up, down, up down then stall. Started again fine, then would do it again and again. If you throttled up to 1000 to 1200 revs, it would seem fine and hold OK, throttle off and it would do it again.

A friend who has had this engine before says it is probably air in the fuel/filter and bleeding should cure - cost next to nothing

My Volvo dealer/engineer says it is probably the injector pump and/or injectors that may have corroded as the boat has been sat for sale for 6 months - cost £2500 !!!

Anyone heard of this before?
 

ribber

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Hi,

Yeah, that's what he said, if left standing for a while condensation in the fuel causes the pump to corrode. Sometimes it can clear itself but it's doubtful. Looks like an exchange unit!
 

DAKA

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the flexible fuel line cracks after 5 years and allowes air in that can cuase these symtons.

Your cheapest option is to remove the flexible fuel line and inspect it for cracks.

You cannot see the hair line cracks in a dark crampted bilge.

If your boat surges as well I would say 70% chance of your flexible pipes.

if they are 5+ years old time to replace anyway before they let you down.
 

spannerman

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Same as Volvopaul, these semo electronic pumps can't tolerate water like the older purely mechanical ones, the electronics in the pump that sense fuel temp and adjust the governor give up at the first sign of water.
The Mercruiser engines with same type of pump specify in the owners manual that the water seperator should be drained daily, but no one ever does, but £5000 (norwegian price) for an exchange pump usually cures people!
Sounds like this could be the problem unfortunately.
 
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