1968 sportwin 9.5 manual choke

[Haut Medoc]

Hi All.....
I use this for a kicker.....
It ran fine a month ago. but when I went to start it today, it started, but quit immediately when the choke was shut off.....
This engine always purred & was a one pull starter.....
So.....I pulled off the cover & began to investigate....
The throttle plate was stuck & I was able to get it to loosen with some Kroil & gentle pressure back & forth until the spring does what it is supposed to do (close it)...
So I figured, "problem solved"....Wrong!.....
It will stay running if I pump the bulb, so I guess it needs a rebuild on the pump. this is a type III carb that the Sealoc manual (I know!) says can be rebuilt....
I'm pretty sure I can handle that, but I also want to make sure that I haven't hurt anything with regard to the linkage.....
The is a pin that rides along the eccentric plate that revolves when the throttle is turned & pushes the plastic thingy on the throttle plate rod.....
It seems to me that when at full throttle,the throttle plate should be at 90 degrees, not 45 or so....
I could be wrong, but I'd like to see a pic of that linkage to be to be sure....
Anyway, before I tear into it does anyone have any useful input?....
It does not seem like a carb issue, but again, it does not want to stay running with the choke open...
Most of the posts on the subject have dead links, so any new info would be appreciated.....Thanks!

 

[F_R]

Are you sure the throttle control is going to wide open? It won't unless it is in forward gear.
Sounds like the high speed jet is plugged. It is deep in the hole behind the hex drain plug in the very bottom of the carburetor. It must be absolutely CLEAN. But don't be jamming wires and drills and stuff through it. That is a precision hole.

 

[F_R]

Carburetor throttle plate must just barely be ready to start opening when cam follower is aligned with mark on cam.

http://s19.postimg.org/qfdn2en77/9_5hp_throttle_sync.jpg

 

[Haut Medoc]

Thanks, that's a good start.....
I know I was not in gear while checking that, so I will do that in the PM tomorrow....
What would you suggest to clean the passage with?....
I have to say that the filter, etc. looked very clean.....
Is there an easy check to see if the pump is bad?...
Thanks for your help!....

 

[F_R]

It's best to remove the jet for cleaning, but it requires a special screwdriver. But it can be cleaned in place after the carburetor is taken apart. Use commercial carburetor cleaner (dip type best).

Don't worry about the fuel pump yet. You should be able to start and run the motor a short time just on the fuel you put in the carburetor with the primer bulb. THEN the fuel pump takes over to keep it running. If you can keep it running by continuing to squeeze the bulb, then you may suspect the fuel pump....after checking for air leaks in the hose & tank. Just use common sense and think about it.

 

[Haut Medoc]

OK.....
I checked the cam follower & it & the throttle plate do work as it is outlined in the diagram you provided......
The engine will run & continue running (roughly) with the choke on, but will quit if the choke is opened, so I'm thinking it is not the fuel pump....
In the past, it would only need choke when it was dead cold & would quit if the choke was left on too long....
Do I need to remove the carb completely to get to the jet?
Will I need to disassemble it the entire carb or can I just remove the jet?.....
What does the special screwdriver look like?....
Thanks again for all of your help!....

 

[F_R]

Blade sides are ground parallel. Ordinary tapered blade tends to spread the soft brass jet, making it tighter in the threads and harder to get out. Also, round stock all the way to the tip avoids buggering up the threads in the carburetor.
http://s19.postimg.org/5dmufjwmr/fixed_jet_screwdriver_tip.jpg

 

[Haut Medoc]

Where did you get that, does it have a special name?...
I can certainly see the benefit....

 

[Haut Medoc]

UPDATE: I had to remove the carb to get at the high speed jet, really not to difficult at all.....
I was able to get a rebuild kit for the gaskets I needed locally, ( I live pretty close to Seaway in Seattle).....
The carb looked pretty clean, but I completely disassembled it & boiled the parts in a special parts washer a guy at work has...
The aperture on the high speed jet had a small bit of residue & I ran some sized wire from a kit I borrowed until it wouldn't pass though.....
It now is running like it should.....
Thanks F_R!.....
P.S. I was able to fashion a screwdriver like the picture you provided by cutting the head off a nut driver that was the correct diameter & the cutting the end until I got the proper thickness of the groove....
A little filing & emery cloth & it was a good fit....
My thanks again for the screwdriver info, I can see how the wrong one could really "screw up" the jet & threads in the body!....

 

[F_R]

Thanks for the report. It is good when somebody confirms what we have said.