Honda 7.5 Four Stroke Help Please

65Mustang

Recruit
Joined
Jun 4, 2009
Messages
3
I needed a small trolling motor for my lake boat so a friend of mine from work told me he has a 7.5 HP Honda four stroke that I can use if I can get it going.

It has sat for the past 2 years in his garage and he is just not using it, well I picked it up today and did manage to get it going, changed engine oil, leg oil and 2 new plugs, tweaked the carb and did a general all purpose service to it.

It runs very smooth and quite but the only problem is that there is very little water coming out of the tell-tale unless I rev it up, and reving it up to get a good flow of water defeats the purpose of having the motor for trolling.

I disconnected the lines and blew them out and there does not seem to be any blockage or obstruction, so I am thinking that the impeller is pooched, but I really do not know.

My friend bought the motor 3 years ago as a used motor and only ran it for one year before shelving it, he does not know what year it is but thinks an 81 or 82. I can not find where the impeller is on this motor and do not want to start tearing into it without some more information.

So if anybody has a repair manual for this particular motor and can check a few things for me I would really appreciate it, or if you have a good working knowledge of this kind of motor that you are willing to share that will also be much appreciated.

1981 or 1982 Honda 7.5 HP Four stroke outboard, runs very well but not much water coming out of the tell-tale unless you really rev it up and just a very few dribbles at idle in gear or in neutral.

If you can help me, thank you very much in advance.


I am new to this board and really have no working knowledge of this Honda 7.5 that I now have, so once again I would like to thank you in advance for any help you can give me so I can get this motor working correctly so i can take my grandkids fishing.
 

65Mustang

Recruit
Joined
Jun 4, 2009
Messages
3
Re: Honda 7.5 Four Stroke Help Please

Check your spark plug wires for a date stamp.
http://novigrad.sitesled.com/1673.pdf
Click on the link above for a complete service manual for your motor.
Nick


Thanks for the info Nick, I have ordered a manual and it should be here in about 7 - 10 days.

So for now can anybody tell me where the impeller is located on this motor ?

Also anybody know where the serial number is located on this motor ?

I was thinking that the impeller might be where I separate the two portions of the leg, is this correct ?
 

Larry G

Recruit
Joined
Jun 5, 2009
Messages
3
Re: Honda 7.5 Four Stroke Help Please

Had similar problem with my 1986 BF75. I had sediment build up inside the intake manifold at port to the tell tail. The port comes off the channel inside the manifold at 90 degrees so just sticking sonething straight up didn't work.
 

dan the tuna

Cadet
Joined
Feb 11, 2010
Messages
16
Re: Honda 7.5 Four Stroke Help Please

Any luck finding the impeller? I'm about to buy that same motor today.

Update Monday. I bought the motor for $500 bucks yesterday. Motor runs great, water seems to be flowing fine. I think I got a pretty good deal. Everything is clean and I even have the original owners manual for it.

The only thing I don't have is the "plug" that goes into the electrical output on the motor. Where can I find this part to buy?
 

wrwetzel

Cadet
Joined
Aug 18, 2004
Messages
11
Re: Honda 7.5 Four Stroke Help Please

The impeller is inside a plastic housing on the top of the gear case. You need to remove the gear case from the extension case to access it. And to remove the gear case you first need to remove the shift rod joint at the top of the shift rod (under the engine cover). Count turns as you unscrew it - count the same number of turns as you reassemble it. If you forget, screw it all the way down and then back off 4 1/2 turns. To remove the shift rod joint you may have to remove the rectifier and possibly a little more for convenient access.

There are a number of little details, such as the shift rod joint I mentioned above, that are well covered in the manual that are not obvious, especially if you don't have a lot of experience working on motors.

I STRONGLY recommend you wait until you receive the manual before proceeding.

Bill Wetzel
 
Top