Troubleshooting TAMD75 EDC on possible purchase

SeaNile

Well-Known Member
Aug 16, 2010
1,514
Chadds Ford, PA
Boat Info
2003 50 Sundancer
Engines
Cummins QSM11
This is a good one, but hang in there and let me explain. Looking at a 2003 Regal 4260 with twin TAMD 75, 550hrs. Owner has discounted the boat due to the unknown issue which happened in October and has not had it looked at yet. Boat is on the hard and winterized. Here is how he describes it....


A few weeks ago I took the boat out and the starboard EDC (Volvo’s electronic transmission control) started to act up. Boat ran up to almost on plane, then went into neutral. Turned around and went back in. Starboard forward was disengaged. I only had reverse. This may be anything from a loose connection to possible needing a trans overhaul. I am almost certain it’s something electronic. I’ve dropped the prices considerably to move the boat on.

Took the boat out many times this summer. She ran great. Summer prior (2018) I had a very high powered stereo hooked up to my 2 starter batteries in my 2003 Regal 4260 Express. My port side would go dead and I'd only have starboard to dock the boat. No forward, no reverse. I discovered one of the 3 breakers in the control box mounted on the side of the engine would pop. I'd push it back in and the controls would start working again. Ultimately, I replaced the breaker and port side has run flawlessly. Fast forward to summer of 2019. Startboard side starts acting up. Nothing at all in forward. Reverse was perfect. I suspect stereo hooked to engine batteries was interfering with EDC's. Pulled stereo off batteries, take her for a run, she runs perfectly. Summer of 2020; all is great until October when I take her for a run. She would pull hard until almost on plane, then just drop into neutral. Engine would rev, but no forward thrust. Reverse is perfect. Oil sample shows 358ppm for copper, 98ppm for aluminum, which Wix says is abnormal. Not severe which is their worst grade. I'm not sure if when the engine was pulling onto plane, then went into neutral and just revved, did it slip the clutch by possibly the solenoid being partially open and increased the level of copper? I'm trying to figure out if I have an electrical problem and or if the trans is in need of a rebuild. I swapped solenoid from forward to reverse on trans and nothing changed. Figured if seloniod was bad, I'h have no reverse with the swap. Thanks for anyones help!

Thoughts on the issues? Engines run so I doubt its the EDC in its entirety. Not sure if I should pursue this boat or to run away. Price reflects the unknown issue which could be simple or could be expensive and a lengthy repair?

Thanks as always.
 
How much has it been "discounted" enough to cover a complete transmission rebuild?
How much do you like the boat and are others out there at a fair price?
It's not your boat yet what is the current owner willing to allow?
And now days the electronics I have no idea how expensive some of that can get, depends on parts and the labor to diagnose.

Given those things only you can decide, if it were my boat this is what I would be checking...

So I only have neutral and reverse,
I swap the solenoids and it makes no difference, so I still have N & R

I would swap the wiring on the two solenoids, not the solenoids in the valve block.
then carefully while secured to the dock,
now "reverse" should put the trans in forward and "forward" should put the trans in reverse.
what happens?
If still no forward gear at all, and still has reverse gear (but controls are backwards) - transmission problem, electrical ok
If now have forward gear, but no reverse gear (with controls backwards) - Transmission is ok, electrical problem

Now this needs to be done in the water, might be able to do on the hard with a water supply, but not for more than a few seconds in gear. You'll kill the cutlass bearings and shaft seals running dry.
 
Good info. Boat is winterized and possibly blocked in due to storage. Owner is completely OK with putting boat in the water for survey, etc.
Boat is discounted a lot based on NADA value and other similar boats listed for sale.
 
I just put up something in your other thread. Bottom line, this is an electronically controlled propulsion package and has some maintenance issues associated with it and some basic electrical components. See my other post.

My bet is it's quite fixable. Cost is another issues. Volvo in my experience (I owned an Volvo I/O years ago) makes great products, but parts are hard if not impossible to get and expensive when available, especially as things age.

I guess it depends on how handy you are and how much time money you want to invest instead of turnkey boating.
 
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My friend had a 2006 version of that boat. I worked on it regularly including this issue. In the end a Volvo mechanic had to come down and look at it. In this case it turned out to be the shift control pcb on the engine and the a chip in the helm controls (the electronic shifting) as well. That was tied into the engine start panel by the steering.

Not sure if those years are exactly the same or not as I don't Regal/Volvo that well. But if they are the port engine has the exhaust come up and over the engine to exit the boat. There is a small section 1-2' of cast exhaust pipe before the shower head. That has a vertical curve to it and sea water gets down by the turbo and rust's out the flange causing a turbo replacement. We replaced the turbo 3 times in 8 years. Replacing that exhaust riser twice, a very hard part to find, took over a month to get the last time it was replaced.

The other thing I would be leery of is the engines going to neutral under a load. That and you don't really know how many times that happened, but in that condition the engines had to red line for a few seconds and that can cause issues down the line for both the trans and engine.

My friend had a lot of issues with that boat and couldn't wait to sell it. That said it was a very nice boat.
 
I am facing similar issues. Have you ever figured it out?
 

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