no forward or reverse at full throttle

sconger77

Cadet
Joined
Sep 21, 2015
Messages
7
First time having boat on water and at full throttle have no reverse or forward. Bought boat used so no idea what problem could be it is a 1978 imp Navajo ii with electric shift. It has 302 v8 190hp engine
 

southkogs

Moderator
Staff member
Joined
Jul 7, 2010
Messages
15,034
Welcome aboard sconger:

Are you certain it's electric shift? '78 should be hydro-mechanical.

If it's electric shift, you probably want to start by testing the voltage to the shift wires. Wires are on the port side of the engine, running into the intermediate housing. disconnect those wires, do not start the engine but turn the key on. Push the throttle into the forward position and test the forward wire for 12v. Pull the throttle back and test the reverse wire.
 

sconger77

Cadet
Joined
Sep 21, 2015
Messages
7
no I'm not sure its electric shift model # 981061 on plate on upper unit. Thanks, I will look at wires this evening and let you know what I find.
 

southkogs

Moderator
Staff member
Joined
Jul 7, 2010
Messages
15,034
I have a feeling the number you've posted is the part number for the upper gear case. When you go into your engine bay, look for a tag on the engine somewhere (mine is on the rear engine mount on the starboard side). Those tags are the identity of the engine & drive.

BUT ... they do get mixed and matched sometimes. Shoot a photo of your drive and post it here (you'll need to make one more post before it'll work for ya').
 

sconger77

Cadet
Joined
Sep 21, 2015
Messages
7
I also tested wires that lead to drive and got no power to them. I took apart throttle and there is a switch in there could this be bad causing no power to drive
 

southkogs

Moderator
Staff member
Joined
Jul 7, 2010
Messages
15,034
That's electric shift ... Intermediate looks a little newer though, so you may have a couple mix/matched pieces: but that shouldn't matter too much.

Look for that tag on the engine: '77 was the last year for the electric shift 190HP, and the numbers would read something like 990232GST.

As regards the shifting, start with the 12v test above.
 

bruceb58

Supreme Mariner
Joined
Mar 5, 2006
Messages
30,610
Just so you know, you don't test voltage across those 2 wires. One wire is for reverse and one wire is for forward. They are never activated at the same time. You need to measure each wire in reference to ground depending on where your console shifter is. Your ignition needs to be in the on position when you do the test.

EDIT: I see Southkogs already mentioned this in post $2.
 
Last edited:

bruceb58

Supreme Mariner
Joined
Mar 5, 2006
Messages
30,610
Need to find out if there is voltage to the input of the switch.
 

VE8EV

Petty Officer 2nd Class
Joined
Sep 5, 2012
Messages
109
That shifter looks... odd. Has anyone else ever seen an electric shift switch like that? It almost looks to me like its just a starter interrupt switch in there.
 

southkogs

Moderator
Staff member
Joined
Jul 7, 2010
Messages
15,034
The model number is 990232G
'77 190 - 302 FORD with Selectrim. You can use that number to search for parts. Getcha' a shop manual for it. You'll need it :)

That shifter looks... odd. Has anyone else ever seen an electric shift switch like that? It almost looks to me like its just a starter interrupt switch in there.
Only in pictures, but I have seen 'em like that. Dunno' much bout 'em ... but the switch looks similar to mine.

Bruce has got the next order of business ... and likely knows better how to do it than I do.
 

sconger77

Cadet
Joined
Sep 21, 2015
Messages
7
I have a shop manual and found replacement switch online as I tested old switch and it was bad.
 

bruceb58

Supreme Mariner
Joined
Mar 5, 2006
Messages
30,610
I have heard those switches are hard to find and expensive. Nice that you found one.
 
Top