MDC Repair

[Eagleboy99]

I think OP has 4" gauges which means you have dozens of choices.  If 5", then not so much.  Frankly, I like lifetime warranteed accurate  over the silly OEM garbage.  An full analgue set is les than a new computer and gauge set.  Way less.  Crazy less if you do it yourself with 4"

[jhardwood]

I did the resolder this weekend on the MDC and all gauges (except disconnected speedos) are functioning properly.  Nautic Logic NPS2 is ordered :).   One further question:  Once I remove the pitots, what did you use for material type to plug the screw and tubing holes in the transom?

[Bozboat]

8 minutes ago, jhardwood said:

I did the resolder this weekend on the MDC and all gauges (except disconnected speedos) are functioning properly.  Nautic Logic NPS2 is ordered :).   One further question:  Once I remove the pitots, what did you use for material type to plug the screw and tubing holes in the transom?

MarineTex

Edited September 17, 2019 by Bozboat

[Eagleboy99]

1 hour ago, jhardwood said:

I did the resolder this weekend on the MDC and all gauges (except disconnected speedos) are functioning properly.  Nautic Logic NPS2 is ordered :).   One further question:  Once I remove the pitots, what did you use for material type to plug the screw and tubing holes in the transom?

You could wire up LED lights where the pitot tubes were.

[Eagleboy99]

I have not yet decided what to do with my vestigial pitot tubes.

[asnowman]

6 hours ago, Eagleboy99 said:

You could wire up LED lights where the pitot tubes were.

That's what i would do!

7 hours ago, jhardwood said:

 Nautic Logic NPS2 is ordered :).   

I put the nautic logic in our 2011, it was a huge improvement.

[justgary]

13 hours ago, Eagleboy99 said:

I have not yet decided what to do with my vestigial pitot tubes.

I haven't even removed the pitots.  I just leave them up all the time.  I'm not really sure I need any LEDS....

[jimskiwithsoul]

Hello All,

I have a 1999 Moomba Kanga.  Gages worked for 20 years without issues.  Last year tach wen weird, would work then not.  Things progressed to other gauges and now temp and oil fluctuates, tach is pretty buried at the 6 o'clock position and voltmeter fluctuates from 9 to 10 volts.  Boats is operating well other than these false reads from the gauges.

 

My questions are: 

 

Is this possibly a problem in the mdc or the power going to it?

 

What would others do with this challenge?

[UWSkier]

Could be corrosion in the wiring. Check all grounds. If that all checks out then start digging into the MDC. If your pitots were ever winterized with compressed air, you may have gotten water up into the computer. 

[jimskiwithsoul]

This is a naive question, but when I check for grounds where do I find these: in the harness?  Would a volt meter identify ground troubles if they are off i.e., below 7 volts?

[RedWakesetterVLX]

10 hours ago, jimskiwithsoul said:

Hello All,

I have a 1999 Moomba Kanga.  Gages worked for 20 years without issues.  Last year tach wen weird, would work then not.  Things progressed to other gauges and now temp and oil fluctuates, tach is pretty buried at the 6 o'clock position and voltmeter fluctuates from 9 to 10 volts.  Boats is operating well other than these false reads from the gauges.

 

My questions are: 

 

Is this possibly a problem in the mdc or the power going to it?

 

What would others do with this challenge?

Sounds like either a voltage issue or the MDC is going dead. Mine dies last year after 20 years...

[surfjeffv]

Fellow Malibu owners, thanks for all of the posts related to the MDC issues and possible causes and repairs!   I spent some time working on my MDC PN 6607-20006-01E, 2-19-1999 for the past few days after my gauges abrubtly stopped working all at the same time.  Did all of the testing and determined the issue was, in fact, the  MDC.  I contacted Medallion after visiting their website @ medallionis.com Medallion's website and spoke to Scott in technical services.  Together we confirmed that the MDC was dead.  I had already remove the top cover and re-flowed the solder on the two main connectors despite no visual appearance of damage and that did not resovle the problem.  I was also able to order the replacement part directly from Medallion for considerably less than Bakes is selling it for.  The replacement part is PN 6607-20008-01 and was $345.75 plus a flat $20 shipping and it will take about a week to two weeks to get.  Bakes is selling the same part for $599 plus tax and shipping.  I also took some pictures of the "Cannon" connector at the back of the engine showing its location and what it looks like when disconnected.  Some have said that this connector can be plugged in multiple ways, however, I found that not to be true based on the positive and ground pins being much larger than the other 7 pins in the 10 pin connector, only  9 of which are used.  

