MDC Delete and Analog Gauge Replacement How To

[master sm]

Ok I am about to order the Faria gauges. Not going with the six pack since I want the GPS Speedo and the Tach with hour meter. I have a 2001 Maristar 230 and I believe I have the MDC and can follow the original write up almost exactly. My only question is the fuel sending unit. I have the Moeller 395-075 Maristar 2001. I am planning on ordering the Wema SSS but have seen where people have ordered 10", 9", & 9.5". Does anyone know which is the best fit so I don't have to go out and pull my out and measure the tank depth?

[tuckerjt07]

FINALLY...I am done with my swap.



I dropped a new fuel gauge in, fired up the engine and everything works! Temp sender came up to operating temp in a normal amount of time and had a readout of around 125 after 5-10 min. I used a temp gun to compare the temps at the brass T fitting I installed vs the black engine block just below it (where the original temp sender was installed). The difference was consistently around 10 degrees F. In the short term I'm not too worried about this and plan to check it again next time we're on the water for a longer period of time. I found up to three other potential spots to tap into that I may consider moving the single wire sender to in the future: port on the block down under the exhaust manifold on the starboard side of the engine (same as knock sensor but opposite side of engine), two ports near the spark plug wires, one on either side of the engine (but my understanding of these ports is that they'll read head temperature, which will consistently be ~10 degrees F hotter than the stock sender location on top of the block).



Good luck to anyone else out there that might go down this path and feel free to PM me if you have any specific questions - I don't mind at least trying to help (even though I might not know the answer!).





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Do you have some closeups of your depth sounder and check engine light connections. I have a perfect running boat with a constant check engine light and am hoping it's because of wires being crossed.

The one with the empty blade runs to the sounder. The other to the light. The boat is 2000 Maristar 210 VRS.

Sent from my SM-N975U1 using Tapatalk

[01Maristar]

Complete!

I completed my gauge replacement this weekend. I bought an 01 Maristar 210 VRS in May, and on the test drive noticed a couple of the gauges weren't working. Thought I'd be hunting a loose ground or similar... didn't realize I'd be replacing every one. Over the next few weeks I found this forum and realized what I needed to do. And today I'm sure glad I did. Thanks to Jeff and everyone in this thread for the contributions, making this an easy Saturday project.

A few notes... I ordered my gauges and depth sounder in early June, and called Centroid for a new fuel sending unit per the advice here. Mary was a trip and very nice, was able to get me a new custom sending unit within 10 days. However... waiting on depth sounder.. back ordered until late July. Finally came in I found a free weekend to get it done.

The swapout went very easy, just as described here. I had a few additional wires on my MDC and Gauge harnesses, but after reading through I was confident they weren't needed.

Here's what I had to the MDC that I didn't use:
MDC harness:
Orange (constant power?)
Orange / black stripe (switched power? second speedo?)
Blue ?? (marked with an "1" or an "I")

Gauge Harness:
Brown (which I think is related to the rocker switch on the dash for tuning the speedo)

I sealed the ends and coiled all of these up and left them in the dash.

Fuel gauge didn't move until I swapped the sending unit. Direct replacement, even plugged into the existing wire harness. Turned the ignition on and went completely full (only half tank of fuel) and held for about one second, and then snapped right to half. Perfect.

Ran it in the driveway this morning and was able to verify oil and temp working fine.

On to the next project! Probably dual batteries.

On a related note, I have a whole box of medallion parts (6 gauges, MDC 1600, wire harnesses, etc.) that I'll ship to anyone that wants them... just pay shipping and they're yours.

[JRCivic1]

Thank You Jeff d

First, let me offer up a big "Thank You" to Jeff d for providing this information to retrofit analog gauges into an MDC equipped boat... without this, I would NOT have purchased the boat that I have now.

In mid June, I went on a sea trial (test drive in marine speak ?) in a 2001 MasterCraft 19 Skier. The Red/White hull color was just what I was looking for, however, upon initial inspection, I noticed all of the gauge faces were cracked/scratched and were obviously in need of replacement. The seller then informed me that the fuel level gauge didn't work, so I knew I was in for some work to get the instrumentation all up to snuff. Once the boat hit the water, I turned the key and discovered that NONE of the gauges appeared to be working !!! After a few moments of the engine running, the temperature gauge did begin to rise, so that one may be working correctly. Either way, I knew I needed gauge replacements and now I was confident that the MDC was trashed. The cost of replacing these items would have made the deal on the boat out of reach... but knowing that I could convert back to analog style gauges would save enough money to make it work.

