1986 150 powerhead fit on 1977 175 midsection?

[Cogburn]

My Buddy fried the #5 piston on his 1977 175 #4589143. I have a 1986 150 that runs but the rest is pretty sad shape.

Will the 1986 150 fit on the 1977 175 mid? I looked at the gasket part numbers and they are different numbers. Just by looks it looks like the studs are in about the same location and everything else looks similar.

 

[Cogburn]

Re: 1986 150 powerhead fit on 1977 175 midsection?

Anybody know?? Help?

 

[Faztbullet]

Re: 1986 150 powerhead fit on 1977 175 midsection?

Will the 1986 150 fit on the 1977 175 mid?

It will fit if you change adapter plate also. The 2.0L 175 of the early years had a "D" shaped exhaust on the block and plate and the newer 2/0L are rectangular. Below is 175 gasket so you can see difference and wiring harnesses are different also.

 

[Cogburn]

Re: 1986 150 powerhead fit on 1977 175 midsection?

Cool!

So basically use the adapter plate for the 150 and get the appropriate gaskets for that.
I have a seloc manual that should have the wiring diagrams for both. I just put in a new stator, trigger, and power packs on the 175. All that stuff should also work on the 150.

 

[Cogburn]

Re: 1986 150 powerhead fit on 1977 175 midsection?

Well, we did the big switch today and it went pretty well.

Thanks for the help!!

We ended up using most of the 150 except for the lower unit, swivel and tilt. the mid gaskets are the same but the lower exhaust is a little different as is the adapter. So we used the 150 powerhead , adapter, mid , controls and the 175's lower unit, swivel bracket and tilt&trim unit, and cables.

Kind of an interesting project. The 150 had some bad wiring for the tilt switches and a bad switchbox. Also, whoever did the link and sync had no idea what they were doing. It is always easy to see that because the screws are all adjusted past where the original painted area was on the screws(maybe they forgot to unhook the idle stabilizer first?).

Anyway it now has oil injection which seems to be working. Is the Mercury system pretty good?

We also switched controls and wired the tilt & trim to the boat mounted tilt unit.