hello!newbie!1967 johnson seahorse 20hp starting question

[jay42782]

hello everyone

my name is jason and i just joined the site and also just bought a 18' jon that came with a nice looking but not good running 20hp johnson,lol.i am still not a 100% on the year but close.i was told 66 or 67.the motor is all white with a johnson black decal on both sides and seahorse written on the back

ok....supposedly this motor was gone through last year by a local marine shop including carb rebuild,lower unit seal,tiller handle and got her running good.a few months ago my buddy said he was out in it and it started running rough.he then shut the motor down and it would not start.i can get it to run on only starting fluid.i only ran it for a few seconds just to see what i had to work with.there is a lean rich knob on the front.the part of the knob that threads into the bottom of the carb has been broke off in the carb,so when you try to ajust the knob it only turns at the top.not sure if this has anything to do with it or not?

i have a new pressurized tank,new hose and hand pump from tank to motor.it is getting fuel to the carb but when i pull the plugs it doesnt seem like they are wet?

any suggestions? thank you all!!

 

[david_r]

Re: hello!newbie!1967 johnson seahorse 20hp starting question

dont spray starter fluid in the carb it has no lubricant use a spray bottle with pre-mix if you ahve to prime it that way.

i have a '64 evinrude 18hp and if my tank vent isnt open it doesnt run very long.

check your spark it should jump a 7/16 gap with a good blue spark.

have you ran a compression test?

 

[matt9923]

Re: hello!newbie!1967 johnson seahorse 20hp starting question

motors 66-71 im thinking. sounds like something was in the tank. now your not getting fuel. clean carb and don't touch the needles cause u cant get new ones or for 100$+. maybe rebuild the fuel pump? u said its getting gas but if it only starts on fluid? no fuel and put some oil in the cylinders their running dry on that fluid. It sounds like fuel. maybe has some dirt or water in it.

 

[david_r]

Re: hello!newbie!1967 johnson seahorse 20hp starting question

welcome to iboats jason!

 

[eavega]

Re: hello!newbie!1967 johnson seahorse 20hp starting question

Don't know about a 67, but the 68 20 HP only has a slow speed needle adjust. The high-speed is fixed. When you turn the knob on the front of the motor, it should only be turning the top needle via the metal arm and plastic connector to the top (slow speed) needle.

Second all the folks who say don't run starter fluid of any sort. You do that, you are running without lubrication.

Cover your basics; check compression first on both cylinders. When you are sure that both cylinders have adequate compression, then check spark. Easiest way to do that is with an inline spark checker from your local auto parts store (or a Harbor Freight, if you have one close by).

Next, trouble shoot your fuel path step by step; from the tank, through the line, into the fuel pump, and to the carburetor. If everything is kosher thus far, then you probably need to re-clean your carburetor.

-E

 

[jay42782]

Re: hello!newbie!1967 johnson seahorse 20hp starting question

wow!!! this place is going to be great i can already tell!!thanks for the quik replies.for the mixture knob does the part that threads into the bottom of the carb that broke have any affect on the knob.it still turns the top ok.thanks

 

[jay42782]

Re: hello!newbie!1967 johnson seahorse 20hp starting question

sorry guys.i just asked a question eavega just answered.i will check some basics and get back with ya.thanks again

 

[jay42782]

Re: hello!newbie!1967 johnson seahorse 20hp starting question

hey guys!

well.i got her running tonight! i took the carb apart to find it was clean as a whistle.until i removed the needle.underneath the needle was half full of sludge.so.while we were trouble shooting this a friend took the plastic catch off the rich lean knob and turned it way out of whack.could someone tell me where ballpark is just to get it close so i can then fine tune?other than that she runs great!! thanks again all!!

 

[55'Fleetwin7.5]

Re: hello!newbie!1967 johnson seahorse 20hp starting question

hey guys!

well.i got her running tonight! i took the carb apart to find it was clean as a whistle.until i removed the needle.underneath the needle was half full of sludge.so.while we were trouble shooting this a friend took the plastic catch off the rich lean knob and turned it way out of whack.could someone tell me where ballpark is just to get it close so i can then fine tune?other than that she runs great!! thanks again all!!

When in doubt... very very gently seat the needle and then back out one full turn...

 

[eavega]

Re: hello!newbie!1967 johnson seahorse 20hp starting question

From the FAQ section, Carb needle adjustments by Joe Reeves

http://forums.iboats.com/showthread.php?t=167352

Great to hear you got it running. I put mine (1968) on the lake this weekend, and it pulled my boat with two heavy guys plus fishing gear quite well.

