84' 60hP evinrude Running @ 1/2 rpm

[Crazyju]

I have had my boat about about 10 time this season and it has ran great. Smooth idle. Very easy to start. Last night returning to the dock the motor bogged down to 2500 rpm. I ran it for about 10 minutes like this back to the dock. I cut the motor a few times and still would not run past 2500 rpms. Checked the compression this morning 120 on both. Tried it this morning and same thing. Starts quickly, smooth idle. Sound real good just wont go past 2500 rpms. Ive checked the manual and I do not see that this motor has the SLOW feature. I pulled each plug last night and it would run on each cylinder independately. The carbs were rebuilt prior to the season. I am going to check spark tonight. Any other things to check?

Thanks

Carl

 

[jbjennings]

Re: 84' 60hP evinrude Running @ 1/2 rpm

Usually a problem like this is spark but the running on both cylinders independently puts a kink in that theory.
Next, is the motor staying nice and cool? Checked head temp when it starts doing this?
Last of all, you might try getting a helper to restrict air flow to each carb when it's bogging and see if it has any effect on either carb to see if you're not getting enough fuel to one or both of your carbs. Also, see if your tank is venting and make sure your fuel line is good. THose atwood fuel lines/primers are notorious for getting sticky check valves and such.
Good luck,
JBJ

 

[Crazyju]

Re: 84' 60hP evinrude Running @ 1/2 rpm

Thanks JBJ. The entire fuel system is brand new. I bought the omc primer bulb. Gas tank is new 55 gallon will full size vent. Bulb stays hard, and squeezing it while running has no effect. I have a head temp sensor on the top head and it hasnt topped 140 in the 10 trips. But this did occur this morning before it even had time to warm up. Hopefully the spark test will show something this afternoon. Thanks again.

 

[Crazyju]

Re: 84' 60hP evinrude Running @ 1/2 rpm

Well, spark checked out on both cylinders. So on to the fuel system. I ran it up to 2500 rpm, held in the choke and it jumped up to 5500. Top carb not getting fuel. I choked it a few times and it reved up. I think this blew out some blockage. It ran great the rest of the day. Any concerns going forward with this?

Thanks

Carl

 

[seakingbob]

Re: 84' 60hP evinrude Running @ 1/2 rpm

Sounds like the carbs,Did you rebuild them ?If not i think that you should

 

[tashasdaddy]

Re: 84' 60hP evinrude Running @ 1/2 rpm

you could have good spark this morning. but after the motor warms, a coil or power pack, could be getting hot and failing. if it does it in the water again, check spark immediately, right there.

"Any concerns going forward with this? " yeah!! if top is not getting fuel, it is not getting lubrication. only reason i can think of, for it not getting fuel, is the float needle is sticking. thus clean them and make sure. a carb can be clean this morning, and something gets into it. and it ain't clean anymore.

 

[Crazyju]

Re: 84' 60hP evinrude Running @ 1/2 rpm

Carbs were rebuilt at a shop. They ran great for about 10 trips. Then it just cut to half power (one carb no fuel). I ran it for an hour last night after i choked it while running at full throttle and its seems to have blown out the blockage. Fires right up, Smooth idle and back to running like it did. I have a fuel filter on but i guess something still got through.