Johnson 90 1984 Trim/Hour Gauge Wiring???

[NZjohnson90]

After a year of tinkering on the driveway trying to beg borrow and steal as much as possible for my super budget glastron resto, It is nearly ready for the water.

I just have 1 small issue.

The trim gauge and hours gauge wires.
These were taken straight of the previous boat, were all working at the time and nothing has been changed so they should still work but I don't know which wires go to which terminal.

Trim Gauge has 3 terminals G, S, I.
Hours Gauge has 2 terminals +, -

I have 3 wires coming out of the Tacho (which works fine) Purple, Black and Blue

and I have 2 wires that come from the control Lever Tan and White, Black and Tan(or white?)

Have had as stated on this forum somewhere.
purple I
Tan/White S
Black (also tried back/tan) G

but the gauge just seen kinda erratic, there is some life in it but the needle just seems either at one end or the other of the scale and not show any accurate reading in between.

I tested the gauge as suggested by crossing the G and S terminals and it apparently works.

I assume once I get the trim wires right the the hours must be the 2 leftover so I'll deal with them after.

I'm new to boating and new to this forum so any help would be much appreciated.

All the rest of the wiring works and the motor seems to run sweet. (does just over 1000rpm sound right for tickover?? I think it might settle down to 900rpm when it's warm, is this normal.

Cheers

 

[NZjohnson90]

Re: Johnson 90 1984 Trim/Hour Gauge Wiring???

OK so like I said im new to this. Just thought to try the obvious, and had a go at moving the sender unit by hand to see what the gauge does.

Seems to me that the sender unit is at fault, if you move it up n down very slowly and smoothly, the gauge seems to move properly for a little while and then jump erraticly to the other end of the scale and back again if you follow what im saying?

Does anyone think it might just be dirty or clogged up contacts in there. is it easy to open the unit up and give it a clean out without breaking it?
I also have the black n white wire from the t and t controls that seems to do nothing?

Any advice appreciated

 

[jonesg]

Re: Johnson 90 1984 Trim/Hour Gauge Wiring???

The trim guage is mostly seen as a useless gadget around here, the wiring is put to better use for a temp or water pressure guage. The sender is expensive , not worth spending money on.

Hr guage just runs a clock whenever ignition is turned on, the purple wire is switched pos v. Any black will work for ground.

 

[NZjohnson90]

Re: Johnson 90 1984 Trim/Hour Gauge Wiring???

Cool, Thanks for that, I was coming to the same conclusion myself. Would have been nice to be all working properly but never mind. Hopefully the big launch next week or so.