6hp Seahorse

[440racer]

I picked up a 6 hp seahorse from my friend that was store with stabil in the fuel. I installed a tune up kit (ignition) & plugs and got it running pretty well.

Problem is it's running a little rich even with fuel at 50:1.

Haven't dissasembled carb yet because it is running.

I've adjusted the lean knob on front to as lean as it will get and after a little while at wot is starts running rich. Should I dissasemble the carb & clean it or is there a air screw I havent found?

Thanks in advance.

 

[crxess]

Re: 6hp Seahorse

Need year model.
Most 6hp only had low speed adjustment with fixed high speed orifice behind bowl drain.

 

[440racer]

Re: 6hp Seahorse

Need year model.
Most 6hp only had low speed adjustment with fixed high speed orifice behind bowl drain.

It's a cd-22m model. I was just about to go look and see what year but I'm not sure.

There's a richness adjustment knob that sticks out of the front cover to adjust tshile running but I didn't know if there was an adjustment on the carb that was a more permanent setting because as lean as the knob will go it's still running rich.

 

[PW2]

Re: 6hp Seahorse

What do you mean when you say it is running "rich"?

What are the symptoms?

As the prior poster suggested, there is no high speed adjustment--it is a fixed jet carb on high speed. the adjustment knob you see is for low speed jet only

 

[440racer]

Re: 6hp Seahorse

What do you mean when you say it is running "rich"?

What are the symptoms?

As the prior poster suggested, there is no high speed adjustment--it is a fixed jet carb on high speed. the adjustment knob you see is for low speed jet only

That's good to know about the low speed because I have a hard time getting it to run well at slow throttle.

When I say rich the plugs were very fouled withg carbon but I was running it 32:1 before I knew the proper ratio. I installed new plugs and new fuel at 50:1. It still smokes ALOT at wot in nuetral and under WOT under load the motor gradually starts to turn slower revs until I put it in nuetral, run it wot a while, burn the build-up off the plugs and it eventually spins back up, then I put it in gear and it runs well for the first minute or so then begins to run rich again. I haven't looked at the new plugs yet but I bet they're pretty black.

I'll be back at the river this weekend and check.

 

[Tim Frank]

Re: 6hp Seahorse

Sounds like you are mixing terminology.
You may be running fuel that is rich in oil...or richer than the 50:1 that is spec'd.
But the carburetor settings refer to lean/rich as a fuel/air ratio.
Richer mixture here means more fuel less air....leaner means less fuel more air.
Choke cuts off air and thus gives the rich mixture needed for cold starting.

There are lots of threads that you can find in here on carb adjustment.

 

[440racer]

Re: 6hp Seahorse

Sounds like you are mixing terminology.
You may be running fuel that is rich in oil...or richer than the 50:1 that is spec'd.
But the carburetor settings refer to lean/rich as a fuel/air ratio.
Richer mixture here means more fuel less air....leaner means less fuel more air.
Choke cuts off air and thus gives the rich mixture needed for cold starting.

There are lots of threads that you can find in here on carb adjustment.

Yes I am mixing terminology. But I think I've got my oil/fuel mixture correct now. put about 13oz oil in a 5 gal tank. I guess the reason I'm thinking it is running fuel rich is because after time at wot it starts to bog down a little and did I understand correctly from above that the mixture knob on the front of the motor is for low speed only?

 

[tx1961whaler]

Re: 6hp Seahorse

Make sure the spark is good and strong. My 6 was pretty well doing as you described (harder to start, smoky, acted rich at top end), and it was the spark, in particular the points were gapped a bit too wide. Cleaned them (even though new) and regapped them carefully, and now it's a smooth one-pull wonder.

 

[440racer]

Re: 6hp Seahorse

It's been a while but my biggest problem was using too cold a plug. Went to the right plug and it runs a lot better but still runs too rich at w.o.t.

I believe it is the richness needle that sticks out the front of the carb. When I run it at w.o.t and plug the small hole in the face of the carb at about the 1:00 position to the main throught of the carb it runs correctly but if I remove my finger it begins to run too rich (at w.o.t.). I removed the richness needle and the tip is not a smooth taper. It looks worn and my guess is that the needle is not fully seating and allowing fuel past even when fully turned clockwise.

Does anyone know if I could have this needle machined to a smooth taper again or where I could find a new one?

Brp & others sell one (part# 0311340) but their model numbers start at 1968 & mine's a 65 I think.

