Going to look at a 1900SC this weekend.

[ss3964spd]

You could, but of course verify power to the gauge first. If you have power to the gauge you could try to remove the wire from the top of the tank sending unit and then ground that wire to something on the engine or to the battery. If the gauge works the needle will move. If it does, you have a ground problem or sending unit problem.

And oh, happy to help!

[mmwjr]

Yes that will show it provides the proper resistance range and you can see that the gauge moves from empty to full.

What it wont prove is whether the float is working correctly in the tank.'

what is the issue with it?

[bicklebok]

It's just not giving a reading at all. I guess I was trying to jump the gun and go straight to the sending unit, but as suggested, I need to make sure there is power going to it first.

[mmwjr]

Do as Dan said try grounding the sender then remove it to see if the gauge moves.

[bicklebok]

Thanks for the tips.

Heres what I have so far. I tried grounding the wires that connect to the sending unit and nothing changed.
When i turn to switch on, the fuel gauge jumps to below E. It normally sits around E with no power to it. Not sure if that tells you anything.
I measured the voltage at the connectors that connect to the sending unit. It measures about 1 volt.
I tried to measure the ohms at the sending unit. Occasionally my multi meter would bounce a reading for a second before losing it. I tried everything I could do to get a good connection and I think I eventually did. It would still only bounce to a reading occasionally

I can see on the back of the gauge itself it has been worked on because the wires connecting to the guage are just stripped wires.

The purple wire is power in and the pink wire is power out to the sending unit....I think

[mmwjr]

When ohming the sender the power has to be off. Remove both wires from the sender then measure the resistance.

Remove the sender wire from the back of the fuel gauge. Turn the key to run and see if the meter moves, then use a wire and ground the sender terminal of the gauge and see what it reads.

[bicklebok]

Originally Posted by mmwjr

When ohming the sender the power has to be off. Remove both wires from the sender then measure the resistance.

I did this already.

Remove the sender wire from the back of the fuel gauge. Turn the key to run and see if the meter moves, then use a wire and ground the sender terminal of the gauge and see what it reads.

Good idea!!! Thanks!

[bicklebok]

I was going to ground the output terminal at the back of the gauge today but I measured the voltage first. It was about 9 volts if I remember correctly. Isnt that too high? Im thinking if I ground it out I will blow a fuse.

I also checked voltage at the terminals that connect to the sending unit with a better probe. It was fluctuating between 3 and 8 volts.

[mmwjr]

The inductance of the gauge should limit the current so the fuse won't blow. You can use a resistor to do this if you want to limit the current further. Try 200 ohm at 1W to play it safe.

[bicklebok]

I have been researching the voltage on the output side of the gauge and coming up with very little information but I think that voltage may be correct.

I think tomorrow i will just ground the connection and see what happens

Im also trying to get ready to adjust the timing. That bolt holding the distributor in was hard to get to!

[bicklebok]

I grounded out the fuel gauge today and it pegged to full. Tried to test the ohms on the sending and never got any reading.

The sending unit is manufactured by Wema Systems. I measured it and its 8" deep. About to research for a new one. Any suggestions?

[mmwjr]

Any manufacture will do, some units have adjustable arm lengths.

There is another style that had a float that rides up and down on a shaft.

[bicklebok]

Hey Mike and Dan, any other experts,
I have a problem setting the timing because there is a big rust spot on the harmonic balancer where the 10 degree BTC is.

I can measure the increments in the legible units to be able to mark where the 10 degree mark should be. My problem is getting the harmonic balancer to be where i can see where to mark. How can i rotate the engine with a tool?

Thanks!

[bicklebok]

I got it! It finally happened to stop where i could get to it. I took a tape measure and measured around and marked on the harmonic balancer where the 10 degree mark should go.

[mmwjr]

You can use a socket on the balancer center bolt but only turn counter clockwise so if the engine is tight you will only loosen the bolt and not break it off.

Measure the diameter of the balancer and you can buy a timing tape from Summit racing or other sources.

[bicklebok]

Thanks again for the tips!

[bicklebok]

Hope you guys are having a womderful holiday weekend!

I have an update on the fuel gauge. I know the sending unit was bad; I verified it with the multi meter. I installed a new sending unit today which did not fix the fuel gauge.

Several days ago I was able to get voltage at the sending unit connection but today I did not. I took the pink wire loose at the fuel gauge and connected my multi meter to both ends of the pink wire. There is no continuity.

So I guess my question is where will I run a new wire along the starboard side of the boat? Are the wires running down low or higher near the steering cables? I dont really see an access place?

Thanks guys!

[mmwjr]

Thanks hope you're enjoying the holiday weekend as well.

Not sure how the wires were ran. Yep sounds like you need to pull a new one.

[bicklebok]

Happy 4th!
I now have a fuel gauge. Ran a new wire from the dash to the tank.

Next on the agenda: i thing i have water in the trim resovoir.

One step at a time, and with you guys giving advice, Im gonna get this boat in top top shape!

[mmwjr]

How do you eat an elephant?

One bite at a time.

happy 4th