m90a Help

Following on from earlier threads, I purchased the above outboard partially stripped and in unknown order (it came "free" with the boat but was apparently in working order and was stripped to paint the block which has flaking paint).

having purchased the wiring loom I now have everything wired up to the forward controls, starter motor back on, oil tank back on filled and bled at the oil pump and hooked up running on pre-mix just to be safe.

Couple of questions which I cant find from the manual or parts list catalogue (its a 1995 90hp M90a power trim/tilt):

1. Battery Negative, does this go to the starter motor? they usually do but the parts manual doesn't shows it going to the start but what I think is the earth point on the motor? I put it to the earth point and everything seems to work but when cranking the motor over the negative wire gets warm.
2. Trim only goes down and not up, no click when pressing the up on the controls. I am not overly worried as long as the trim motor works its one less think to fix and guessing its just a relay or maybe the switch?

TIA

Any block or starter ground is fine for the battery ground cable. It came from the Factory attached to the block near the starter solenoid.
If the battery cable gets warm, it has too much resistance. It might be corroded, the ends mught have oxidation, or the wire might just be too small.
If the TT does not click, troubleshoot the switch and solenoid. May have a bad solenoid.
You should get the Factory service manual to get everything setup properly.

Thanks again Paul,

Leads were just old ones I used just to see if the motor would do anything! I will be making up new leads but wanted to check mounting location first the block by the starter solenoid is where I attached it so that all makes sense.

I have the service manual but this wasn't overly helpful but I will check again thanks

Just to update, Yesterday I made up a new set of battery cables and attached the ground to the engine ground terminal attached everything and she fired right up (first time in 3-4 years!)

The fault with the trim has been traced back to the switch on the throttle controls and I am not sure if the switch can actually be replaced or whether I need to wire in a stand-alone switch.

That is the special switch that fits into the RC handle.