Motor idles, but bogs down when you speed up

[topwater junkie]

I have an '76 15hp E-rude that bogs down when I try to give it some gas. We've put new spark plugs in, cleaned out the carb, and have new gas. We played with lean/rich button, but nothing seems to work. I'm using an older gas tank, could that be my problem?

 

[Greg22]

Re: Motor idles, but bogs down when you speed up

Hi Topwater,<br /><br />Try and pump the fuel bulb when it is bogging down.

 

[topwater junkie]

Re: Motor idles, but bogs down when you speed up

Greg 22,<br />We tried that and it didn't change it's attitude. The buld doesn't get really tight and actually feels like it isn't expanding all he way out when I pump it. Any more ideas?<br />Thanks<br />Topwater junkie

 

[Greg22]

Re: Motor idles, but bogs down when you speed up

Check yor fuel lines to make certain that the rubber does not look deteratied. Make certain that all connections are tight. If it is sucking air that is not good. Also, when you cleaned the carb did you tear them all the way down?

 

[topwater junkie]

Re: Motor idles, but bogs down when you speed up

Greg22,<br />how can I tell if it is sucking air. As far as breaking it down we just took it out, cleaned it out with some carb cleaner and put it back in. It had sat for a year and had some varnish in it when we looked inside.<br />Thanks,<br />Topwater

 

[dkondelik]

Re: Motor idles, but bogs down when you speed up

evenin' topwater junkie,<br /><br />is this a new problem? have you ahd the motor for a while?<br /><br />sounds like fuel deliver problem. try to narrow down the problem. <br /><br />does your primer bulb firm-up when you squeeze it a few times?<br /><br />have you ever replaced the gas lines in the motor? they are old and could be deteriorating, clogging the carb with debris and/or collapsing and choking off the fuel flow. <br /><br />can you get your hands on a nother fuel tank? this would help you conclude if the tank is the source of the problem. <br /><br />if the tank checks out ok and all of the gas lines and bulb are good, then, when running, open her up. as you do, squeeze the primer bulb a few times. if the problem goes away then it's probably time for a fuel pump repair or replacement.<br /><br />all else fails? remove and reclean the carb. pay special attention to the small jets, orafices and channels. somthing seems to be preventing fuel flow.<br /><br />let us know what you find.<br /><br />Good Luck

 

[dkondelik]

Re: Motor idles, but bogs down when you speed up

WOW!<br />alot happened while i was typing that.

 

[topwater junkie]

Re: Motor idles, but bogs down when you speed up

Klondike7<br />Thanks for the idea of eliniating the tank and gas lines. Hopefully that might be the source of my problem. It's my dad's motor and has been sitting for a year. It ran like a champ when it was on his boat, but it's giving me some problems right now. Thank God for trolling motors, at least I can still fish.<br />Topwater

 

[Boatist]

Re: Motor idles, but bogs down when you speed up

Topwater<br />You say moved to another boat. Quick question, Is boat on now a lot heavier boat. What type prop do you have on it. I have seen problem you describe caused by a prop with way too much pitch.

 

[Clutch87]

Re: Motor idles, but bogs down when you speed up

hey topwater <br /> I had the same problems with an old outboard 110hp Merc. and found the water pump was bad, would get the engine hot and would bog every time you give it gas. Just an idea, might not be the same problem, but a place to start.

 

[topwater junkie]

Re: Motor idles, but bogs down when you speed up

Here's an update. I can start the motor and put it into gear, but to give it gas I have to pull the choke out half way. Anyone have any ideas of what I may be looking at now?<br />Topwater

 

[wheelee]

Re: Motor idles, but bogs down when you speed up

Hey Topwater, I had the same problem with my 75 Johnson this spring, I tried all of the above solutions, Ended up finding that the problem was varnish plugging my high speed jets.I changed my needle and seats and high speed jets and problem solved. Hopes this helps!<br /> MW

 

[wheelee]

Re: Motor idles, but bogs down when you speed up

Hey Topwater, I had the same problem with my 75 Johnson this spring, I tried all of the above solutions, Ended up finding that the problem was varnish plugging my high speed jets.I changed my needle and seats and high speed jets and problem solved. Hopes this helps!<br /> MW

 

[bigjohnson774]

Re: Motor idles, but bogs down when you speed up

Rebuild the carbs.....you will be amazed by the difference new parts make. Just did mine.

 

[harleyg]

Re: Motor idles, but bogs down when you speed up

Hi, <br />Can't help but to be sympathetic. I had a similar problem that I played with for 3 weeks. It was a 70hp 3 cyl Johnson. Turned out to be a piece of silicone (like caulking) stuck in a main jet in one of the carbs. In my case the 3 cyl ran well enough to idle and troll on 2 cyl, but bogged out when it was throttled up. It was a hard thing to find as the silicone was stuck and was clear so it was hard to see. Yours sounds like a fuel problem to me, so I wouldn't waste time on changing props, gas tanks, primer bulbs etc. unless they are obviously not working. I did this and just spent money and time for nothing<br />I suggest you try following.<br />1. Check compression on cylinders If all OK then,<br />2. Idle in bucket or with earmuffs and pull spark plug wires one at a time. If one cylinder makes no difference then,<br />3. Check spark plug on bad cylinder, if ok then<br />4. Move a spark coil from one of the good cylinders to the bad one if it makes it work then it was the spark coil, get a new one, if no difference then it is a fuel problem from the carb on that one cylinder<br />5. Take carb apart and thoroughly check it out, particularly the main jet. Do whatever it takes to ensure it is not obstructed including carb cleaner/soak, compressed air blow etc.<br /><br />Maybe this will work for you.