Can I calibrate the trim gauge somehow?

[asdasc]

On my 1990 Chriscraft 20', with an OMC 4.3L HO, the trim gauge on the dash is wrong. All the way down it reads about 1.25, when it should read 0. I have the service manual, and it doesn't say anything in there about it. It may be an adjustment on the gauge, not the outdrive? If so, what is the procedure? I boat often in shallow water and want to make sure that I am not cruising along with the outdrive up too far.

[HT32BSX115]

Howdy,

Those trim gages are simply a standard D'Arsonvalmeter at the panel and a variable resistor in the drive.

Because the variable resistor can get wet, corroded, or fouled with "stuff" the repeatability of position and display is not very reliable.

They're pretty good for telling you you're all the way down (and you verify because you usually hear a clunk)

And they're pretty good at telling you you're all the way UP (and you verify because the pump slows down.)

When you're running on plane, your range of operation is based on performance but it's a VERY small range where it works good. The gage is pretty much useless for repeatability.

(I never look at mine except when I want to know for trailering and I want it all the way down for holeshot)

You can usually do ball park adjustment by turning the sender CCW or CW on the drive if it's mounted with slotted holes. I can't remember if mine did on my old Cobra. It didn't work anyway.

[Levinz11]

Howdy,

Those trim gages are simply a standard D'Arsonvalmeter at the panel and a variable resistor in the drive.

Because the variable resistor can get wet, corroded, or fouled with "stuff" the repeatability of position and display is not very reliable.

They're pretty good for telling you you're all the way down (and you verify because you usually hear a clunk)

And they're pretty good at telling you you're all the way UP (and you verify because the pump slows down.)

When you're running on plane, your range of operation is based on performance but it's a VERY small range where it works good. The gage is pretty much useless for repeatability.

(I never look at mine except when I want to know for trailering and I want it all the way down for holeshot)

You can usually do ball park adjustment by turning the sender CCW or CW on the drive if it's mounted with slotted holes. I can't remember if mine did on my old Cobra. It didn't work anyway.

Diggin the avi and sig

[HT32BSX115]

Diggin the avi and sig

My Dad worked for Tidewater Associated Oil Company (Flying-A!!)

[sam60]

Howdy,

Those trim gages are simply a standard D'Arsonvalmeter at the panel and a variable resistor in the drive.

Because the variable resistor can get wet, corroded, or fouled with "stuff" the repeatability of position and display is not very reliable.

They're pretty good for telling you you're all the way down (and you verify because you usually hear a clunk)

And they're pretty good at telling you you're all the way UP (and you verify because the pump slows down.)

When you're running on plane, your range of operation is based on performance but it's a VERY small range where it works good. The gage is pretty much useless for repeatability.

(I never look at mine except when I want to know for trailering and I want it all the way down for holeshot)

You can usually do ball park adjustment by turning the sender CCW or CW on the drive if it's mounted with slotted holes. I can't remember if mine did on my old Cobra. It didn't work anyway.

http://www.engineersedge.com/instrum...l_movement.htm

Cool info! You know some stuff!

[asdasc]

OK, thanks for all the info.

If I had a deep lake, I wouldn't need the gauge either, but the area around the cottage is called 'The Flats', and it is that. The water near the dock is only 1-3' deep, and there are many canals I need to frequent which are also very shallow, so it would be great to be able to where the critical point is so that I can raise my outdrive and still creep along without wrecking the gimbals.

How much damage would I be doing if I did this?

[HT32BSX115]

OK, thanks for all the info.

If I had a deep lake, I wouldn't need the gauge either, but the area around the cottage is called 'The Flats', and it is that. The water near the dock is only 1-3' deep, and there are many canals I need to frequent which are also very shallow, so it would be great to be able to where the critical point is so that I can raise my outdrive and still creep along without wrecking the gimbals.

How much damage would I be doing if I did this?

You know, I don't remember if my cobra had a trim limit switch. But you're generally safe to run the drive up with the gimbal angle no higher than the MAX equivalent left/right angle as long as you keep the water pickup ports covered.
IDLE ONLY!!

My Bravo III has a trim limit that I set for just that purpose so I don't have to run back and look.