No Power on High End

shiningstar

Recruit
Joined
Feb 26, 2006
Messages
2
I own a 1987 110 hp Johnson V4 outboard on my boat, and when I push throttle forward it dies out. Can't get over 1200 rpm. I have checked carbs and they are clean. Also checked fuel pump diaphram for leaks and all appears ok. Carbs also seem to be in sync. Anyone (please) got any ideas? Could it be bad fuel from sitting or weak spark. ????????????????????? Thanks for help.
 

ob

Admiral
Joined
Aug 16, 2002
Messages
6,992
Re: No Power on High End

If it has set out of use for a spell ,I'd guess that 1 or more of the carbs have fouled with restrictive deposits.Also you can perform a spark test and insure all leads will jump a 1/2" gap to ground with a crisp blue spark.Other possibility is carb linkage is out of synch but check the above first.
 

MCM

Lieutenant Junior Grade
Joined
Jun 1, 2005
Messages
1,201
Re: No Power on High End

Welcome to the forum Errol,<br /><br />Is this motor new to you? if not has the motor run fine and then just started acting up?<br /><br />Probably need to start with the basics with a compression check (post the results), then do a spark test. Spark should be strong and blue with a real snap and jump about 7/16 of an inch. Its best done using a spark tester, you can do a search and find instructions on building one or you could buy one, iboats has them for sale I think.<br /><br />Should be lots more good advice coming shortly.<br /><br />Good Luck :)
 

newtong_ware

Seaman
Joined
Sep 18, 2005
Messages
59
Re: No Power on High End

Tear those carbs down. I had so many people tell me I had a carb problem and I just could not believe it. Cranked and ran good but "surged" when I tried to give it the gas, sometimes.<br /><br />I tore the first carb down and it was spotless. But then I went into the second and guess what? A nice little chunk of something right where the fuel reaches the needle valve for the bowl. And I wanted it to be something else really bad. I was sure of it.<br /><br />Well, duuuhhh. <br /><br />Check the carbs, tear them down. Carb kits are cheap. If they do not fix it, then go onto something more time consuming and expensive.<br /><br />Oh, and buy a good OEM manual. O-E-M!<br /><br />Good Luck!
 

Solittle

Fleet Admiral
Joined
Apr 28, 2002
Messages
7,518
Re: No Power on High End

You can't tell how clean carbs are by how they look. If the carbs are in sync you can pull them off together for the rebuild. I did it that way on my 1987 110s. I would start there.<br /><br />What other troubleshooting have you done? Don't spend a lot of time on the "it could be's" - You fix these things by finding out what they should be doin, what they aren't doin now and why - then start replacing stuff.<br /><br />Oh - - and a BIG WELCOME!!!
 

OBJ

Supreme Mariner
Joined
Dec 27, 2002
Messages
10,161
Re: No Power on High End

Just to build on the carb area a little, take some premix in a spray bottle and pull the front carb cover off. With a helper at the wheel, have him try to accelerate the boat. When the boat starts to bog down, spray some premix into the carb throats. If the engine picks up, almost asured to be carb related or fuel supply related. <br /><br />But as posted above, check the compression and spark first...if for nothing else, you will have some reference for any other problems in the future that may crop up.
 

shiningstar

Recruit
Joined
Feb 26, 2006
Messages
2
Re: No Power on High End

Hey guys,<br />Thanks for all the info. I've pulled carbs and waiting for kits to arrive before I tear them down. The motor ran fine for the guy I got it from, but it sat up for over a year and half. In the mean time, I will check compression and spark also. Thanks again.
 
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