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atoyot
08-25-2013, 10:00 PM
well i got somethin goin on with one of my out boards that has me puzzled....:dontknow:

..
sooo heres the problem.....
.

.motor runs great, starts great , runs fine under load,
but wont rev out...
even at full throttle it bogs bad.....
.
.
.

.if i take the cover off the engine....
power comes back and performs just fine...
put cover on and again wont go top speeed

it has just stared doing this in the last 2 trips....

..
i have a few ideas what i could be......
but im curious to see what u guys think....
.

.
.any input would be great!
..
.

Tinker
08-25-2013, 10:09 PM
Sounds like the carbs are choking out, exhaust leaking up the leg???

85chevy
08-25-2013, 10:09 PM
is the cover affecting ur air intake?

4skin
08-25-2013, 10:20 PM
Try leaning out the carb a bit might be to rich with cover on
Think like a nitro rc or is the choke part way on

Nutbar
08-25-2013, 11:07 PM
take the carb apart and clean it all out. make sure the fuel tank is clean and no water

Trailjunkie
08-25-2013, 11:12 PM
yep to rich or cover is blocking air intake

redline
08-26-2013, 10:06 AM
Is the spark shorting out to the cover somehow?on my old 115 it would only act up when hot but a cracked coil pack was the problem.

atoyot
08-26-2013, 10:30 AM
Try leaning out the carb a bit might be to rich with cover on
Think like a nitro rc or is the choke part way on

was thinkin that was well
set it to factory reccomendation...
then slowly leaned out all the way till it ran like total shit...(3/4-1 turn)

then back to factory...
then went rich...
same result...

no improvement once cover is put back on

atoyot
08-26-2013, 10:33 AM
take the carb apart and clean it all out. make sure the fuel tank is clean and no water


thats the first thing i did buddy[cheers] ....
had about 10 day runs on her till she started actin up.. checked tank and sock and lines and took carb off rechecked.. made sure no leaks and settings are to factory reccomendations....

went for a rip...same result..
no topend power with cover on at more than 50% throttle.....

.
.

atoyot
08-26-2013, 10:34 AM
Is the spark shorting out to the cover somehow?on my old 115 it would only act up when hot but a cracked coil pack was the problem.

lookin at this did a quick volt/ohm test and everything checks to factory reccomendations for coil/plug etc.....
so no shorts...
but never woulda thaught of that 1....
thanx

atoyot
08-26-2013, 10:35 AM
yep to rich or cover is blocking air intake

settings are correct on the carb but i do think something is taking air away...

atoyot
08-26-2013, 10:36 AM
is the cover affecting ur air intake?

i took the boots off and reinstalled the cover using a flashlight looked inside with cover on.. lots of room nothing restricted...[36]

redline
08-26-2013, 10:41 AM
If there's a crack in the waxy shit on the coil pack, it can short out with even moisture in there. Hope this helps.

atoyot
08-26-2013, 10:42 AM
Sounds like the carbs are choking out, exhaust leaking up the leg???


now after everything i have been trying...
this is what i suspected at first... and suspect now:dontknow:
possible exhaust leak...
im thinkin at full throttle too much exhaust is entering
the cover and the carbonmonoxide etc, is not allowing the engine to get proper air into the carb........
when i take the cover off the exhaust is expelled and the engine can get proper air....
.
:confused0006:
..

.

atoyot
08-26-2013, 10:44 AM
If there's a crack in the waxy shit on the coil pack, it can short out with even moisture in there. Hope this helps.

thanx.. i will try an engine running voltage test next.....
maybe i missed somethin...that would be nice
seems alot easier to change a coil than fix a leg exhaust leak:)

atoyot
08-26-2013, 10:50 AM
[36] thanx again for the input peeps .....
were all thinkin the same things...[cheers]


id like to check if exhaust is leaking into the cover...
b4 i redo anymore to the carb
any ideas on how id check that?
looked with motor running but cant see anything obvious signs of ehaust leakage....

4skin
08-26-2013, 11:47 AM
Leave the cover off problem solved lol

vajayjay
08-26-2013, 08:38 PM
[36] thanx again for the input peeps .....
were all thinkin the same things...[cheers]


id like to check if exhaust is leaking into the cover...
b4 i redo anymore to the carb
any ideas on how id check that?
looked with motor running but cant see anything obvious signs of ehaust leakage....


Put canary under cover, run motor for 10 mins, open cover, see if canary flies away or is dead :D [cheers]

F150HULK
08-27-2013, 08:28 PM
I had similar issue, was head gasket. Easy job

chevy69chevelle
08-27-2013, 09:50 PM
what motor? nobody has asked that yet :P

atoyot
08-27-2013, 10:02 PM
5hp tohatsu.same as nissan....

n thnx rod guess ill try googlin headgasget issues on it.......

see if its similar to what i experiencing

nebowe
08-28-2013, 09:38 PM
Ok...maybe a dumb one but check the advance linkage if a two stroke and see if it is being bound up by latching the cover on (old merc problem) ....just a shot in the dark

Always broke
08-28-2013, 11:25 PM
Sounds like coil pack is shorting when it gets too much heat under the cover happened all the time on the rental boats

atoyot
08-28-2013, 11:41 PM
Ok...maybe a dumb one but check the advance linkage if a two stroke and see if it is being bound up by latching the cover on (old merc problem) ....just a shot in the dark

thanx for the tip....checked... shes all clear under the cover.....

atoyot
08-28-2013, 11:42 PM
Sounds like coil pack is shorting when it gets too much heat under the cover happened all the time on the rental boats

i tested the resistance and the coil is still within factory spec...

but havent tried it hot yet:confused0006:

redline
09-10-2013, 04:15 PM
You get this sorted out yet?

atoyot
09-13-2013, 11:02 PM
no not yet....
it does seem to be an exhaust leak issue into the leg into the cover....
so ill mess with it in winter... run it the next couple times no cover...no probs..

Tinker
09-17-2013, 05:48 AM
no not yet....
it does seem to be an exhaust leak issue into the leg into the cover....
so ill mess with it in winter... run it the next couple times no cover...no probs..

You are welcome ;) should be a rubber gasket between the power head and leg, replace or silicone it ya redneck! The exhaust baffle is leaking inside the leg and not making it to the prop. The only way out is through power head thus exhaust getting sucked back into carbs and choking engine out. Its almost like its happened to me........