Volvo KAD 300 losing revs

Eastbourne.

We've had the issue since we bought the boat. Sometimes it loses the neutral position on the starboard throttle. I can do a re calibrate and it comes back.

It's happened twice recently under load, which made me wonder if the EDC wasn't seeing a correct voltage. Has also happened when we have been at moored but using the boat for a few days. (Again, power loss?)
 
Eastbourne.

We've had the issue since we bought the boat. Sometimes it loses the neutral position on the starboard throttle. I can do a re calibrate and it comes back.

It's happened twice recently under load, which made me wonder if the EDC wasn't seeing a correct voltage. Has also happened when we have been at moored but using the boat for a few days. (Again, power loss?)

Sounds like a fault potentiometer, easy fix
 
Hi Paul,

I had the new Pot fitted. It hasn't resolved the issue. When i turned the EDC on I was also unable to go into the calibration mode.

Nest morning for some reason I tried again and the throttles were in neutral as soon as I turned the keys.

Any thoughts?

Cheers Simond
 
VOLVOPAUL Please let me know what you did to resolve the loss of rpm (how to calibrate evc - and what else you advised)
 
Hi,

I have a similar issue to yours. are you able to tell me what the SPM unit is, looks like, and where it is fitted in the system.

I'd like to see if I have it already fitted or if it is something i can retro add to my 2004 KAD300's

Simond
@volvopaul Hi Paul, is the SPM ever required on a kad44edc engine? I believe a neighbour had it fitted on his T34.
 
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Just to ask what is a SPM and what does ' I fired a unit at it' actually mean ?
I have the moody starboard engine running uptown 3k revs and no more with no turbo boost - only got to 3k after being stuck at 1800 until we cleaned the relay - now being pointed in the direction of switch ECU to see if faulty boost valve - wondering if VPaul has any input to this solution and the SPM bit above....thanks
Nick
 
The SPM Signal Processing Module unit was introduced by Volvo to combat an issue with engines falling into gear without touching the controls , basically as time has progressed wiring deteriorated causing spikes, voltage drops and rises , in turn altering resistance readings .

The SPM unit is connected between the throttle potentiometers and the 3 pin plug to the HCU , it’s there to smooth out the voltage and modify the signal to the shift actuators via the engine ECU .

At first we were only fitting to twin helm station boats but only at the lower helm , over the years I’ve seen them fitted to both helms to combat stray issues with drive dropping out , engines going into limp mode etc , in fact there are many on going issues with this early generation edc .

some owners will never have issues , yet one contacted me only today with his problems going into reverse on its own , single helm TAMD 75P a 2002 boat, I’ve known this boat nearly 10;years now and this is the first time he has had issues.
 
Just to ask what is a SPM and what does ' I fired a unit at it' actually mean ?
I have the moody starboard engine running uptown 3k revs and no more with no turbo boost - only got to 3k after being stuck at 1800 until we cleaned the relay - now being pointed in the direction of switch ECU to see if faulty boost valve - wondering if VPaul has any input to this solution and the SPM bit above....thanks
Nick
Nothing to do with SPM
 
The SPM Signal Processing Module unit was introduced by Volvo to combat an issue with engines falling into gear without touching the controls , basically as time has progressed wiring deteriorated causing spikes, voltage drops and rises , in turn altering resistance readings .

The SPM unit is connected between the throttle potentiometers and the 3 pin plug to the HCU , it’s there to smooth out the voltage and modify the signal to the shift actuators via the engine ECU .

At first we were only fitting to twin helm station boats but only at the lower helm , over the years I’ve seen them fitted to both helms to combat stray issues with drive dropping out , engines going into limp mode etc , in fact there are many on going issues with this early generation edc .

some owners will never have issues , yet one contacted me only today with his problems going into reverse on its own , single helm TAMD 75P a 2002 boat, I’ve known this boat nearly 10;years now and this is the first time he has had issues.
Glad you have said this ,
I have commented on loom insulation issues many times before and felt its fallen on deaf ears .
About 6 /7 years ago my Fr equivalent of you told me words to same effect .. As time goes by the loom resistance changes due to ageing .They at the time ( local on the job tech s ) were not sure exactly the aetiology ........the suggestion at the time was a breakdown in the insulation of the actual wires .Leading to changes in resistance ..Results in all sorts of spurious symptoms.Which take time to pin down .

A tell tale then for me was rise in temp gauge .Infra red thermo said the correct temps were ok .New gauge + sender zero effect ...so its the loom .Even stopped umbilicals across to confirm the diagnosis.
He had seen this + other issues many times before .
For me i tried to hang on to the VP thing , because like everyone else the numbers out there speak for themselves so it follows they must be ok .Seems a natural conclusion to arrive at .
Any how as time went by I lost total confidence in the product.
Did a 9 year stint with KAD 300 s .....have a few hobby cars and when I cross referenced the basic engineering trying to take into account the marine thing I just bailed out - woke up one morning , smelt the coffee .
eg the rocker box / valve adjustment.....no gasket and they run the fuel pipes ( which corrode / paint flakes off btw ) over the top .
I mean squeeze y black sealant ....pleeeeeese .Thats alien to basic engineering, I am familiar with as a hobbyist working on engines Why not a machined grove + a double alloy and rubber gasket that fits in said groove .Fitted In such a away you can easily remove to adjust the tappets??
They are not cheap either it’s not as if you can play the Chinese knock off card from e- bay ......whereby you accept a bit of cost cutting .
The loom deterioration was the nail in the coffin for me.
At the time I was not offered a after market retro fix .Just a Gallic shrug of the shoulders.

Don’t know of any other ICE ( marine or land ) that needs a device retro fitted some time later to compensate for changes of resistance to the loom as it ages .

With a car you just pull up on the side of the road open the bonnet and stand on the hard shoulder with your phone glued to your ear . You can’t do that with a boat , well i was not prepared to take the risk having been made aware by my Fr equivalent of Volvo Paul .
 
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