Hard Starting Classic 40 hp

[beatlebob]

"Hello friends, My 1995 class

"Hello friends, My 1995 classic merc 40hp 4cyl runs like a dream once it warms up but drives me crazy just getting it to idle and warm up. I know that it has a fuel enrichment system instead of a choke for cold starts. If I hold the key in does it continously pump gas into the carbs or is it just one shot at a time regardless of how long you push the key in...Also i have to adjust the lean mixture on the carbs to about 4 1/2 turns out to get it running smoothly. Book says that it should initially be adjusted 1 1/2 turns out. Acts like it is starving for gas when cold but idles like a baby when warmed up...is there any way to change this to a manual type choke..Thanks in advance for any advice shipmates....."

 

[galamb]

"The enrichment system can cau

"The enrichment system can cause a hard cold start but if have to richen it that much to get it to run you probably have a clog (or at least some varnish) in the low speed jets of at least one of the carbs - so you could have two separate issues here.

There is kinda two stages to the enrichment system on your model.

If you turn the key to RUN and hold in the key the enrichment valve opens, and gravity feeds (continuous flow) some gas from the top carb bowl to the lower carb intake (but only "primes" the lower carb).

If you then turn the key to START and keep it pressed in it then also allows extra gas to be drawn in through both carbs.

Are you doing the two stage "prime", keeping the key depressed first for about 5 seconds before you try and start, then holding it in during a start to also prime the top carb?

If not, give that a try before doing further troubleshooting.."