Typical Mariner/Merc 3-cyl fuel pump pressure

Joined
Sep 21, 2010
Messages
13
Does anyone know what would be the typical fuel pump discharge pressure to be expected on a 1982 Mariner 3-cyl? I have come to the conclusion that the enrichment circuit on mine is not working. The solenoid fires, and the linkage to the side of the carbs actuates, but it has zero effect on a cold start. A couple of squirts of gas into the carb works perfectly every time.

I want to scrap the enrichment works and install a solenoid valve off a tee placed in the fuel pump discharge line, and install a small spray nozzle in the sound box at the carb entry. When I push the key I can open the solenoid and spray a small amount of gas directly into the carb throats. When I release the depressed key, the solenoid valve will close and fuel delivery to the carbs will return to normal through the bowls. This will automate and replace my manual "priming" with a squirt bottle.

I am curious to know what pressure top expect from the fuel pump when cranking - if I have at least 5 psi this should work.

Why in the world did they ever replace simple choke shuuters with this enrichment crap anyway?

Thanks.
 

Faztbullet

Supreme Mariner
Joined
Mar 2, 2008
Messages
15,589
Re: Typical Mariner/Merc 3-cyl fuel pump pressure

This system really gives no trouble as it is a simple opening and closing of a passageway. When closed(choked) extra fuel is routed to primary discharge port behind throttle plate, when opened air is routed thru this passage way. Carbs with to low of a float setting can cause this as insufficent fuel to cover the fuel passage way, it sucks air instead of raw fuel.
 
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