Logo
FULL SITE MENU

1964 9-1/2HP Seahorse Issue

C

Choppa

New member
Newbie here! Installed a new fuel pump, rebuilt the carb, & changed out all the fuel lines all the way back to the tank. Two newest problems are: I can't seem to get it started w/o use of a small shot of ether. Once I do that she immediately fires on first pull and runs like a swiss watch. If you shut it down, you'd pull you brains out trying to get it re-started without any luck. Give it that shot and she comes to life. Primer ball seems to be hard but not as hard as I feel it should be. I do see a little bit of a weep at the fuel tank quick disconnect fitting which I replaced. Weep seems to be from wear of the fitting tank side. Second problem is poor running or running at all when engine cover is put back on. Pull the cover away and it smooth's right out and run perfectly. BTW What is the fuel mix of this motor 50:1 or 25:1?

Thanks for the replies and great job with the forum!
 
Just ran out checked the exhaust hose. Little loose but not loose enough to fall off. Looks like I can get a hose clamp on it so I'll try that first. Air holes are clear and clean. For the slow speed knob/screw I have: Bottom screw slightly, back out 1-1/2 turns, start engine, turn in 1/8 turns, allow engine to adjust, and continue to turn in until engine dies. Upon which back out screw by 1/4 turn. Note idle may need to be adjusted down during procedure. Does this sound Correct, y/n? Thanks for responding
 
Removed exhaust hose. Plugged the ends with thumb and finger slight tug and hose folds in on itself. Indicating no holes in hose. Replaced factory spring clamp with hose clamp & reassembled. Nice and tight now. If I can get the low speed screw adjustment procedure, will do and head to the pond to see how she runs. Thanks
 
Time to do a spark test on this motor.------------Will spark jump a gap of 1/4" or better?----------Has the motor had a kit installed to deal with the motor shaking too much at idle speed ?-------Look for a bracket from carburetor to lower cowling and the exhaust manifold to lower cowling.
 
I have more spark than I could ask for. Just got done running the river. She ran good today! I dont seem to have an issues with any type of shake. Still think one of the problems stems from seeing a little bit of a weep from the fitting at the tank. I took the plugs out after the return trip, burning very well, Very surprised no one has answered the question of how to adjust the low speed screw. Im convinced it's a fuel delivery problem. Im sure the tank fitting is something that is nolonger available.
 
The 9.5 HP in 1964 came equipped with a fixed high speed jet.------Someone may have installed an accessory adjustable high speed kit.
 
no such thing, high speed orifice is fixed. It must be pefectly clean, and not beat up from wires or tools. Slow speed knob setting procedure is snug it up then back it up 1 1/2 turns, this is a rough tune, and it should start in this position. After that find the sweet spot that lets it idle down low smoothly. Wait 20-30 seconds after each 1/4 turn to really give the adjustment time to take effect. Note that if the low speed knob doesn't seem to change anything, the carb (idle passage way) is not clean enough, back into the solvent! Good luck! I love my 9.5, and will continue to share lessons learned with the board.
 
Thanks..& agreed on two counts: the high speed jet is fixed & I love this motor also. Too bad the 9-1/2's seem to get a bad rap. I am at the 1-1/2 turns out now. Anyway, todays updates: Decided it was time for a new gas tank. Old one rusty and I couldn't get it to stop the leak right at the fitting. Done one problem fixed. Gave it a quick driveway rip to see if it helped the cold start problem. Prime, pull your brains out, stop, give it one tenth of a second ether shot & half way thru the pull she's running smooth as silk. Oddly enough I was talking to some of the marina folks they mentioned they have a guy who's been starting his 40+ yr old motor the same way for years and it works. Not sure I agree but who knows... They also said may not be a bad idea to do a compression check. I'll lick this problem sooner or later along with the help of this forum. If work cooperates I'm headed to the pond later in the week to tweak the slow speed knob, I can't be too far off cause pulling the plugs they look beautiful. I'll post my results. Thanks again all!
 
Starting spray isn't terrible as long as its got a little oil in it to prevent the motor from running dry. Ultimately there is something wrong though if it will not start without it. Maybe run a tank with seafoam through it to see if it will clean the carb sufficiently. Compression should read about 60ish, and similar in both.
 
The other part I will need to look for is Johnson p/n 379162 called out as Rack + Link. This would be the shaft which connects the ring gear end of the tiller to inside the case for the throttle linkage. I am told a common wear item unfortunately hard to get these days. Thanks!
 
Part # has been superceded to the 68 # and it is in stock on this site.------If you could walk over I have a bunch at less money.
 
Compression check completed. 75-77 psi equally in both cylinders. I assume that is fairly decent for a "64" New fuel tank is working well and with really fresh gas/oil she smells & smokes of the ol'two stroke I know. Had some spare time the other night and played with the low speed jet setting. Not much if any change on how it ran. Therefore may consider taking carb apart again and resoaking as andrew04 suggested. Worse part is fall is here and the end of the season is coming quickly.
Will be ordering up the rack piece shortly so thanks for the P/N
 
Back
Top