Association Forum - Anyone have similar Prob w/ Yamaha OB

Assn Members Area · Join

Home.

Association Forum

Ships Store

Cruising

Racing

Technical Tips

Photo Gallery - New

Boat Search - Updated

Manuals & Brochures

Swap Meet

Links

Officer Flag Line & Staff

Bylaws & Constitution

Members Area

Join the Association

Notice:
The advice given on this site is based upon individual or quoted experience, yours may differ.
The Officers, Staff and members of this site only provide information based upon the concept that anyone utilizing this information does so at their own risk and holds harmless all contributors to this site.

Association Forum

Username:	Password:
Save Password
Forgot your Password?

All Forums

Catalina/Capri 25/250 Sailor's Forums

General Sailing Forum

Anyone have similar Prob w/ Yamaha OB

New Topic

Topic Locked

Printer Friendly

Author

Topic

frich
Captain

Member Avatar

USA
418 Posts

Initially Posted - 09/01/2004 : 15:52:22

Hi All!

Well my Yamaha mechanic has mis-diagnosed my problem 3x so I figure I should go to the people who know!

I have a 1988 9.9hp 4 stroke, electric start, hi thrust yamaha outboard. It will not start when the engine is cold unless I put my hand over the air intake. Then it starts right up. I thought it might have something to do w/ the choke, so I have replaced the Bi-metal valve which senses engine temp & the bi metal switching valve.

I should state that the choke is neither mechanical or electrical, instead it is some type of vacuum system. All the hoses look fine and I dont hear any vacuum leaks. Once I start her up, I have no problems for the remainder of the day.
Any ideas??

Thanks
Frank R
84 C25 SK

Edited by - frich on 09/01/2004 15:54:13

Dick Johnson
1st Mate

Members Avatar

USA
40 Posts

Response Posted - 09/01/2004 : 17:58:56

Mine does the same thing. I shoot starting fluid into the air intake. I, too, had it in two times with no luck. I have purchased a repair manual and it offers no clues. Let me know if you get ideas.

Edited by - on

frich
Captain

Members Avatar

USA
418 Posts

Response Posted - 09/01/2004 : 20:22:31

dick

I wouldnt go shooting starting fluid in all the time not good for the cylinder. Instead try what I do put my hand over the air intake just leaving about 1/4 showing, mine starts right up.

I think these carburators are finiky, there all small air passages that can become clogged. If so I dont think the hokey choke vacuum will work. If I find out anything I will email you. Im thinking of calling Yamaha.

Frank R
84 C25 SK

Edited by - on

Bubba
Admiral

Members Avatar

USA
542 Posts

Response Posted - 09/01/2004 : 21:25:15

Is there room to add a manual choke control to the linkage?
Did that to a few cars when I was a kid . . .

Edited by - on

sweetcraft
Admiral

Members Avatar

USA
816 Posts

Response Posted - 09/02/2004 : 00:19:23

Yes, I did take the whole carburetor off and found sediment in the bowl of a 9.9 Yamaha. Really worried that would have trouble with gaskets and parts but gaskets were so good that they were used again and motor started with the auto choke working. Local shop mechanic said gaskets could be used again and gave me the courage to proceed. Engine is in second season after my efforts. Read manual carefully about removing the main jet. There is a small screw that holds the main jet in the correct position. Don't work over water. Turn boat around and have engine over dock or off the boat or the dingy tied under the motor to catch the parts. Jim Cat24 #1490

Edited by - on

frich
Captain

Members Avatar

USA
418 Posts

Response Posted - 09/02/2004 : 06:16:08

You may be on to something here, I rebuilt the carberator over the winter. Maybe the main jet is installed incorrectly? What tips do you have to install this.
thanks frank

<blockquote id="quote">quote:<hr height="1" noshade id="quote">Originally posted by sweetcraft
 Yes, I did take the whole carburetor off and found sediment in the bowl of a 9.9 Yamaha. Really worried that would have trouble with gaskets and parts but gaskets were so good that they were used again and motor started with the auto choke working. Local shop mechanic said gaskets could be used again and gave me the courage to proceed. Engine is in second season after my efforts. Read manual carefully about removing the main jet. There is a small screw that holds the main jet in the correct position. Don't work over water. Turn boat around and have engine over dock or off the boat or the dingy tied under the motor to catch the parts. Jim Cat24 #1490
<hr height="1" noshade id="quote"></blockquote id="quote">

Edited by - on

sweetcraft
Admiral

Members Avatar

USA
816 Posts

Response Posted - 09/02/2004 : 22:51:42

The manual gave me the drawing and position of main jet. You should only be able to install it in correct direction unless you sheared the small screw that is across the shaft the jet is in. When it is clear you can see through it.
Jim, #1490

Edited by - on

Bay Tripper
1st Mate

Members Avatar

USA
56 Posts

Response Posted - 09/03/2004 : 07:18:13

I just purchased a new 9.9 Yamaha last month. The mechanic showed me how to put my thumb over the air intake to help start the engine. I only need to do this when the engine has set for several days. I just had the boat out for a 5 day trip and only had to do the thumb trick the first day. I love the engine for its power in forward and reverse. But I wish they would have installed a manual choke.

Edited by - on

Topic

New Topic

Topic Locked

Printer Friendly

Jump To:

Association Forum

Notice: The advice given on this site is based upon individual or quoted experience, yours may differ.
The Officers, Staff and members of this site only provide information based upon the concept that anyone utilizing this information does so at their own risk and holds harmless all contributors to this site.