Temp gauge not working

[Leirhiht]

I posted this in general chat originally with no replies. Not trying to flood this thread. One more shot..
Got an 08 moomba mobius lsv with the 325 assault engine. Took it out Saturday and it overheated, shUT engine off immediately, found out it was loose raw water pump cover when i replaced the impeller, tightened the cover and went surfing. Ran it about 3 hours and the temp gauge didn't seem to work after it was overheated, but ran fine the rest of the day. Did I damage a temp element or sensor? Where is the sensor or element located and where can I buy one?

[mmandley]

I would call your local dealer for a Part # or check Skidim i think it is, also Cyndi at Atlanta Marine is really good.

Location is or should be on the top of intake facing the rear of boat < front of engine > near the top by the thermostat.

Hopefully this Link works to a picture.

In this picture its on the Left right by the Hose that says Master Craft on it in Blue
This may not be the exact as yours as its a 94 engine but its close enough to show you what your looking for.

http://i639.photobucket.com/albums/uu114/mmandley/Things%20for%20sale/S645001_SM_zpsc4zut2s0.jpg (http://s639.photobucket.com/user/mmandley/media/Things%20for%20sale/S645001_SM_zpsc4zut2s0.jpg.html)

http://i639.photobucket.com/albums/uu114/mmandley/Things%20for%20sale/1994-Indmar-350-Chevy-engine_zpsekd3fhfy.jpg (http://s639.photobucket.com/user/mmandley/media/Things%20for%20sale/1994-Indmar-350-Chevy-engine_zpsekd3fhfy.jpg.html)

[Leirhiht]

I would call your local dealer for a Part # or check Skidim i think it is, also Cyndi at Atlanta Marine is really good.

Location is or should be on the top of intake facing the rear of boat < front of engine > near the top by the thermostat.

Hopefully this Link works to a picture.

In this picture its on the Left right by the Hose that says Master Craft on it in Blue
This may not be the exact as yours as its a 94 engine but its close enough to show you what your looking for.

http://i639.photobucket.com/albums/uu114/mmandley/Things%20for%20sale/S645001_SM_zpsc4zut2s0.jpg (http://s639.photobucket.com/user/mmandley/media/Things%20for%20sale/S645001_SM_zpsc4zut2s0.jpg.html)

http://i639.photobucket.com/albums/uu114/mmandley/Things%20for%20sale/1994-Indmar-350-Chevy-engine_zpsekd3fhfy.jpg (http://s639.photobucket.com/user/mmandley/media/Things%20for%20sale/1994-Indmar-350-Chevy-engine_zpsekd3fhfy.jpg.html)

Awesome! That helps a lot. Thank you

[gregski]

My experience is that these are typically "standard" parts. If you can remove it and take it to the auto parts store, they can probably get you a match. You may need to make up a car as a starting point. A Silverado gets pretty good results.

[lee]

There is two temp sending units in the engine, one is for the ECM and one for the gauge. You will need the correct one.

[Leirhiht]

There is two temp sending units in the engine, one is for the ECM and one for the gauge. You will need the correct one.

Is there a way to tell which is needed? Does anyone think I should replace the t stat too?

[lee]

You take the wire off of one and ground it to the engine and if the needle pegs with the key on that would be the correct sender.

[Leirhiht]

You take the wire off of one and ground it to the engine and if the needle pegs with the key on that would be the correct sender.

OK so I didn't test to see which one I needed, but I just bought the sensor with the stud on top because it was cheap and in stock at my moomba shop. It didn't fix the gauge so now I'm wondering if it is the other sensor, with the electrical pig tail. if that is for the ECM is it possible replacing that sensor won't fix my issue? What else could it be if that doesn't fix my problem?

[Jceclipse01]

This is the one that I needed http://uploads.tapatalk-cdn.com/20160607/2aa21da05c00e4cf15562c1f34184662.jpg

Sent from my SM-G900V using Tapatalk

[Jceclipse01]

Sorry I was thinking oil gauge not temperature. It could be that the gauge is bad

Sent from my SM-G900V using Tapatalk

[Leirhiht]

This is the one that I needed http://uploads.tapatalk-cdn.com/20160607/2aa21da05c00e4cf15562c1f34184662.jpg

Sent from my SM-G900V using Tapatalk

Kind of looks like what I replaced. 24296 but now I'm hoping it's this one. 24297

[Jceclipse01]

The one on the bottom picture is the one that goes to the ecm I think.

Sent from my SM-G900V using Tapatalk

[Leirhiht]

Do those typically go out after over heating? It was working fine until It over heated. I hope it's not the gauge. Seems like a hassle to find and install.

[Leirhiht]

Yes it is for ECM. Is it even a possibility that could fix my problem?

[Jceclipse01]

Give Discount inboard marine a call they'll help you out

Sent from my SM-G900V using Tapatalk

[roosm]

Hi,

I had the same issue with my 2001 Launch SSV (Supra).
To check the gauge, turn on the ignition without starting the engine and ground the S-post of the gauge, that is the send-cable from the sender.
Just ground it between gauge ground and S. This should spike the needle, if it doesn't, check for 12V at the I (ignition) terminal of the gauge.
If you have 12v, but it doesn't spike, bad gauge.

If it does spike, try grounding the other end of the sender cable back at the sender. If grounding this gets it to spike the cable is good.
Test the sender with an Ohm-meter.
If you get the correct ohm-reading, you can google mercruiser temp sender ohm range and probably find something useful, the sender is good.

In my case the sender-test failed, but I took it one step further, I tested the temp of the block it self. If you have a laser temp-gun you can use that.
Mine wasn't warm enough. Turns out the thermostat was stuck open and I never reached operating temp.
Is it running fine with normal fuel economy, then probably this isn't the case. Mine was running fine but with high fuel consumption.

My sender was under the thermostat-housing so I had to unbolt the thermostat housing to get to the temp sender.
If yours is the same you might just as well unbolt the thermostat housing and check the thermostat, if the gauge tests good.

Good luck,
Mike