74 merc thunderbolt 50 hp tilt trim installation

[duckhunter138]

ive got a 50 hp thunderbolt. i bought a tilt trim system for it for 100 bucks off of an older gentleman who said it would fit on there. does anyone know where i can find some reference diagrams or pictures to go off of for this install? also a wiring diagram for the switch to the motor as the guy cut the purple wire for the trim and was using a 3 way switch to just run the tilt. also how does the trim portion on this system work? normally you have the big cylinder runs tilt and the two smaller powerfull ones run the trim, this is a 2 cylinder 4 hose system. any help is appreciated. thanks.

mike

 

[merc850]

Re: 74 merc thunderbolt 50 hp tilt trim installation

Here's the wiring diagram
and the mounting setup

the hoses should have some slack so they can move when trim is operated.
The trim limit switch might be toast, you can bypass it and run that way.
Make sure the tilt pin is in at the closest hole to the transom, do not run without it.
Also the unit should be bled for proper operation.

 

[duckhunter138]

Re: 74 merc thunderbolt 50 hp tilt trim installation

thanks so much for the info. I dont know where you guys come up with this info, ive looked everywhere to try to find it. Much appreciated. p.s. when you say trim pin your referring to the one thats on the motor now, not the pin on the tilt trim assembly i bought right? because there is a pin in the bottom of the cylinder bracket roughly the same size as the trim pin that is frozen in on one side but the guy said i could just bolt it through the transom instead of using this pin?
would this be ok?

thanks,
mike

 

[merc850]

Re: 74 merc thunderbolt 50 hp tilt trim installation

It is a good idea to buy a Mercury manual for future repairs and info like oil/gas mix (50/1 for that motor), and yes it is the pin that goes thru the holes in the clamp bracket. The motor has to be bolted to the transom using the slots at the bottom of the clamp B and the slots in the power trim brackets. Use SS bolts and Nylock nuts don't rely on just the thumbscrews!

 

[duckhunter138]

Re: 74 merc thunderbolt 50 hp tilt trim installation

Yeah thank you, I've got the manual for it Lotta good info but nothing on the tilt unit. The install is going good though just going to leave that frozen pin in it and put all four bolts through the tilt brackets. And I put the bolts in my motor bracket when I installed the motor. Gonna be great to have tilt trim on this thing. One more question, the purple wire is just wired so it acts as a cuttoff when a limit switch is activated? Meaning if I don't use the purple wire I just have to be careful not to raise the motor out of the water when its running right?

 

[Moody Blue]

Re: 74 merc thunderbolt 50 hp tilt trim installation

This may come in handy at some point. Its a copy of the original installation manual for the old type-1 PTT units.

https://picasaweb.google.com/Smig06/PTTManuals#