9.9 sputters and dies above 1/2 throttle

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Old PDQ Message Board
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9.9 sputters and dies above 1/2 throttle

Post by Old PDQ Message Board »

9.9 diagnosis

Posted by Dan Hofmann on April 22, 2002 at 07:30:00:

Wondering if anyone can lead me in the right direction on an engine problem

Already changed the carb and ruled that out. Thinking it must be electrical

Problem: start engine just fine,warm it up. When I give it power it spits and
sputters before running up. Under load it will only achieve half power even when
given full throttle. It also does this sporatically. After changeing carb, it
ran twice with out a problem, following morning it would not run up to power. If
I kept it up, it eventually stalled. Anyone who has this problem, I would like
to hear your final fix

Follow Ups:

Re: 9.9 diagnosis Dan Hofmann 03:15:45 04/25/02 (0)
Re: 9.9 diagnosis Bill Fischer 21:20:51 04/24/02 (1)

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Re: 9.9 diagnosis

Posted by Dan Hofmann on April 25, 2002 at 03:15:00:
In Reply to: Re: 9.9 diagnosis posted by Bill Fischer on April 24, 2002 at
21:20:00:


Thanks. Changing out the Carb sort of eliminated a dirty carb. I had pondered
that oil pressure and or a heat/wiring related problem also because that can
also shut you down. I will see if there is a way to test them,again thanks

Follow Ups:

Re: 9.9 diagnosis

Posted by Bill Fischer on April 24, 2002 at 21:20:00:
In Reply to: 9.9 diagnosis posted by Dan Hofmann on April 22, 2002 at 07:30:00:

I have heard that there is an automatic slow down for low oil pressure and that
changing the oil strainer will improve the pressure. It may be the oil pressure
sensor going bad. I am having a similar problem intermitantly. I believe the
previous owner did too. I have also read an article by Charles Kanter talking
about the same problem. most mechanics will say it is a dirty carb, your new one
may have a small piece of dirt. It does not take much.

Follow Ups:

Re: 9.9 diagnosis

Posted by Marc Gershel on April 22, 2002 at 11:39:00:
In Reply to: 9.9 diagnosis posted by Dan Hofmann on April 22, 2002 at 07:30:00:

Hi Dan. Have you checked the anti-siphon valves? I had a lot of problems until I
removed them.Try running from a remote tank to determine if there is an
obstruction in the fuel line. I had a problem where the inner wall of the fuel
line separated & was blocking the flow

Marc

Follow Ups:

Re: 9.9 diagnosis Dan Hofmann 03:38:27 04/23/02 (0)

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Re: 9.9 diagnosis

Posted by Dan Hofmann on April 23, 2002 at 03:38:00:
In Reply to: Re: 9.9 diagnosis posted by Marc Gershel on April 22, 2002 at
11:39:00:


Mark, My problem started on a test stand with fresh fuel. It was just sporatic
enough that I though It was gone when I swithced carb's and she ran fine the
first day I had re installed her on the boat

Thanks for the input
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Post by Phenix-former-owner »

I put this message in this older topic (and changed the title, it's nice to be the moderator!) because it is relevant.

I launched Phenix (32007 with Yamaha outboards) yesterday in East Chicago (3 hours from Chicago, motored all the way). Prior to launching, I had the valves adjusted by my mechanic.

Fuel is from last year, only about 5 gallons in the tank, with fuel stabilizer.

- Everything OK, ran with both engines at about 2800 rpm.
- 30 minutes into the trip, switched to only the port engine, ran for 1 hour at 2800 rpm.
- Switched to only the starboard engine, ran for 15 minutes at 2800 rpm, until ... it sputtered and died.

Restarted, idled fine. As soon as I revved it above 2000 rpm, it died. Tried a few times, same thing. Ran with both engines at 2000 rpm for a few minutes, then revved them both to 2800, starboard engine came up on the 3rd try revving it.

Ran 1.5 hours, both engines at 2800 rpm, reached Chicago, throttled both down to idle to enter the harbor. Revved them back up and starboard engine died. Each time I would rev the starboard engine past 2000 rpm, it would die. Got into the slip OK.

Tried revving the starboard engine past 2000 rpm in neutral, many tries, as I felt it would die so I brought it back down to idle. Finally got it up to 3700 rpm and ran it for about 10 seconds (hoping to get crud out of the engine, if that was the problem).

