Volvo penta kad44 only revs to 1200rpm

[Perry8007]

Hi Perry, i ran a pair of 44s for 3 years and looking at that video, the supercharger clutch cutting in and out combined with odd noise is not something i remember. They normally start on the button and tickover is rock solid, looks like you have fuel ok though.

Yep got heaps of fuel coming up just can’t get it to rev

 

[A_8]

That supercharger does not sound right at all and I think it took way to long to start. Did I notice correct that when you opened one of the fuel lines it did not change the ruff idle so at least one of the cylinders are not getting their fuel right.
I just looked at the video and have not read what have been written already but have you checked if the SC is actually pressing air while engaged ?
I think you have several issues going on at the same time including maybe an air leak in the fuel system.

 

[rickwales]

Check your fuel rail pressure sensor and limiter, especially if you have proved the injectors to be ok

 

[rickwales]

My mistake I was confusing it with a later common rail engine, it’s still worth checking fuel pressure though because it’s giving you that kind of symptom

 

[petem]

I'd forget turbos, superchargers, etc.

That engine isn't even starting as it should (I have a KAD44 and it starts in a fraction of that time, even if left for a couple of months). Fix that problem and the other issues might go away.

Go back to the fuel supply suggestions in post #3....

Could also be fuel blockage .
Have you connected fuel hoses correct , fuel from filter to inlet side of lift pump .
There is also a fuel banjo connector you can fit incorrectly that will still allow fuel in but at a restricted flow , this should be connected to outlet hose top of injection pump . That will keep you busy .

Are you sure the fuel lines don't have a blockage, air leak or have collapsed in some way?

Pete

 

[rickwales]

I'd forget turbos, superchargers, etc.

That engine isn't even starting as it should (I have a KAD44 and it starts in a fraction of that time, even if left for a couple of months). Fix that problem and the other issues might go away.

Go back to the fuel supply suggestions in post #3....

Could also be fuel blockage .
Have you connected fuel hoses correct , fuel from filter to inlet side of lift pump .
There is also a fuel banjo connector you can fit incorrectly that will still allow fuel in but at a restricted flow , this should be connected to outlet hose top of injection pump . That will keep you busy .

Are you sure the fuel lines don't have a blockage, air leak or have collapsed in some way?

Pete

There is still a fuel pressure valve on this engine, I would assume that the owner has already investigated the basics, fuel lines filters, air in system- if not need to check the basics first!

 

[Portofino]

It’s been a while now over 5 years since I bailed out of the whole VP KAD power plant thing .
A tech , a good tech who I had built up a good relationship over the years of ownership while investigating a problem said over the years the wiring harness's decay . In the sense the resistance of certain parts , more accurately the wires that lead to them increase and this throw s sensors out and you end up with “ implausible signals “ flying around the ECU s .

What you have to do if it’s a twin is swap components to eliminate.So even the new crank sensor .....ok it works but it’s signal isn’t “ plausible “ by the time it’s been carried to the ECU by the duff harness .
This duff harness might explain where you are ?

 

[rickwales]

It’s been a while now over 5 years since I bailed out of the whole VP KAD power plant thing .
A tech , a good tech who I had built up a good relationship over the years of ownership while investigating a problem said over the years the wiring harness's decay . In the sense the resistance of certain parts , more accurately the wires that lead to them increase and this throw s sensors out and you end up with “ implausible signals “ flying around the ECU s .

What you have to do if it’s a twin is swap components to eliminate.So even the new crank sensor .....ok it works but it’s signal isn’t “ plausible “ by the time it’s been carried to the ECU by the duff harness .
This duff harness might explain where you are ?

Wiring loom problems are extremely common on trucks in the 2 to 7year old bracket and a break in the loom often causes limp mode type problems, marine looms are a bit simpler but same principles can apply

 

[Portofino]

Wiring loom problems are extremely common on trucks in the 2 to 7year old bracket and a break in the loom often causes limp mode type problems, marine looms are a bit simpler but same principles can apply

There’s a distinction between “ open circuit “ or “ short to GnD “ which are from broken wires and .....

” implausible signal “ which is what I,am advocating Theres no break in the loom .

 

[rickwales]

Agreed but one of the common issues on truck engines is the loom deteriorating and causing random faults, testing with a meter doesn’t always pick it up, my best tech will often put a dummy load through each cable pinning it back to ECU, again I’m talking about direct issues within truck wiring and can networks

 

[Perry8007]

It’s been a while now over 5 years since I bailed out of the whole VP KAD power plant thing .
A tech , a good tech who I had built up a good relationship over the years of ownership while investigating a problem said over the years the wiring harness's decay . In the sense the resistance of certain parts , more accurately the wires that lead to them increase and this throw s sensors out and you end up with “ implausible signals “ flying around the ECU s .

