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1962 75HP johnstone outboard

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popbear

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is there anybody that has ever

is there anybody that has ever worked on a 75 hp.johnstone 4 cyl. engine. i have severe gas problems thanks any help would be greatley app. >popbear<
 
hi tom barker. What i mean is.

hi tom barker. What i mean is.Maybe i should give you a short profile on my engine? first my engine sat for a couple of years before i bought it with a 18 ft. boat. I had a mac. do a carb job on it because when i run the engine the gas just poured right through it >8 miles to0 5 imp gal.< i have played with the adjustments and set them exactley as my book has said the engine has lots of power starts good but the gas. you can emagine with the gas being 4.50 a gal i dont use this boat and moter much. If this is helpful pleas tell me > popbear>
 
"(Carburetor Adjustments -

"(Carburetor Adjustments - Older V/4 Downdraft Carb)
(J. Reeves)

NOTE: The early model downdraft carburetors incorporated "Adjustable High Speed Jets". The later model downdraft carburetors used "Fixed High Speed Jets". Follow the below instructions accordingly.

NOTE: If you do not have adjustable high speed jets, ignore those paragraphs pertaining to same...... BUT do make sure that you manually inspect and clean the two brass fixed high speed jets which would be located in back of the two 7/16" slotted hex head bolts in the bottom front portion of the float chamber.

Lift the center High Speed Control lever and turn it so that the point faces forward, resting on the high ridge. This will disengage the lever control gear from the individual high speed jets (slots). Have the slow speed needle valve knobs installed upside down so that they can be turned without encountering any obstruction.

Gently seat each of the High Speed needle valves, then back each one out one (1) turn. Gently seat each of the Slow Speed needle valves, then back each one out one and one half (1-1/2) turns. NOTE... have the jam nut on the s/speed needles snug so that vibration won't have any effect on them, but loose enough so that you can turn them without a great amount of effort.

(High Speed)
With a reliable person at the wheel, and one kneeling in front of the engine, start the engine (yes, it will run lousy with the above initial needle valve settings), put it into forward gear, and apply full throttle. Start with the High Speed adjustment on the left using a screwdriver that properly fits the slot.

(High Speed Adjustments)
At full throttle, with the proper size screwdriver, slowly start turning one of the H/S needles in segments of 1/8 turn, waiting momentarily for the engine to respond, then repeat turning. You will reach a point where the engine will start to die out. At that point, back that needle valve out approximately 1/4 turn. Now, go to the other High Speed needle valve and repeat that procedure. At some point in that 1/4 turn out, you will find the smoothest high speed setting (you can now lower the throttle rpm). That will have both high speed needle valves set correctly, and at that point you can lift that center lever adjustment of that high ridge, keeping it lifted until the point is facing the engine, then lower it into its proper position. (When you turn that lever now, you're adjusting both High Speed needle valves at the same time.)

(Slow Speed Adjustments)
Now, lowering the rpms of course, take the engine out of gear and set the throttle just to where the engine will stay running. Again, in segments of 1/8 turn, slowly start turning in one of the slow speed needle valves, waiting a few seconds between each turning for the engine to respond. As you turn the s/speed needles in, the rpms will increase..... and as it does, lower the rpms to where the engine will just stay running (otherwise the rpms will climb quite high). You will reach a point whereas the engine will either start to die out or it will spit back (sounds like a mild backfire). At that point, back the needle valve out 1/4 turn. Repeat the process with the remaining slow speed needle. Again, at some point in that 1/4 turn out, you will find the smoothest setting. When finished, tighten the jam nut somewhat, then remove and reinstall the s/speed knobs correctly (right side up).

http://stores.ebay.com/Evinrude-Johnson-Outboard-Parts-etc?refid=store"
 
Hi joe thanks for the reply. I

Hi joe thanks for the reply. I have done all that and i beleave correctly but there is pure gass on top of the water when pulled away from the dock the engine stalled when i went to restart it it backfired and just like a bond movie a trail of fire went for about 10 ft behind the boat >very on nerving. what do you think <popbear>
 
You do not say what type of bo

You do not say what type of boat you have. Have you or your mechanic checked the fuel pump diapragm for a pin hole or a leak that would spread gas on the water?????
 
i have prettey well ruled out

i have prettey well ruled out the carb now.ihave checked out the fule pump every thing seemes o.k. it seemes that this is a fuel problem either carb or fuel pump but what about the timeing how does the gas get from the tank into the engine and out through with out being burnt. Ican't seem to under stand this. As it appears I dont know much about these engines.
 
"Remove the hose that leads fr

"Remove the hose that leads from the diaphram side of the fuel pump to the itake manifold. Pump the fuel primer bulb. If any fuel comes out of that side of the fuel pump, the diaphram is cracked/broken/leaking and requires replacing. At the top of this page, see the manual icon and click on it to see if a service manual might be available. If not available, click on contact and ask Andrew directly if he can get you one.

I'll send you info via your email address on how to time the engine. Pay attention to the timing explanation as I believe it includes both the magneto system and the automotive system.

http://stores.ebay.com/Evinrude-Johnson-Outboard-Parts-etc"
 
Hi JOE I FOUND A BOOK THANKS F

Hi JOE I FOUND A BOOK THANKS FOR THE INFO. I HAVE GONE OVER THE whOLE THING. THE TIMING SEEMES TO BE GOOD' THE CARB SEEMES GOOD' AND THE FUEL PUMP DOESN't leak. There is something that i am missing maybe i should start bu buying a new or rebuilt carb or fuelpump or bouth. It is getting cold on cape breton island up here in canada.Things are beginning to freeze up this engine is not safe to opp.this engine in this kind of weather. Thanks for all your help.any further info will be greatly app. < hecbear>
 
"CAPE BRETON is a nice place ,

"CAPE BRETON is a nice place , no wonder Sir Alexander of telephone fame chose to live there later in his life.Now the motor. What sort of boat is it on and what is the overall condition of the motor.Spending money on a new/ rebuilt carburetor may be a waste. What is the compression on the motor?? If you ran for an hour to go 8 miles there may be nothing wrong. Also have you checked the bottom seal on the crankshaft."
 
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