My first thought would be bad fuel, but if this was the case, wouldn't I have problems with both engines? And if crud is in my 9 year old fuel tank, how can I clean it out?
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Post by Tanah-Keeta »

My experience is to never store the boat with less than full fuel tank. I did and had terrible problems until I had it pumped out. You might look at the accelerator pump on the bottom of the carb. It has a diaphram and a spring but just above that spring in the body of the carb is another spring and ball check valve. Clean it out good and use compressed air to blow it out. My engine would run but not over 3700 RPM. I am guessing your problem is fuel and you now have some water/contaminant in the carb...... although it normally affects the idle first. You also need to install serious filters if you haven't already. I now have 20 micron spin-ons and am going to add 5 micron Racor separators. It is also good to use Stabil in every tank... it helps remove varnish in addition to the storage attributes.
Ron McDaniel
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Post by Phenix-former-owner »

Thanks for all the tips, I hope to get working on this problem in the next few days. Spring cleaning is taking precidence
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Post by Phenix-former-owner »

Ron, I think you might be right that it is water in the fuel/engine. I'll do the cleaning you suggested.

What do you suggest as the best way to get the water out of the fuel tank on the 32? Anyone?
gonesailing

Water in fuel

Post by gonesailing »

You can either add gas line antifreeze or denatured alcohol.

Both chemicals do the same thing because they are the same thing.

They mix with the water (alcohol will mix with water of course, otherwise no boat drinks!).

Then the alcohol and water mix run through the engine and get burned off.

I'd do this three or four times just to be sure.

Most important tips:

Stabilize if leaving fuel in the tank for a winter haul or storage. ALWAYS keep a bottle or three of stabilizer aboard.

If leaving the boat for a long time, fill tank completely to prevent condensation which leaves water in the fuel.

If in a warm climate, add a biocide to prevent growth in the tank.

One last tip... if you have aluminium tanks, check to be sure that they are not mounted on rubber pads. Rubber contains carbon, and in salt water the carbon will react with the aluminium and set up galvanic corrosion. Pinholes in the tank around the rubber will result.
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Post by Tanah-Keeta »

The chemicals for breaking up water.... primarily isopropanol.. are designed for automotive use where you have large carbs to run the fuel through. I did just that on my watered down tank before I left and it continually clogged the very small idle jets in the Yamaha Carbs. I had it totally pumped out and still had to clean both carbs. I did get it to run fairly well by disconnecting the fuel line from the tank and putting it in a 5 gal can of fresh fuel. I would recommend taking the boat to a marina and pumping out all the fuel or get a manual pump and pump it into 5 gal can and use it in your car. I do not use the chemicals (except for Stabil) in my tank any more.
Ron McDaniel
TK III 34108
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Post by Allezcat »

My 2 Cents,
CDI's sometimes cause weird stuff like you describe.
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Post by Phenix-former-owner »

Chet, sorry for the question, but what is a CDI?
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Post by Allezcat »

Kevin,

CDI is abbreviation for Capacitive Discharge Ignition. It is the black box on the port side of the motor about the size of a cigarette box with many wires coming out of it. It controls the spark to both cylinders and often malfunctions causing untold grief. It is a bit of a job to replace but all the wires are color coded. I think a new one runs around $150. There are also resistance tests you can do with an analog ohmeter as outlined in the service manual.
I would try this only after cleaning the carb, cleaning fuel filter on the engine and any prefilters, checking fuel pump(trade with other motor),and removing the anti-siphon valves at the tank exit fittings under the cockpit sole.
Chet
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Post by Allezcat »

Kevin
Another quick thought; Check all the fuel hose connections including the connection at the motor. A loose connection will allow air to be sucked in. Also the fuel hose primer bulbs are notorious for causing problems as they have check valves which malfunction. You might consider a replacement hose, bulb, and connector or a trade with the other side.
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Post by Phenix-former-owner »

This is an update since last year. I continued to have intermittent problems, so my mechanic pulled both engines and rebuilt the carbs and did everything else that might be possible inside the engines (10 years old, fresh water only) to get them good as new so that would last for many more years.

Launched the boat today, motored from Indiana to Chicago, no problems, probably need to make some adjustments to throttle and idle speed. I'll keep you updated here.

Pulling into the slip, I prompty fouled the prop in a line (I was alone). :oops: Of course, I didn't know this, thought the engine just died, so I tried to restart it and then it prompty blew the main fuse on the boat! Not sure why. Somehow, I got into the slip - repair time for the fuse tomorrow when I figure out what to change.

Oh well, another boating season has started. :roll:
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Post by chicagocat »

Kevin,
Glad you got in OK. Too bad about the fuse and all, but sounds like no big deal. I lost your direct email, so thought I'd write you here.

Feel free to call me if you need help next time. I'm always up for a day off work...

I won't be pulling into Monroe for another 3 weeks, but I'm sure I'll see you around. Also, I think I still owe you $ for that harness.

See you soon.
Brendan
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PDQ 36052 - 1996 LRC - "Anne Z" - Chicago
and 2001 PDQ 36 Classic (Tall Rig)- "Cat Tales" - Punta Gorda, FL
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