78 erude v4 140hp lower unit interchange?

xikxak

Petty Officer 1st Class
Joined
Sep 16, 2004
Messages
318
can I replace my manual shift lower with a 77? hydromechanical shift unit? are shift patterns same.everything else matches up(except shift rod which I can take care of.mainly shift pattern. Thanks much.
 

Dhadley

Supreme Mariner
Joined
Feb 4, 2001
Messages
16,978
Re: 78 erude v4 140hp lower unit interchange?

If I read this right you have a 1978 140. You want to know which lowers will bolt up. Since you didnt say, we'll assume you have a 20" motor.<br /><br />A 1977 140 unit will work. Not a 1977 or older 85 or 115. Not a 1976 or older 135. Any 1978 and newer V4 unit will bolt up. A V6 gearcase will bolt up but you'll have a wierd gear ratio to power combo. A V8 case will bolt up but that gets really wierd...<br /><br />Dont worry about cutting / welding / modifying the shift rod. Its lots easier to simply use the shift linkage (mounted to the block) that matches the gearcase.<br /><br />Good luck!
 

xikxak

Petty Officer 1st Class
Joined
Sep 16, 2004
Messages
318
Re: 78 erude v4 140hp lower unit interchange?

Dhadley, it will bolt up ok,my concern is the difference if any in shift pattern of the hydromechanical unit that will not match my shift controls for straight mechanical unit.is there any difference besides just having an assist cylinder. thanks
 

Dhadley

Supreme Mariner
Joined
Feb 4, 2001
Messages
16,978
Re: 78 erude v4 140hp lower unit interchange?

I think youre asking if it will shift backwards from one to the other. Yes I believe they do but it doesnt matter. <br /><br />If youre going to use a 1977 140 lower, just use the linkage from the powerhead of the 1977. Besides if you try to modify the shift shaft, you wont know what to set the shift rod height at.<br /><br />Remember, the lower from a 1977 85 or 115 wont work.
 

xikxak

Petty Officer 1st Class
Joined
Sep 16, 2004
Messages
318
Re: 78 erude v4 140hp lower unit interchange?

I don't have the linkage from the 77.Maybe stupid question here,what if I turn my throttle shift control on my consol around.single lever control.
 

xikxak

Petty Officer 1st Class
Joined
Sep 16, 2004
Messages
318
Re: 78 erude v4 140hp lower unit interchange?

bump
 

xikxak

Petty Officer 1st Class
Joined
Sep 16, 2004
Messages
318
Re: 78 erude v4 140hp lower unit interchange?

Can anyone answer my stupid question? Turn around controls. Thanks
 

xikxak

Petty Officer 1st Class
Joined
Sep 16, 2004
Messages
318
Re: 78 erude v4 140hp lower unit interchange?

Dhadley,I dont have the linkage from the 77,will it work if I turn my controls around?I think it will shift but will I get full throttle? Yhanks ,anyone?
 

Dhadley

Supreme Mariner
Joined
Feb 4, 2001
Messages
16,978
Re: 78 erude v4 140hp lower unit interchange?

Probably not. Without knowing what control you really have its difficult to give an answer. But generally speaking, there isnt as much throttle travel in reverse as forward.<br /><br />If you have a control that the cable can be reversed fron a "pull for forward" to a "push for forward" (and vise versa) then it would work. The OMC controls generally arent like that. Some Morse or some Teleflex controls are.
 

xikxak

Petty Officer 1st Class
Joined
Sep 16, 2004
Messages
318
Re: 78 erude v4 140hp lower unit interchange?

Thanks much,I just might get another lower unit,straight mechanical.
 
Top