-Eric

 

[jay42782]

Re: hello!newbie!1967 johnson seahorse 20hp starting question

great!! thanks guys,cant wait till tomorrow to fine tune this machine.sorry for asking this question but when you say turn the needle all the way in then back out 1 or 1 1/2 turns your reffering to turn clockwise in then out counter clockwise/ thank you!

 

[matt9923]

Re: hello!newbie!1967 johnson seahorse 20hp starting question

great!! thanks guys,cant wait till tomorrow to fine tune this machine.sorry for asking this question but when you say turn the needle all the way in then back out 1 or 1 1/2 turns your reffering to turn clockwise in then out counter clockwise/ thank you!

Yes clockwise in very gently till it stops to hard and you could damage the needle and you cant get new ones or for 100+ if u can find them. then out (counter clockwise)
Matt Good luck i just had to buy a new used carb off eBay cause of damaged needles.

 

[jay42782]

Re: hello!newbie!1967 johnson seahorse 20hp starting question

Yes clockwise in very gently till it stops to hard and you could damage the needle and you cant get new ones or for 100+ if u can find them. then out (counter clockwise)
Matt Good luck i just had to buy a new used carb off eBay cause of damaged needles.

ouchhhh.......sorry to hear that.thanks alot for your help as well as others.i will post how she turned out tomorrow.thanks again!!

 

[eavega]

Re: hello!newbie!1967 johnson seahorse 20hp starting question

you cant get new ones or for 100+ if u can find them.

That's the second time I have found someone saying these needles are hard to find. On the '68, The online catalogs still show the slow speed needle as available for $25. I got slow speed and high speed needles for a 1960 10 HP Johnson I used to own for about $25 apiece. For my '68, I got an entire NOS carburetor for less than $100. Are they really that hard to find, and have I just gotten lucky?

-Eric

 

[matt9923]

Re: hello!newbie!1967 johnson seahorse 20hp starting question

That's the second time I have found someone saying these needles are hard to find. On the '68, The online catalogs still show the slow speed needle as available for $25. I got slow speed and high speed needles for a 1960 10 HP Johnson I used to own for about $25 apiece. For my '68, I got an entire NOS carburetor for less than $100. Are they really that hard to find, and have I just gotten lucky?

-Eric

i have a 1970 or 71 Johnson 33hp. I just found out they year may be older but i don't know the guy before wasn't smart on boats. Anyway for my model all their was was the high speed for 38.95 and i needed bushings, packing and needles. Over 100 from the only site i found anything on. i know other models would fit i just bough a 1959 35hp carb that's in good condition i just cleaned it tonight from ebay for 60$. Will put it on tomorrow and hope for the best.
what do the leaf valves do? why do they have them?
Good luck Matt

 

[jay42782]

Re: hello!newbie!1967 johnson seahorse 20hp starting question

hey guys!

i got home from work today and got the old johnson running really well!.seems that it runs the best about 1 turn maybe 1 1/8.i think i have everything under control thanks to you guys but there is maybe a couple more small things?

1.after getting it running... runs great but smokes alittle (probably common)but sitting there next to it while running smooth the smoke will burn your eyes pretty good.not sure if maybe i need to play with the mix knob some more or not?

2.i replaced the in and out fuel lines today due to a slight hole in one.there were no inline fuel filters on there and didnt no if it would be a good idea to get a couple for both lines?

thanks again fellas!

 

[eavega]

Re: hello!newbie!1967 johnson seahorse 20hp starting question

1.after getting it running... runs great but smokes alittle (probably common)but sitting there next to it while running smooth the smoke will burn your eyes pretty good.not sure if maybe i need to play with the mix knob some more or not?

May smoke quite a bit if there was krud in the cylinders. Also, its a two stroke motor, it burns oil as it runs, so its gonna smoke. From what I have read using synthetic two stroke oil instead of conventional two stroke oil will reduce the smoking some. Also, keep in mind if you were running it in a barrel the smoke is gonna just kind of hang out. When you are on the water, you may leave a fog trail behind you, but it ain't gonna be in your eyes

2.i replaced the in and out fuel lines today due to a slight hole in one.there were no inline fuel filters on there and didnt no if it would be a good idea to get a couple for both lines?

The fuel pump has a fuel filter built into it. Its just a metal screen, so I don't know if its gonna filter out all that much. If you really feel the need for a filter, put one inline from your fuel tank.

-Eric

 

[jay42782]

Re: hello!newbie!1967 johnson seahorse 20hp starting question

thanks eric! i'm gonna take it out on the water soon and see how it does.thanks again