 

Edited August 21, 2020 by surfjeffv
deleted some superfluous text now that images could be added

[Eagleboy99]

1 hour ago, surfjeffv said:

Fellow Malibu owners, thanks for all of the posts related to the MDC issues and possible causes and repairs!   I spent some time working on my MDC PN 6607-20006-01E, 2-19-1999 for the past few days after my gauges abrubtly stopped working all at the same time.  Did all of the testing and determined the issue was, in fact, the  MDC.  I contacted Medallion after visiting their website @ medallionis.com Medallion's website and spoke to Scott in technical services.  Together we confirmed that the MDC was dead.  I had already remove the top cover and re-flowed the solder on the two main connectors despite no visual appearance of damage and that did not resovle the problem.  I was also able to order the replacement part directly from Medallion for considerably less than Bakes is selling it for.  The replacement part is PN 6607-20008-01 and was $345.75 plus a flat $20 shipping and it will take about a week to two weeks to get.  Bakes is selling the same part for $599 plus tax and shipping.  I also took some pictures of the "Cannon" connector at the back of the engine showing its location and what it looks like when disconnected.  Some have said that this connector can be plugged in multiple ways, however, I found that not to be true based on the positive and ground pins being much larger than the other 7 pins in the 10 pin connector, only  9 of which are used.  I can't seem to figure out how to add pictures, but can provide to anyone who might be interested.

 

Join TMC or put the images on a third party site like IMGBB, Dropbox etc.  As for the PN, note that each one is  custom made and what works in a 99 may not work in another 99 or another year of boat.  I would be real careful on how you winterize the MDC since water ingress is the big thing that blows them up.

[surfjeffv]

@Eagleboy99, thanks for the reply.  I am a member of TMC since 2009 I just haven't posted anything!  As for the PN, that is a very common PN for many Malibu models from the late 90's to early 2000's.  No need for me to winterize since I live in SoCal.

[surfjeffv]

1 hour ago, surfjeffv said:

@Eagleboy99, thanks for the reply.  I am a member of TMC since 2009 I just haven't posted anything!  As for the PN, that is a very common PN for many Malibu models from the late 90's to early 2000's.  No need for me to winterize since I live in SoCal.

@Eagleboy99, I guess you have to be a "supporter" to add photos easily!  I am now a paid supporter!  This is a great resource/forum!

[mainekneeboarder]

Well Round 2! My gauges started the same symptoms this summer and then finally got to the point I really had to pull/prey at the plug to make them work again. Pulled the MDC apart last week and re soldered the same pins, put a few hours on it this weekend and all is great again. My oil pressure gauge had started wondering again early summer and now is steady after repair also. Well worth the time for a 5-6 year fix!

[CDOBU]

Anybody have experience with the TRD-MDC conversion kits?  Basically replaces that entire MDC-1600 system with GPS speedo and digital gauges.  I have blown 5 ignition control modules on my 2001 Malibu Sunsetter VLX, which apparently can be caused by a faulty tach, which at times has gone from not working to working, now have a blown voltmeter and fuel gauge that is flaky as well.  Thinking it would make sense to replace the whole instrument shooting match, rather than trying to trace down where all these individual problems are coming from.

[Eagleboy99]

They are great. Ron has made hundreds for Malibu, MC, etc.  Nice retorfit kit.  I have never heard of a faulty tach blowing  ICMs.  I suspect the other guages are just dying from old age.

[RedWakesetterVLX]

51 minutes ago, CDOBU said:

Anybody have experience with the TRD-MDC conversion kits?  Basically replaces that entire MDC-1600 system with GPS speedo and digital gauges.  I have blown 5 ignition control modules on my 2001 Malibu Sunsetter VLX, which apparently can be caused by a faulty tach, which at times has gone from not working to working, now have a blown voltmeter and fuel gauge that is flaky as well.  Thinking it would make sense to replace the whole instrument shooting match, rather than trying to trace down where all these individual problems are coming from.

I have them as well and highly recommend. 

