1953 Evinrude 15 hp hard start when cold

[freddyray21]

Compression 90 lower and just over 100 upper, hoping a decarb and run it will even them out. rebuilt carb, cleaned and reset points, new plug wires, good blue spark with lots of crackle, . It is hard to start cold. Once warm it starts first pull at an idle. Once running it runs great does not miss a beat and idles perfect. Cold start procedure is to prime tank (pressure tank known good as it runs fine on other motor) choke, turn the throttle up all the way and pull like hell until it fires. Seems to be not getting gas. Got it started tonight and did a decarb, but have not checked the compression again yet. I am going to put it on a boat tomorrow and run it before I do a new compression test. Any idea?

 

[tashasdaddy]

Re: 1953 Evinrude 15 hp hard start when cold

second set of instructions here: http://forums.iboats.com/showthread.php?t=167352

 

[jbjennings]

Re: 1953 Evinrude 15 hp hard start when cold

Fred,
Could your float be just a little out of adjustment (too low) and not allowing it to let the bowl fill up enough?? Just a guess. Also, have you tried the ol' propane gas technique to check for air leaks around any gaskets on the manifold/carb etc. ?? That's about the only ideas I have. It's got to be lean mixture upon cold startup I would think???
Good luck,
JBJ

 

[freddyray21]

Re: 1953 Evinrude 15 hp hard start when cold

second set of instructions here: http://forums.iboats.com/showthread.php?t=167352

I've done the adjustments and it runs fine so I don't see where this applies, but maybe I am stupid.

 

[tashasdaddy]

Re: 1953 Evinrude 15 hp hard start when cold

just a suggestion, JBJ has a point also.

 

[freddyray21]

update 1953 Evinrude 15 hp hard start when cold

update 1953 Evinrude 15 hp hard start when cold

Seems I received some bad advice on another board and was told to plug a hole in the carb that appears to be the float bowl vent. I unplugged it and at least for now it seems to be starting very well and running even better. We will see as time goes on. Since it is a cold start problem I will have to check it again tomorrow.

 

[wbeaton]

Re: update 1953 Evinrude 15 hp hard start when cold

Re: update 1953 Evinrude 15 hp hard start when cold

That's the atmosperic vent. Without it you get no vacuum or fuel flow. No wonder it was hard to start. You're lucky it ran at all.

I'm still worried about your compression, though. Do the decarb and recheck.

 

[freddyray21]

Re: 1953 Evinrude 15 hp hard start when cold

a decarb brought both up and within 10%. It will idle very smooth and extremely slow. With all the work I did on this motor it will make a good one. Too bad I don't need it, but it was fun fixing it.

 

[wbeaton]

Re: 1953 Evinrude 15 hp hard start when cold

Congratulations. Its always nice to finally get them running right.