Volvo EDC unit

[Brad3311]

This has happened twice this weekend. Cruising slow at about 1000 rpm' sand the port engine drops to below 700 and while the shift lever is still in forward the port engine goes into reverse. The only way I could get the engine out of reverse was to shut the engines off. Someone said the fuel filters may need to be changed but I never had an engine flip into reverse without me shifting into it. Can the EDC units on the Volvo go haywire? Just wondering if you had ever heard of that situation?

 

[vas]

better post that in the motorboat section of the forum, many twin engined Volvo owners there, EDC mentioned often (and not for good!) a search of EDC posts will probably help you with some pointers...

 

[RichardS]

This has happened twice this weekend. Cruising slow at about 1000 rpm' sand the port engine drops to below 700 and while the shift lever is still in forward the port engine goes into reverse. The only way I could get the engine out of reverse was to shut the engines off. Someone said the fuel filters may need to be changed but I never had an engine flip into reverse without me shifting into it. Can the EDC units on the Volvo go haywire? Just wondering if you had ever heard of that situation?

Dirty fuel filter flipping the engine into reverse gear? I would be interested to hear if there is any justification at all behind this idea as it seems totally impossible.

Richard

 

[Moodysailor]

This has happened twice this weekend. Cruising slow at about 1000 rpm' sand the port engine drops to below 700 and while the shift lever is still in forward the port engine goes into reverse. The only way I could get the engine out of reverse was to shut the engines off. Someone said the fuel filters may need to be changed but I never had an engine flip into reverse without me shifting into it. Can the EDC units on the Volvo go haywire? Just wondering if you had ever heard of that situation?

I'm assuming these are KAD series engines?

I've had a couple of throttle potentiometers (in the levers) go bad over the years. The issue can be interrogated with an EDC key or diag tool, but it needs to be plugged in when it happens.

 

[Brad3311]

I'm assuming these are KAD series engines?

I've had a couple of throttle potentiometers (in the levers) go bad over the years. The issue can be interrogated with an EDC key or diag tool, but it needs to be plugged in when it happens.

Are potentiometers easy to change out?

 

[Moodysailor]

Are potentiometers easy to change out?

Yes, a simple swap. The challenge is usually getting the control head off (dependent on access underneath). Once done, it will need calibrating, which is easy enough.

 

[Brad3311]

Yes, a simple swap. The challenge is usually getting the control head off (dependent on access underneath). Once done, it will need calibrating, which is easy enough.

Any idea where to buy them? Also I suppose one you have it off probably do both

 

[Moodysailor]

Any idea where to buy them? Also I suppose one you have it off probably do both

When I was doing these I worked at a dealer. What I do know is that the potentiometer is quite common, so could probably source one online.

I'm not guaranteeing this is the issue though - could just as easily be a voltage drop in the cables. If you haven't already, try re-calibrating, with the battery charger off.

The throttle potentiometer is just a variable resistor. What we found is that the engine could see a different voltage than that "seen" during calibration, the values are quite small, so a 0.1-0.3v swing could be the difference between being in neutral or in gear (just an example). Calibrating when the batt charger is off allows the battery voltage to normalise so it doesn't create a falsely high reading. These faults are a a little tricky to diagnose, especially without a diag. tool - start at the basics first.