[CDOBU]

Thanks, guys.  I have ordered mine, will keep y'all posted.  That MDC-1600 is clearly buggy whip technology, was designed to make those old fashioned speedos work with the newer gauges.  Problem is, once it goes south, there is no way of knowing where all those signals/voltages are going.  With a blown voltmeter, suspected blown fuel gauge, flaky tach, 5 blown ICMs, odds are good that MDC-1600 is the culprit, but there does not seem to be anybody out there who wants to trouble shoot and/or repair the damn thing, and to replace that, along with all those faulty gauges is well over $2K for the parts alone, just to bring that buggy whip technology back!  For about $900, the TRD-MDC kit includes all new digital gauges, including a GPS speedo, and it entirely eliminates the need for that MDC-1600. 

Last question, have any of you installed Perfect Pass (or any other speed control system, like Zero Off) along with the TRD-MDC conversion kit?  I was hoping to do that for less than the cost of the normal Perfect Pass "Star Gazer" system (another $1,200) as the GPS speedo would have the GPS output that PP system needs, just curious if that could be done.  Ron from TRD is out on vacation this week, but I expect he could answer this question, just curious if any of you have set up your boat for both TRD-MDC conversion and speed control.

[Eagleboy99]

I have PerfectPass CRUISE (RPM only) and it is fine for open water slalom. It merely uses the grey RPM wire (and power of course).  You could look for a used PerfectPas system, but then you will be stuck with an extra gauge.  Otherwise, break out the wallet.  You can order a short kit that leaves room for the PP display.  

[RedWakesetterVLX]

3 hours ago, CDOBU said:

Thanks, guys.  I have ordered mine, will keep y'all posted.  That MDC-1600 is clearly buggy whip technology, was designed to make those old fashioned speedos work with the newer gauges.  Problem is, once it goes south, there is no way of knowing where all those signals/voltages are going.  With a blown voltmeter, suspected blown fuel gauge, flaky tach, 5 blown ICMs, odds are good that MDC-1600 is the culprit, but there does not seem to be anybody out there who wants to trouble shoot and/or repair the damn thing, and to replace that, along with all those faulty gauges is well over $2K for the parts alone, just to bring that buggy whip technology back!  For about $900, the TRD-MDC kit includes all new digital gauges, including a GPS speedo, and it entirely eliminates the need for that MDC-1600. 

Last question, have any of you installed Perfect Pass (or any other speed control system, like Zero Off) along with the TRD-MDC conversion kit?  I was hoping to do that for less than the cost of the normal Perfect Pass "Star Gazer" system (another $1,200) as the GPS speedo would have the GPS output that PP system needs, just curious if that could be done.  Ron from TRD is out on vacation this week, but I expect he could answer this question, just curious if any of you have set up your boat for both TRD-MDC conversion and speed control.

I have PP Stargazer I run with the TRD system (4-1 and RPM)  I just replaced my speedo with the PP gauge.  

You mentioned digital gauges.  The TRD gauges (Faria) I have are analog not digital...I didn’t think he offered a digital gauge replacement. Are you referring to the GPS speedometer?

Edited October 14, 2020 by RedWakesetterVLX

[CDOBU]

Yes, as I figured that TRD-MDC GPS speedo is a digital device, which would hopefully give output needed for the speed control.   Just wondering if there is a speed control kit out there (PP, Zero-Off, etc.) that would work with that TRD-MDC conversion kit.  Ron is out this week, I'll check in with him next week, let y'all know if I find anything.

[CDOBU]

BTW, I talked to another tech yesterday at Singleton Marine, where I bought my boat.  Very helpful guy, said the distributor is likely the culprit for all those blown ICM's, which makes perfect sense.  The old distributor body magnet gets worn, sends flaky voltages to the ICM, which could easily blow the ICM.  He recommended replacing the entire distributor with a performance distributor/coil set up, which I am about to do.  Should also help start up and top end performance.  Anybody ever use Summit Racing's distributors?

[Eagleboy99]

34 minutes ago, CDOBU said:

Anybody ever use Summit Racing's distributors?

Unless they are marine you shouldn't. Marine distributors always have a screen over the breather vent hole in the base of the distributor. Automotive distributors usually have a vacuum advance which no marine distributor uses.