I brought the boat home and ordered up a complete set of Chesapeake SS Black gauges from Boatersland.com. I opted to get the Tach with hour meter, and I decided to replace one of the two pitot type Speedometers with a GPS one... this way I could compare the accuracy of the two. I also added a matching Depth Finder to round out the 8-gauge panel.

Once I received my gauges, I followed Jeff d's write up and re-wired the instrument panel. Feeling triumphant, I turned the key to briefly crank the boat and watch all of the gauges come alive. Immediately, I realized that the fuel level gauge still didn't work and the oil pressure gauge didn't work. Rats !!!

Reading beyond the first page of this thread revealed the fuel sending unit compatibility issues, so I promptly ordered the proper length (11.5") WEMA SSL two-wire 33 ohm full/240 ohm empty sending unit. Once installed, the fuel gauge worked.

Next, I pulled the oil pressure gauge back out to see if I had made a mistake in the wiring... all looked good there. I tested continuity between the signal post on the back of the gauge and the oil pressure sending unit on the block... good tone, so the wire is good. This means that the sending unit is bad or the gauge is bad. I ordered both from Boatersland.com just to be safe, and am currently waiting for those parts to arrive. Fingers crossed that this will finally get me perfect.

[BGcraft]

Gauge Tech Notes/Diagrams - and bonus mini rant

Thought <this doc> might be useful...don’t remember seeing it during the many times I’ve perused this thread. Many thanks to the OP and the add’l intel posted here- it’s been super helpful.

So for me, gauge replacement project this winter after learning from local MC dealer: Medallion gauges are $250+ (each), are un-returnable, and the service dept. is unwilling to work on legacy wiring and gauge issues prior to 2008 hulls. Cherry on top...the MMDC box might be faulty and need to be replaced for $800+, however, the dealer touch that either or let you return. Very frustrating and disappointing to be left to fend for myself. Feel like loyal customers and a fan base that takes pride in maintaining their boats (and reps the MC brand name) should receive more service/support for legacy MC offerings.

I did call Knoxville, TN MC for a goof- super cool/helpful service dept. They will re-wire with Faria gauges and a new harness for ~$1800. I may tow it there and pony up if I jack up my gauge project this winter.

no affiliation here- but I am diggin these marine gauges from <autometer>. All the secondaries are fairly inexpensive. No 4” tach but may try and retro-fit their 5”. Don’t need speedos as I’m running PP stargazer and gps speedo. Just looking for something clean looking as the Faria and Sierra gauges don’t match my application.

Ski hard, bourbon up, and be well.

B.

[Vtliskey]

Anybody that has done this conversion by chance have their old 9.75" fuel sender they'd be willing to part with?

[Tsumi]

I might have one.

[Vtliskey]

Tsumi....pm sent

[gwozhog]

Has anyone done the analog conversion on a 2005 or newer mastercraft. The guages are flush mount and have no bezel. If so who sells them?

[prostar205]

Following - I think this may be my next project.

[gwozhog]

Decided to bite the bullet and replace them with OEM guages again. Good news though is im buying all red medallion guages instead of black so it should look pretty badass with my viper red gell inside hull and I also get to keep my hour meter, depth and temp guage. Buying them straight from Medallion too.

[prostar205]

Decided to bite the bullet and replace them with OEM guages again. Good news though is im buying all red medallion guages instead of black so it should look pretty badass with my viper red gell inside hull and I also get to keep my hour meter, depth and temp guage. Buying them straight from Medallion too.

Can you provide a link? I need a new voltmeter for my 2002. MCPARTSDEPOT wants my first natural born son or $415. Seem kind of excessive.

[Steel Horse]

Following, May do this as well.

[shullc]

Much like others have posted this write up was perfect. Thanks for doing the leg work Jeff. We completed the switch over last night and everything works great. We went with the Faria gauges and had a few questions. Has anyone found a clock that goes with it that isn’t $120? Other question is we have the old gauges and two MDC units. Would like to sell but would want to test to make sure they work 1st since they worked most of the time like people have said. Anyone know how?

[DanMahx]

The original clock should work without the MMDC, unless it's no good to begin with. It just runs on 12V. When I swapped the gauges on my 2003 209 the clock was bad. I got an NOS one from Great Lakes Skipper and used the original dial face to match, almost, the new Faria gauges.