70 hp eveinrude bogs

[Billy O]

I have an 84' 70hp evinrude that idles fine but stalls when put in gear unless done quickly. Once in gear it idles fine until given more throttle. It will bog and you have to double pump throttle to get going and sometimes it will pick up on it's own and go. Once going it runs excellent until you idle down again. When trying to put boat on trailer it stalls unless trailer is totallsunk or you get a running start. Carbs have been removed and totally cleaned and blown out.:facepalm:

 

[oldcatamount]

Re: 70 hp eveinrude bogs

When you cleaned the carbs, did you take them all apart to clean the low speed circuit? Sounds like that may be the problem. Are the plugs fairly new and gapped right?

 

[Billy O]

Re: 70 hp eveinrude bogs

Removed everything that would unscrew. Didn't take out anything that required prying,

 

[Ant-Knee]

Re: 70 hp eveinrude bogs

I am kind of new to marine motors,
But what you say it is doing definetly sounds like it is carb related..
Just my opinion..

Thanks,

Ant...

 

[oldcatamount]

Re: 70 hp eveinrude bogs

To clean the low speed/idle circuit, the welch plugs need to be removed. They are smaller than dime size, aluminum, dome shaped caps, one on each carb. I take mine out by drilling (carefully) a 1/8th inch hole through and then using a small prick punch in the hole, and pry them out. They pop right out easily. Drilling may not be the best way to remove them as it will leave tiny bits of aluminum inside the chamber that absolutey needs to be cleaned out of there. Cleaning the orfices is critical. A good quality carb cleaner and compressed air is the safest way but, I use a piece of fine (soft) wire to poke through the openings. To re-install a new welch plug, place the plug into the opening , use something a bit smaller than the plug as a punch (I use the back end of a nail set) and lightly tap the punch with a mallet. The goal is to slightly indent the dome of the plug and by so doing, tighten it into the opening. Not a hard job at all but, you will need a couple new welch plugs that come with a re-build kit. When re-installing the carbs, be certain the linkage rod between the carbs opens both throttle plates at the exact same time. There's probably no adjustment here anyway, just take a look at stuff like that when putting the carbs back on.

 

[Billy O]

Re: 70 hp eveinrude bogs

Thanks Catamount, I take the apart and let soak a couple of days in carb cleaned the blow high pressure air through every hole I can find. Hate to buy the kits just for those plugs.Know of any workaround for that?

 

[oldcatamount]

Re: 70 hp eveinrude bogs

There really isn't any way to short cut around cleaning the carbs, but soaking them in carb cleaner is probably the nearest thing to it. The chances of finding the correct size welch plugs without buying the right kits, are next to none.

 

[ob]

Re: 70 hp eveinrude bogs

Check to insure the throttle linkage roller/bushing is aligned exactly on center with the scribe line of the throttle cam when engine is in neutral. The roller needs to be aligned and 'just touching' as in not holding the carb flaps cracked open. This setting is very critical and if out of adjustment will show its ugly face when attempting to throttle up from a stop when in water. Also if that 3 cylinder looper is set too low on transom the excessive exhaust back pressure will cause a similar situation. Make sure the anti-ventilation plate is roughly level with the pad of the boat when trimmed level. Check the linkage first though.