i have twin Volvo 74P EDC engines in my 2002 Carver 450 Voyager. There is normally a 1 second delay when the throttles are engaged, however the starbord control now has a 3 second delay when put in forward gear. reverse gear has the normal 1 second delay. anyone experience this problem and what is the possible cause? Thanks for yor help
Hi, There is a potentiometer (No.12) in the control of the EDC. Does the problem happen on the bridge and flybridge? Then it may be the MS unit. You will have to trace the problem by process of elimination. Volvo Penta Exploded view / schematic Control for Top Mounting, EDC 2: B TAMD74C-A, TAMD74C-B, TAMD74L-A, TAMD74L-B, TAMD74P-A, TAMD74P-B, TAMD75P-A - MarinePartsEurope.com
On most of the units you can go in an adjust the time delay. Is it possible that the one engine delay had a fault interuption and needs to be reset.
A very good point, if the OP could let us know if it occurs on both Port & Stb controls or just one engine.
edc controls the problem occurs on the starboard engine only at both the upper and lower helms. another problem that has come up is with the port engine. it stalls after 15-30 minutes. rpm fluctuates and then the engine stalls. just had the fuel polished and the fuel injector pump rebuilt and the injectors cleaned.
There is a valve on the Turbo that can get clogged and not work correctly that makes the motor run like an asthmatic hog. Check part No. 29. Volvo Penta Exploded view / schematic Turbocharger, Components: 3837691 TAMD74A, TAMD74A-A, TAMD74A-B, TAMD74C-A, TAMD74C-B, TAMD74L-A, TAMD74L-B, TAMD74P-A, TAMD74P-B, TAMD75P-A - MarinePartsEurope.com
That is a waste gate that is normally closed at low power. Like every other turbocharged engine the Volvo starts as a naturally aspirated engine and unless the "stalling" issue occurs under power it has nothing to do with the condition of the wastegate. If the wastegate were stuck open the engine would probably start and idle normally but smoke black on acceleration then run just fine at high power. If it were stuck closed, unless there is a manifold pressure compensation system on the governor, you might overboost the engine at high loads.
volvo 74Pedc the engine stalls under load 2200 rpm and at low speed 600-1200 rpm and just about any speed in between. air cleaners are clean,fuel filters new,checked the connections to the fuel injector pump and they seem ok. as well. Bull Durham
It sounds like there might be an intermittent fault (ground or open) on an engine sensor connector somewhere. If you (or your favorite tech) can download the data you should be able to pinpoint the offending item.
Having gone through the physical parts of the Gearshift, Fuel and Breathing; the last and most frusratrating parts to work on are the Electronics. Have a look at my first post were it goes the the picture of the gearshift, click out to the shift electronics sub-section and you will see the MS unit. It is often mounted between the flybridge and lower helm and hard to find. The connections sometimes get corrosion on them, make sure they are cleaned and all good. Not cheap to replace, unfortunatley. As Marmot said, a good Tech should be able to trace an electrical fault through the EDC codes. There, done for you Volvo Penta Exploded view / schematic MS Unit TAMD74C-A, TAMD74C-B, TAMD74L-A, TAMD74L-B, TAMD74P-A, TAMD74P-B, TAMD75P-A - MarinePartsEurope.com
edc controls fishtigua, thanks very much for all your asistance. i'll let you know the outcome. the tough part is finding that competent mechanic !!!
It sounds like it's an electrical issue having to do with the ignition switches or power going to those or the controls, I would check your wiring going to the ignition switches and from their to the ECU's and then to the engine.
J, You may be right. The electronic units on the Flybridge often get fried in sunlight and crumble. Check the button pack. Volvo Penta Exploded view / schematic Monitoring Panel for Single and Two Or More Stations: B TAMD74C-A, TAMD74C-B, TAMD74L-A, TAMD74L-B, TAMD74P-A, TAMD74P-B, TAMD75P-A - MarinePartsEurope.com
tamd 74 edc control turns out the problem with the controller was related to a clogged filter on the solonoid which is connected to the transmission.as you know there are two solonoids on the top of the transmission for reverse and forward. if you remove the solonoids the shaft they attach to can then be removed. there is a metal screen near the end of each shaft that collects debris such as metal shavings etc. it appears this was enough to interfere with the operation of the solonoid causing the delay in shifting. now if i can just resolve the stalling issue........