Evinrude 7.5 idle

[james hobson]

My 7.5 does not want to idle I cleaned carb and rebuilt new points coils condenser still won’t idle 1956 evinrude ; any tips

[crosbyman]

idling requires fuel delivery from the low speed side of the carb did you try adjusting the LS needle

are you using a pressure tank or a converted to fuel pump set up ??

cleaning the complete low speed fuel route involves pullling the top dime size cap and cleaning the low speed drip chamber did you do that ?

is this a new /recent issue with the motor ? how is compression ?

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[fleetwin]

Well, the possibilities are endless….
So, always start with the basics like compression. Have you checked spark, replaced the plugs? Are you sure the engine is running on both cylinders? Does the engine run properly at high speeds? Does it sneeze and cough at idle, or just run crappy and stall? Anyway of posting a video of the engine misbehaving at low speeds? When was the last time it ran properly?

[reivertom]

Check the compression. If it is low, it will run faster, but won’t idle worth squat.

[james hobson]

Use I use pressure tank Clean carb clean LS took plug out still idles crappy runs good at high speed .

[james hobson]

Runs crappy and stalls , replaced plugs points condenser rebuilt carb set timing.

[james hobson]

Definitely running on both cylinders; does not spit and cough just lidles crappy and dies

[crosbyman]

well what are the compression numbers ??? if electricals are OK we can assume it is not sucking fuel properly to feed the cylinders

check all negative pressure points…

a- starting at the fuel pick-up (change tank and hose if neeed be )

b – divide to conquer…. feed the carb manually with a small fuel supply and hose to the carb inlet thus bypassing the, air pressure pulse , hoses and pressure tank as a problem source

if idling is ok work backwards . low pressure pulse feeding the tank (bad check valves behind the inlet manifold)

c- if still idling bad with a small fuel supply on the carb inlet …….. problem is on the engine side

d- possible loss of crankcase negative pressure causing a weak pull on the carb idle circuit fuel supply ( crankshaft bearings allowing external to be sucked in the crank case instead of fuel from the carb)

e– carb gasket not sealing , LS needle packing inadequate sealing,

f- check the throttle plate at the rear of the cab .. it should be pretty well closed at idle to have the fuel sucked out of the idle chamber

g- btw did you clean out the VERY small jet in the side fuel channel feeding the upper half of the carb ? (look closely inside the feeder
channel) clean it out with a VERY VERY small wire and flush with carb cleaner and air pressure blast

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• This reply was modified 4 years, 6 months ago by crosbyman.
• This reply was modified 4 years, 6 months ago by crosbyman.

[crosbyman]

see info on bleeder valve and poor idling

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[dave-bernard]

or could it be flooding at idle ?

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