50 HP Merc 500 Not running right need help

bthomsen

Cadet
Joined
Jul 22, 2014
Messages
8
I have a 1974 Merc 500 50 HP that I just had the fuel pump and the carbs rebuilt. I just got the boat and have never had it in the water before this so I'm not sure of how it ran before I got it. The engine Idles good but when I put it in the water when I try to apply throttle it does not gain any RPM's. The boat just sits at idle. The compression and spark are both good. The boat will speed up if I physically turn the distributor myself and engaging the carbs. I have a couple ideas but I figured instead of guessing I would actually ask for advice for once.
 

Redwing4900

Petty Officer 3rd Class
Joined
Aug 21, 2012
Messages
82
Throttles hooked up correctly? I don't mean to offend you, but it could happen. Also are the throttle cables functional. It seems like a simple solution should be the answer here.
 

Chris1956

Supreme Mariner
Joined
Mar 25, 2004
Messages
27,036
When you turn the distributor are you in neutral or in gear in the water? If the motor revs up when you turn the distributor while in gear, in the water, the throttle cables or linkage are suspects. If the motor revs up in neutral, when you turn the distributor, it is a non-test.

Remove the wrap cowl and advance the throttle and see what the distributor does.
 

bthomsen

Cadet
Joined
Jul 22, 2014
Messages
8
Sorry it's been awhile but after further investigation it turned out that somehow during the drive to the lake the throttle cables came loose. All is well and the motor runs great. Thank you everyone for the input.
 

GA_Boater

Honorary Moderator Emeritus
Joined
May 24, 2011
Messages
49,038
Thank for the follow up, bt. It doesn't happen enough. :thumb:
 
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