1969 Johnson Outboard


Old 05-29-01, 11:52 AM
Visiting Guest
Posts: n/a
I have a 1969 Johnson 100 HP outboard engine on a 74 Glastron boat. The motor has been rebuilt both top and bottom I took it to a mechanic who charged me $150 to put a new water impeler in the lower unit and he told me it looked like the lower unit was in good shape, this was about two years ago. I have not had it in the water since and have a question about where and how much water should I see coming out when I use a 50gal. drum to run and tune up the motor. I see the large hole in the center above the lower unit but it appears as though very little water comes out, more like air and vapor. Is this the right place to look at or do I need to look elsewhere? also, why is it so difficult to start, it seems if I pour a little fuel directly into the carb (very large carb) it starts right up, but when I have to prime it and start it , it doesn't want to start. This is an electric start motor. Any suggestions you might have will greatly be appreciated...
Sponsored Links
Old 06-01-01, 07:34 PM
BoatMech's Avatar
Join Date: Dec 1999
Location: Los angeles
Posts: 592
First, dont pour fuel in the intake.
pump the primer bulb and crank it with the choke on.
if it wont start it may be a carb problem.
More likely it is a spark issue.
the magneto on that model is very sensitive.
the hole in the exhaust housing is a relief hole
and most of the water is going down in the bucket.
dont expect too much from the hole.
Try running on the factory style flusher
to see the water flow.
Old 06-06-01, 10:42 AM
Visiting Guest
Posts: n/a
Thanks for responding. What is the bucket? and what is a factory style flusher? I'm a fair mechanic when it comes to cars but outboards are a little different. I'm also having some problems when it does start, it seems to be going very slow, almost like it's only running on two cylinders. Any suggestions on how to verify? Can I just pull the spark plugs while running like a car?
Old 06-06-01, 09:33 PM
BoatMech's Avatar
Join Date: Dec 1999
Location: Los angeles
Posts: 592
When running it in the bucket (55 gal drum)
the cooling water is going down the exhaust and back into
the container.
You can pull the plug wires while running without causing
any ignition damage. I would suggest a spark checker set with a 1/2" air gap.
The flusher attaches to the water intake and connects to the garden hose. You can see the water flow that way.
The sluggishness is probably fouled plugs. How old is the fuel?
Old 06-11-01, 08:28 AM
Visiting Guest
Posts: n/a
1969 Johnson outboard

I'll use some new fuel mix and check the plugs. I'll get back to you on this one. Thanks for your help

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

Thread Tools
Search this Thread
Display Modes