recirculation hoses misrouted

[guy74]

I've been chasing problems on a poorly mantained 1989 100XP Evinrude. Got the carb problems straitened out, but it stumbles around 2000rpms. It has stumbled with two diferent sets of carbs, both sets of carbs have been meticulously cleaned and rebuilt. We took the boat out this eve, it ran great exept for the stumble around 2000rpm. I was just checking my factory manual for ideas as to why it doesn't run right. I noticed that the recirculation hoses may not be routed correctly. Could the recirculation hoses being misrouted cause it to stumble? I'm gonna change them around to the correct routing, but wonder if this is the cause of my stumble. I'll find out next time I go to the lake, but I'd like to here from anyone who has any experience with this type of thing.
They are supposed to be routed:
#1 & #2 to center main bearing
#3 to #1 bypass cover
#4 to #2 bypass cover
Mine are routed:
#1 & #2 to #1 bypass cover
#3 to #2 bypass cover
#4 to center main bearing
I wish I would've check this alittle closer when I had the carbs off last time, it would've been easier to fix with the carbs off. I guess thats what I get for thinking that it was right.

 

[Dhadley]

Re: recirculation hoses misrouted

That may or may not be the problem at hand but you should route them correctly. You don't want any of the hoses from any cylinder going back to it's own.

 

[guy74]

Re: recirculation hoses misrouted

Thanks for the reply, Dhadley. When I accelerate it acts like something is upsetting the air fuel mix, it doesn't idle as well as I'd like, and it acts like it drops a cylinder or two as I pust the throttle forward. But it comes to life after about 2200 rpms and runs out good. I'm not sure if the recirculation hoses being misrouted could cause this, but it cant help. Last time out my carbs were flooding alittle, and it didn't seem to stumble on acceleration, so the recirculation problem might be allowing it to lean out at that rpm. I'm not sure of the theory on how the recirculation system works, so I have to guess at what it can cause.

 

[guy74]

Re: recirculation hoses misrouted

I got them all routed to the correct places, hope to give it a test this eve. I was able to use a long pair of needle-nose pliers to reach the fittings without removing the carbs.