What you have to do if it’s a twin is swap components to eliminate.So even the new crank sensor .....ok it works but it’s signal isn’t “ plausible “ by the time it’s been carried to the ECU by the duff harness .
This duff harness might explain where you are ?

 

[Perry8007]

Hi it’s not twin set up
I have also changed the engine wiring harnesses still the same
Was running a lot better than this a week ago and all I’ve done is replace the starter motor
Don’t no what’s going on now this is a new problem

 

[Perry8007]

Still have no fault codes coming up at all

 

[volvopaul]

Does your engine have a separate EDC power supply , the early 44s did .
They did away with it on the 300 and fitted a DC DC convertor to keep the edc voltage stable on start up.
Your issue sounds like a wiring problem .
In the area forward of the starter you will see a plastic block , this is the pos and neg edc feed , this must be direct to the start battery in order to maintain as much voltage as possible .
I have seen builders loop the feeds to the starter , yes I know builders don’t understand , they just make the installation as easy as possible .
I have before had to re wire some boats ( builder to remain anonymous) American .
Looks at your u tube vid on starting it sounds like you have good start voltage , if all is good 44s start fairly well.
As I’ve said before if the crank sensor doesn’t give its inductive pick up signal it won’t allow the alpha solenoid to open to allow fuel to the cam head inside the injection pump.
You WONT get a fault code , I know this from experience on a Targa 34 some years back.
The loom was green , the bellows had split allowing water into the flywheel housing which in turn rusted the flywheel , the flywheel must be clean and swarf fee to make the signal .
Take out the sensor , clean the flywheel and the sensor , it will only give a fault code when you unplug it.
Off you go.

 

[rickwales]

So it was running ok before you changed starter?

 

[volvopaul]

So it was running ok before you changed starter?

Read the post from the start , no it wasn’t .

 

[volvopaul]

If you can’t get the diagnostic key to read for example the boost temp, water temp edc etc then you need to read the resistance figures on each sensor , you could for example have a ghost high boost temp or pressure figure , or a high water temp figure , again a ghost figure .
I once had a 44 that wouldn’t start , there was over 30 stored repeat fault codes which you can only clear with the tool, once cleared history it started first go .
Again this system was a real guinea pig for Volvo more concentrated on making an engine work from fly by wire , the fault finding was a back seat design .
Who ever worked it should keep well away from the aviation industry.

 

[volvopaul]

I’ve just read your first post, have you had the cover off the edc computer ?
The boost sensor when failed or not connected does not give a fault code , make sure the connector is on the sensor inside the computer .

 

[Perry8007]

I’ve just read your first post, have you had the cover off the edc computer ?
The boost sensor when failed or not connected does not give a fault code , make sure the connector is on the sensor inside the computer .

Hi yes have just had the cover off and checked it and it’s plugged in and dry

Does your engine have a separate EDC power supply , the early 44s did .
They did away with it on the 300 and fitted a DC DC convertor to keep the edc voltage stable on start up.
Your issue sounds like a wiring problem .
In the area forward of the starter you will see a plastic block , this is the pos and neg edc feed , this must be direct to the start battery in order to maintain as much voltage as possible .
I have seen builders loop the feeds to the starter , yes I know builders don’t understand , they just make the installation as easy as possible .
I have before had to re wire some boats ( builder to remain anonymous) American .
Looks at your u tube vid on starting it sounds like you have good start voltage , if all is good 44s start fairly well.
As I’ve said before if the crank sensor doesn’t give its inductive pick up signal it won’t allow the alpha solenoid to open to allow fuel to the cam head inside the injection pump.
You WONT get a fault code , I know this from experience on a Targa 34 some years back.
The loom was green , the bellows had split allowing water into the flywheel housing which in turn rusted the flywheel , the flywheel must be clean and swarf fee to make the signal .
Take out the sensor , clean the flywheel and the sensor , it will only give a fault code when you unplug it.
Off you go.

hi flywheel is clean and we have put a new flywheel sensor in
It has two black box’s .one negative going straight to the battery and one positive going through a battery switch all have been cleaned
Will recheck starter wires as it is not starting very well now and won’t rev at all
It’s as you said it’s not getting fuel

 

[Perry8007]

That supercharger does not sound right at all and I think it took way to long to start. Did I notice correct that when you opened one of the fuel lines it did not change the ruff idle so at least one of the cylinders are not getting their fuel right.
I just looked at the video and have not read what have been written already but have you checked if the SC is actually pressing air while engaged ?
I think you have several issues going on at the same time including maybe an air leak in the fuel system.

Hi yep supercharger is making heaps of air can’t hold your hand over the hole when you take a manafold plug out