 

[jay_merrill]

Re: 6hp Seahorse

If the needle valve is "notched," instead of being a smooth taper, someone has screwed it into the carburetor too tightly. By forcing it into the valve seat that way, the needle is "crimped" and, therefore, damaged. The correct way to adjust the low speed needle, is to turn it all the way in until it is lightly seated. You them turn it back out 1 & 1/2 turns. That becomes a reference point for further adjustment.

If you can easily see that your needle has been damaged, replace it. I can't say for sure that the part number for the '68 6hp carb is the same as the '65, but it might be. I would find an OMC/BRP dealer and ask them to look it up. You can also contact Seaway Marine, which is the largest OMC, New Old Stock (NOS) parts warehouse in N. America. Regardless of the part number, they would be among the most likely sources for a new one.

www.sea-way.com



???

 

[1946Zephyr]

Re: 6hp Seahorse

You can tell a damaged needle by a pressed look where it's supposed to seat. A needle is supposed to have a perfect and undamaged taper all the way down. jay_merrill is right on with his post. Start with those settings and turn the needle in about 1/8 of a turn and see if it stops running rich.

 

[Tim Frank]

Re: 6hp Seahorse

Would the low speed needle mess up high speed operation?

 

[ezeke]

Re: 6hp Seahorse

The needle for the 1965 model is part #0311340.

 

[440racer]

Re: 6hp Seahorse

Thanks for everyone's help.

The needle was definitely notched and not a smooth taper.

I took the needle to a machine shop close to home and he re-tapered the needle with the same taper.

I'm looking forward to getting back to the water and trying it out. He took off a lot of material and the needle is probably a good bit shorter now. I will cut some more threads into the needle in case the threads bottom out before the needls seats. If that doesn't work I'll order an new one (Thanks, ezeke for the part number and Jay for the link)

 

[1946Zephyr]

Re: 6hp Seahorse

How much did he have to take off?

If you need to add more threads, then it's likely the carb could be damaged inside too.

 

[kbait]

Re: 6hp Seahorse

Have you serviced the points recently? You may have dirty/pitted point surfaces that work just fine- almost..
I wouldn't think that the low speed needle condition would affect wot.. Scrutinize spark and be sure to use correct plugs. A decarb wouldn't hurt either.

 

[1946Zephyr]

Re: 6hp Seahorse

Points set at .020 and use J6C spark plugs in it.

I had an old 5 1/2 Johnson one time that wouldn't throttle up. I found that it had a pair of J4C's in it. I changed it over to an old old pair of J6J's that I found on my work bench and what a difference that made. I know J4C's were commonly recemended in some of the bigger motors, but I still think they're better off with the J6C's instead.

 

[ray 6688]

Re: 6hp Seahorse

Hi
remove carb bowl and turn motor upside down.
Look at float, the float should sit level with the carb body when it is holding the fuel inlet needle closed.
if not slide out hinge pin and bend tab to correct float position.
The mixture needle will only adjust fuel through slow running drilling in carb body,not high speed mixture.
If you have a straight thick blade screwdriver,you can remove orifice plug
(stupid name for jet)from the lower carb body and clean.
This will be tight so don't force it as the jet is brass.
If it wont come out then leave it.
Regards
Ray
PS I have re taperd mixture needles myself with no problems.

 

[ezeke]

Re: 6hp Seahorse

Hi
remove carb bowl and turn motor upside down.
Look at float, the float should sit level with the carb body when it is holding the fuel inlet needle closed.
if not slide out hinge pin and bend tab to correct float position.
The mixture needle will only adjust fuel through slow running drilling in carb body,not high speed mixture.
If you have a straight thick blade screwdriver,you can remove orifice plug
(stupid name for jet)from the lower carb body and clean.
This will be tight so don't force it as the jet is brass.
If it wont come out then leave it.
Regards
Ray
PS I have re taperd mixture needles myself with no problems.

It's not a jet, so they call it an orifice.

 

[ray 6688]

Re: 6hp Seahorse

Hi
When I gave you some advice earlier,I was thinking 4horse.
On the 6 horse you will have to remove the top bolt from the recoil spool holder.
Very carefully pull the complete starter to one side just so far that you
can get a wrench onto the carb holding nut and undo nut.
replace bolt in starter.
Undo nut on other side of carb,slide carb off studs,then follow what I said in previous post.
If the fuel is not at the correct level this will cause motor to run lean/rich.
The JET in the bottom of the bowl has a recess on these models and be full of crud,even though they look clear.
I am surprised the admiral or whatever did not pick up that I had given you
instructions for the 4hp.
Glad I'm not in his navy !
Ray