Need to re calibrate my temp gage

[maproy99]

I was having problems with my temp in my engine. Long story short (month long) I have gotten everything worked out but now my temperature gauge is reading too high. I have a cold, normal, and hot gauge. The gauge reads my motor is burning up, but it is sitting around 140-145 degrees off a 140 degree thermostat. I want to set this as the normal operating temp on the low side, since it is as low as my engine should be. The gauge is starting at about the middle then climbs up and stops right before it maxes out the gauge. I would like to know, is it possible to adjust the gauge to this, or will I have to get a new one if I can find one? It is not a necessity but it would be nice to have fixed. This is a 1974 engine ford 302-v8 mercruiser conversion. Anyone have any ideas?

 

[cr2k]

Re: Need to re calibrate my temp gage

You could add a resistor in line. Boat temp gauges are notoriously off.

 

[Don S]

Re: Need to re calibrate my temp gage

Probably either a bad sending unit on the engine, or a bad gauge. Have you checked the sending unit to see if it has the correct ohms reading for the temp? Since you have a conversion engine, where did the sender on the engine come from? Not all senders are the same.

If you have the old engine, take the sender off it and try it.

 

[achris]

Re: Need to re calibrate my temp gage

..... The gauge is starting at about the middle then climbs up and stops right before it maxes out the gauge. ...

"Starting at the middle"... When the engine is dead cold? Sounds like a bad gauge or sender. Disconnect the sender wire and see if the gauge reads the same. If it does then just go out and find a gauge you like that is '33-240 ohms'. Fit that and all your problems should be solved.... If the gauge does drops back to the left (COLD) when you disconnect the wire, then replace the sender.

Chris......

 

[maproy99]

Re: Need to re calibrate my temp gage

I think I know what my problem is. There are 2 different temp senders for this engine. One is for the type of gauge I have, the other is for a 110-210 degree gauge I believe. Guess which one I think I ended up with? I've ordering the other one and I'm going to see if that fixes it.

 

[tpenfield]

Re: Need to re calibrate my temp gage

My idea is that the gauge and sender are not compatible. The 'other' sender on the engine *may* be for the overheat alarm. so, check that out as well.

 

[maproy99]

Re: Need to re calibrate my temp gage

My idea is that the gauge and sender are not compatible. The 'other' sender on the engine *may* be for the overheat alarm. so, check that out as well.

not compatable since it is for 2 different gauges, that is why I'm ordering the other one, since I just saw a number for the sender and ordered it, not knowing 2 different ones worked.

Sent from my phone.