Another Gauge Question

[RudeDog]

I did not want to highjack Wally's thread so I started a new one.

I just got a new-to-me 1999 Launch Pro. I like the boat except I'm already having a problem. My nearest Skiers Choice dealer is 4hrs away so I would like to see if I can fix this myself.

The water temperature (engine not lake) gauge is not working. I pulled the gauge out of the instrument panel and took a look at it. There is no indication who the manufaturer is. The face is black with white numbers and it reads from 80 to 240 degrees (the only other number is 160 degrees at the halfway point). The sender wire has a five hole female flat plug that plugs into the five pins in the back of the gauge. Does anyone know where I can get a replacement? I'm assuming Supra got these gauges from one of the main gauge manufactuers.... right??? I've searched the web and looked at Faria, Teleflex and VDO gauges but I can't seem to find one that matches this gauge and I'm not sure if any of them have this connection type. Any help would be appreciated!

[99 LAUNCH]

My boat is the same model. I also have temp gauge problem. I think it is the sending unit on the intake manifold not the gauge. I mounted a mechanical gauge to the engine until I order new sending units.

[RudeDog]

Thanks for the reply. What brand and size engine mounted temp. gauge did you buy? Where exactly is the sending unit located? Do you have the 325 HP MPI Indmar engine?

Thanks!

[99 LAUNCH]

My boat has a 325 hp vortec 350 with a carb. I bought the gauge at O,Reilly auto parts. It,s a white face gauge looks like an Auto Metter gauge. The gauge was about twenty five $. I mounted it to the front of the head with a bracket with a ~ s ~ bend. The sensor mounts in to the head on either side of the engine. There is a plug in the side of the head that has to be removed. the plug is almost the size of a 3/8 rachet . You can grinde a 3/8 extension a little and it will work. make sure to use teflon tape on the fitting threads or you will have leaks. I am going to mount one more gauge for the other head on mine. This way I can read the temp off both sides of the engine. My boat is direct drive so its easy to lift the engine cover up from the drivers seat to check the temp every once -n- a while. My motor never gets over 180. mechanical gauges are very acurate. This project took about 2 hours. Let me know if I can be of any more help. GOOD LUCK !!

[thegorilla]

Hi guys,
Did you ever figure out what was at fault: the sender, gauge, or control unit under the dash?

I just bought a 1999 Santera with the 350MPI and I think I'm having a similar issue. My temp and speedo don't work. The engine never actually runs hot, but I'm the paranoid type and want to know the real temp, just in case... Sounds like I might just replace the factory gauge with an auto meter elec or something.

Do you know if the existing gauge is compatible with an aftermarket electrical sender?


Seems like I've been reviving old threads since I joined the board...

-orn

[docdrs]

If its just one gauge then the gauge is probably bad, if its all the gauges ,then it could be your mdc unit under the helm

[TX skier]

They are probably Medallion Gauges. Seems they get all the info from the MDC. Google Medallion Instruments for more information.

Good luck,
David

[thegorilla]

OK, I googled Medallion and it appears that I have Series II gauges with an MDC. I found this troubleshooting guide online, so I think that's my next step.

[PDF] Troubleshooting Guide for Medallion II Series Instruments Definitions
www.epicmarine.com/docs/MDCtrouble.PDF

I have a Hydrophase Ridesteady cruise control system waiting to be installed, so I don't care if the speedo doesn't work, but I need a temp gauge.