Volvo penta kad44 only revs to 1200rpm

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Remove the sea water pump and run it up for a short time . If it improves the situation let me know and I will explain the reason it’s improved.

On a KAD32 I had something similar where a rebuilt seawater pump had the shaft bearings not quite in the right place. This was causing excessive pressure on the fuel pump drive - rough running, and not many revs above idle.
 

volvopaul

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On a KAD32 I had something similar where a rebuilt seawater pump had the shaft bearings not quite in the right place. This was causing excessive pressure on the fuel pump drive - rough running, and not many revs above idle.
Correct , it applies pressure on the cam head not allowing fuel pressure to be maintained .
 

Perry8007

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Hi .
I think we have found it got sent a mercruiser injector pump to try and what a difference it starts and runs up to 1500 to 2500ish unreal
Have put videos on you tube Blackmail kad44
Will be calling dsl the pump shop on Monday see what they have to say.
 
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A_8

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Hi .
I think we have found it got sent a mercruiser injector pump to try and what a difference it starts and runs up to 1500 to 2500ish unreal
Have put videos on you tube Blackmail kad44
Will be calling dsl the pump shop on Monday see what they have to say.
That sounds promising but perhaps find another pump shop whatever they say.
 

Perry8007

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Hi there
We are getting there now
We have just tried the second hand ecu with the merc pump and what a difference
Now she starts straight away and now revs to 3000rpm after that starts to surge and we have smoke but there is no load on anything
But it sounds good
New video up YouTube Blackmail kad44 316 minutes
Cheers hopefully fishing soon
 

petem

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Perry, when I looked earlier today, I could only see videos from 3 days ago. Is there a new one? Can you post a link to it.

Also, your ECU, is it definitely the correct part number? Have you checked what it says on the side against the VP parts list?

Regarding the Mercruiser injection pump, I'm guessing that this is might be calibrated differently to your original VP one. Also, is the company that you're using for the pump actually a Bosch service centre. Are they definitely calibrating it as per the VP settings (if they're really incompetent then there are centres in the UK and USA that I'm sure would be better and cheaper) than NZ.
 

Perry8007

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Perry, when I looked earlier today, I could only see videos from 3 days ago. Is there a new one? Can you post a link to it.

Also, your ECU, is it definitely the correct part number? Have you checked what it says on the side against the VP parts list?

Regarding the Mercruiser injection pump, I'm guessing that this is might be calibrated differently to your original VP one. Also, is the company that you're using for the pump actually a Bosch service centre. Are they definitely calibrating it as per the VP settings (if they're really incompetent then there are centres in the UK and USA that I'm sure would be better and cheaper) than NZ.
[/QUOTENew video on here now
 

Perry8007

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Hi
The ecu is our one and has always worked before
I’ve now got to put the new pump back on and get some pics and videos of how it runs
Then have a go at the pump people
 

Perry8007

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Hi there
Got the injector pump back had been to another diesel shop
Put it back in in had it timed
Dose the same thing only revs to 1200 rpm
Took a long time to bleed up and is not starting very well
Doing the same thing as before
Have talked to the shop that worked on it Said they tested through the whole rev range tested great
They checked it twice
Talked for half an hour with him
Said it can not be the pump
 

QBhoy

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Hi .
I think we have found it got sent a mercruiser injector pump to try and what a difference it starts and runs up to 1500 to 2500ish unreal
Have put videos on you tube Blackmail kad44
Will be calling dsl the pump shop on Monday see what they have to say.
Did you really rig up an injection pump from a mercruiser, onto a VP Kad engine ?? Any pics ?
 

jrudge

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So I know little about injection pumps - but I assume you had to do some significant modification to make a mercruiser one work ?

The pump I assume talks to the ECU and also has input from various sensors ( or they may go through the ECU).

Given pump timings etc will be different I am surprised it ran at all but I would suggest you give exact details of how you got the Mercruiser one working and someone in the know can try and spot the difference as to where this is going wrong.

Diesels in principal are quite simple things. Fuel - compress - bang. You seem to have proved that the basic operation works with another pump - but I assume you did not take the boat out etc which would require a huge fuel demand compared to idle ( or fast idle) in the marina.

You probably need to accept that the pump is OK given 2 people have said it checks out. The only thing there is how do they test? Does it get tested under a real life fuel flow load? If not could there be something that collapses once the flow goes up?
 

volvopaul

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So I know little about injection pumps - but I assume you had to do some significant modification to make a mercruiser one work ?

The pump I assume talks to the ECU and also has input from various sensors ( or they may go through the ECU).

Given pump timings etc will be different I am surprised it ran at all but I would suggest you give exact details of how you got the Mercruiser one working and someone in the know can try and spot the difference as to where this is going wrong.

Diesels in principal are quite simple things. Fuel - compress - bang. You seem to have proved that the basic operation works with another pump - but I assume you did not take the boat out etc which would require a huge fuel demand compared to idle ( or fast idle) in the marina.

You probably need to accept that the pump is OK given 2 people have said it checks out. The only thing there is how do they test? Does it get tested under a real life fuel flow load? If not could there be something that collapses once the flow goes up?
Pump gets tested by a motor that’s variable speed so in effect the pump is driven at whatever speed the motor is run at .
It’s a bit like the chicken and the egg situation in that no one can work out what the issue is .
The pump is a Bosch VE electronic, the pump bodies are identical much of the internals are the same ,I’ve had this before with a kad43 , pump went to 3 different shops , in the end we fitted a brand new pump it was the only cure possible .

I’d say it’s a delivery problem in the cam head as low rpm can only be the lack of fuel nothing more , timing not under load has little effect .

I’d say there is still an issue with your pump which the shop can not replicate On the dyno because the dyno is running the pump , not the engine.

There is obviously no issue with the merc pump, I had pretty mush the same issue , fitted a pump from another engine it was sorted .
 
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