95 Mariner 4 stroke 9.9

[skip44820]

I have a 9.9 4 stroke Mariner that's nearly impossible to start without the use of carb cleaner. I have had carb off 3 times and it appears to not be the problem. Rebuilt fuel pump cause cost of new one is rediculous. It's pull start and I'm arm weary before I get it to fire. Primer bulb is hard. There is no choke or inricher on this motor. What am I missing. Thanks as always

 

[boscoe99]

Any idea as to the complete model of the motor?

 

[skip44820]

9.9 MLA4S. SER NO OH007035

 

[flyingscott]

Looks like the top of the carb has a primer on it. Make sure it is working.

 

[skip44820]

Looks like the top of the carb has a primer on it. Make sure it is working.

How do I tell if it working?

 

[Faztbullet]

Thats a auto primer, passage closed when cold an not running, heats up when engine running and withdraws into primer body to unchoke

 

[boscoe99]

The cold start fuel enrichment component is what Yamaha calls a Primestart device. Mercury calls it a Primer Assembly. Allows extra gasoline to flow when the motor is cold. Progressively provides less extra gasoline as the motor warms up.

When the carburetor was removed was it completely dismantled and thoroughly cleaned in a heated ultrasonic cleaner? Then reassembled to factory specifications?

If the primer bulb is tight then that should rule out the fuel pump. At least from a starting perspective. If a new pump is required it might be priced lower under the Yamaha part number.

 

[skip44820]

I wish someone would tell me how to check if the choke is working

 

[flyingscott]

If it's cold it will be down if hot it moves up

 

[boscoe99]

I wish someone would tell me how to check if the choke is working

There is no choke.

Difficult to say how something that does not exist works.

 

[boscoe99]

I believe that your carburetor also has an accelerator pump. Have you looked into the carburetor while rapidly advancing the throttle to see if a bit of gasoline is being sprayed into the throat of the carburetor?

 

[skip44820]

I bought a fuel enricher and just had time to put it on, and still no start.

I believe that your carburetor also has an accelerator pump. Have you looked into the carburetor while rapidly advancing the throttle to see if a bit of gasoline is being sprayed into the throat of the carburetor?

no but I will

 

[skip44820]

I am at my witts end, I am about ready to dissamble and sell parts on ebay to try to get some of my money back. I put 12 volt directly to the enricher and it did not do a thing. Is this right. This is outside of carb. I would have thought it should have moved.HEPp

 

[boscoe99]

Was the Primestart device removed from the carburetor? When cold the pin should be retracted. Applying 12 DC volts will cause the pin to extend but it takes time. Minutes. Slowly. It does not happen quickly.

 

[skip44820]

Was the Primestart device removed from the carburetor? When cold the pin should be retracted. Applying 12 DC volts will cause the pin to extend but it takes time. Minutes. Slowly. It does not happen quickly.

I have no idea what Primestart is

 

[boscoe99]

See post #7.

 

[guy48065]

You have to bench test to see if it works. They're pretty slick when they work properly. Scooter engines also use these same primers.
Here's a very thorough YouTube showing how to access, remove & test (on a Yamaha OB):

 

[skip44820]

You have to bench test to see if it works. They're pretty slick when they work properly. Scooter engines also use these same primers.
Here's a very thorough YouTube showing how to access, remove & test (on a Yamaha OB):

Primestart has been removed. One of u mentioned accelerator pump, not sure if that is working. Looking thru front of carb and pulling the throttle on carb don't c any fuel being injected into engine

 

[flyingscott]

How about you buy the manual and do the tests.

 

[skip44820]

I am too, old to do any tests and I got a manuel