Primer bulbs

moedelawn

Member
Joined
Aug 18, 2020
Messages
10
Reaction score
2
The bigger Yamahas come WITH a primer bulb in the rigging box!!
I have one on my f115 Yamaha and f25 never used it after the initial prime. I thought about removing it until I was heading in one evening and some guys had a f70 Yamaha that ran out of gas in the main tank which was on the front of the boat. They had a small gas can and added some gas but with no primer it wouldn't pick up the fuel and the battery was getting weak. I had to connect it to my line and prime it. They were good after that. Not a bad idea to keep one in the boat. I've had to disconnect to remove water that was in the tank.
 

MrGiggles

Well-known member
Joined
Jul 12, 2017
Messages
767
Reaction score
29
Location
Springfield, MO
The bigger Yamahas come WITH a primer bulb in the rigging box!!

I guess I can only speak for the Mercs then.

A primer is not recommended for my 2011 90hp, there is no needle valve in the VST, if you overfill it with the primer, it will trip the vent switch, alarm, and kill the low pressure pump.
 

eeshaw

Well-known member
Joined
Oct 5, 2019
Messages
348
Reaction score
19
I installed a factory primer bulb the other day on my project. I couldn't mount it vertically in the area I have available so horizontal it is. The water seperator had a 3/8 fitting that had to be swapped out for a 5/16, other than that it was good to go. When I get ready to water test the engine I'll have to replace the water seperator canister with a new one.
 

LDUBS

Well-known member
Joined
Aug 14, 2016
Messages
4,284
Reaction score
111
Location
Clayton California
I installed a factory primer bulb the other day on my project. I couldn't mount it vertically in the area I have available so horizontal it is.

I was not aware that they should be used vertically until I read this thread. I may be misunderstanding, but I think what is meant is to hold it vertically when using it. Otherwise it can lay flat? Maybe someone can clarify?

Mine lays flat (horizontal) in the splash well. It is basically unused.
 

MrGiggles

Well-known member
Joined
Jul 12, 2017
Messages
767
Reaction score
29
Location
Springfield, MO
I was not aware that they should be used vertically until I read this thread. I may be misunderstanding, but I think what is meant is to hold it vertically when using it. Otherwise it can lay flat? Maybe someone can clarify?

Mine lays flat (horizontal) in the splash well. It is basically unused.

The check balls in them don't work that well when they're dry. So if you're priming up a dry system, it helps to hold it vertical. Gravity holds the balls in place.

Otherwise I don't think it makes any difference, and once they're full of fuel, they work in pretty much any orientation.
 

RaisedByWolves

Well-known member
Joined
Oct 7, 2017
Messages
623
Reaction score
13
Location
Bucks county PA.
I was not aware that they should be used vertically until I read this thread. I may be misunderstanding, but I think what is meant is to hold it vertically when using it. Otherwise it can lay flat? Maybe someone can clarify?

Mine lays flat (horizontal) in the splash well. It is basically unused.
They "Should" be held vertically, but in my experience as long as its in good working order it will work in most orientations.
 

Latest posts

Top