Just can not figure it out

[frog man 63]

Hello here is my nightmare I have a Mercury 85 HP thunderbolt outboard on 15' I think fiberglass glassmaster boat and I can not get this motor to stay running I can get it to start then it does I use starting fluid to get it going i know very little about boats but I am mechanically inclined I do know how to work on stuff so I did all the basics gas spark air fuel got all that I just can I get to sing to run clean the carburetors out I don't know any suggestions thank you

 

[racerone]

Do you have good crankcase compression ?

 

[frog man 63]

Do you have good crankcase compression ?

to tell you the truth I am not sure how to check it on a boat I do know how to use a compression checker tool I own one but that checks the cylinders correct

 

[Scott Danforth]

Stop using starting fluid on a 2-stroke outboard

 

[stresspoint]

as posted by Scott , dont use starter fluid ,i will destroy the rings+ other things like seals and roller bearings."" use a squirt bottle with a 25 /75 fuel oil mix if you choose that route.

the reason why the motor will run on starter fluid is because the small jets in the carbs are more than likely clogged up.
these motors need to be set up spot on before you attempt to run them, which means , dont willy nilly mess with stuff "" that will cost you".
get yoursef an PDF manual and study the base set up , set it up as per and go from there .

clean carbes , then link and sync, the motor should run with a push of the key choke first off , no other intervention should be needed.

 

[flyingscott]

Put up your starting procedure. Are you pumping the ball till hard? Raising the lever to get a high idle? Using the choke? Of you are going to use starting fluid at least use the stuff with lube in it.

 

[frog man 63]

Thank you all for the advice I will stop using the starter fluid Streepoint where do I get a PDF manual I will study it when I get it just point me in the right direction

 

[stresspoint]

some online search should get you a manual , if not for that particular motor ? a same configuration of less or more hp will posibly work for you..
my post was in general, as i am not 100% familiar with the Merk motor you have ? is it a 2+2. many questions need to be answered before tinkering.

hence the reason i use a manual for each motor i work on "unless off course i have worked on many the same , even then i often refer to a manual just to be sure all is correct in my procedures.

 

[racerone]

Not likely a 2+2 motor seeing it is a 85 HP model

 

[stresspoint]

Not likely a 2+2 motor seeing it is a 85 HP model

yea i was not sure if the 85 was2+2 like the 75 .

 

[racerone]

The 75 is not a 2+2 either.---The 2+2 were the 4 cylinder loopers.

 

[stresspoint]

The 75 is not a 2+2 either.---The 2+2 were the 4 cylinder loopers.

the 75 4 cylinder in line i had was a 2+2 .

 

[racerone]

I don't think so , unless it was " jet power " rated.

 

[flyingscott]

the 75 4 cylinder in line i had was a 2+2 .

Never saw a 2+2 75. Give us a pic of this unicorn.

 

[stresspoint]

my bad , it was a flip motor 115 i believe now., thinking of the 75 4 stroke Mariner i had at the same time , old age ..

any ways , back on subject >>

 

[That old Mercury]

my bad , it was a flip motor 115 i believe now., thinking of the 75 4 stroke Mariner i had at the same time , old age ..

any ways , back on subject >>

Hi
I have a question
Did the motor ever crank good after sitting for awhile?

 

[racerone]

What does---"crank good "---mean to you?----Turning over with starter engaged ?---Starting up without stalling?------Sorry the term " crank good " means different things depending on the local dialect I think.

 

[airshot]

Do rhe basics to start, get a facrory service manual, I usually find mine on ebay or craigslist. Don't just clean the carbs, get proper rebuild kits so you have new gaskets, diaphrams needle seats etc. Also proper settings for the carbs after a rebuild. Then a link and syc is needed so the carbs match, this will be in the manual. Compression test on all cylinders just like a car. Spark jump test, spark needs to jump 1/4" gap minimum or spark is weak. If all these components are up to specs, she will run...

 

[That old Mercury]

What does---"crank good "---mean to you?----Turning over with starter engaged ?---Starting up without stalling?------Sorry the term " crank good " means different things depending on the local dialect I think.

I asked the question wrong .
Did the motor work good before and now has the problem?
Or is the motor new to you ?
I have not read a lot of threads here so i dont know the whole story

 

[frog man 63]

It is a new motor to me I will do all the checks that you all suggested and I will let you know the results thank you for all of your help stayed tuned