'77 9.9...no go!

chris in va

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I bought this thing for $300 a few months ago. Last night I changed the water pump and swapped in the 15hp carb, with a fresh rebuild kit to boot.<br /><br />Trying to start it today, it was really grumpy and would only run for a few seconds then quit completely or misfire on either cylinder. After a while it simply didn't start at all no matter what I did, including taking out the plugs and cleaning the gaps. <br /><br />I really think it's ignition related. Before I go blowing $$$ on new coils and pack, anything else I should know? It was no fun putting around with the B&S 5hp in windy conditions with 3 people today.
 

fireman57

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Re: '77 9.9...no go!

Leave the 9.9 carb on it and see if it runs. If it does then keep the 9.9 carb as the 15 carb won't help your performance. There are a ton of posts on converting 9.9 to 15 that you should read. Do a search on this topic fromt the top of this page.
 

20/20

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Re: '77 9.9...no go!

Originally posted by chris in va:<br /> I bought this thing for $300 a few months ago. Last night I changed the water pump and swapped in the 15hp carb, with a fresh rebuild kit to boot.
Why did you jump into a bigger carb? was the original missing? Did you check the filter/pump on the side of the engine? how are the gas lines, any filters, tank etc...? What is the overall condition of the engine? good idea changing the impeller, how are other gaskets?<br /><br />
Trying to start it today, it was really grumpy and would only run for a few seconds then quit completely or misfire on either cylinder. After a while it simply didn't start at all no matter what I did, including taking out the plugs and cleaning the gaps.
Did you check the spark, also how about new plugs points and condenser{about $35 +or- a few $}? Maybe all they need is an adjustment. Also check all the wires if they're old they can/will crack or get worn. <br /> <br /> Fireman57 also made a good point check out the site it helped me alot. It is long so be ready for some reading but it is worth the effort.
 

umblecumbuz

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Re: '77 9.9...no go!

Chris - Fuel?<br /><br />If you're using last seasons fuel, you'll have big probs trying to start it - especially if it's a cord start.<br /><br />Just a thought.
 

chris in va

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Re: '77 9.9...no go!

Well, I've read just about every 9-15 conversion post there is and understand the only difference with my '77 is the carb, so adding a few extra top-end ponies wouldn't hurt. The carbs are certainly identical except for the throat diameter. But I can swap them back out just to be sure.<br /><br />'77 was the first year of the CD ignition module, replacing the points. <br /><br />Fuel, could be old. I'll try getting some fresh in there today. I still really feel it's an ignition problem though.<br /><br />The motor is in fair shape, some corrosion from saltwater use. When I took out the water pump the gaskets were still intact as was the impeller and I suspect someone swapped it out at some point due to the housing being plastic (older ones were pot metal?).<br /><br />I've been following the Puget Sound Anglers instructions which has been very helpful.
 

fireman57

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Re: '77 9.9...no go!

Do a spark test and make sure that they jump a good 3/8 to 7/16". If they don't then suspect a bad coil or powerpack.
 

Chinewalker

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Re: '77 9.9...no go!

Check the wires on the kill switch to make sure they're not pinched or shorted out against something...<br /><br />- Scott
 

20/20

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Re: '77 9.9...no go!

Chris sorry about the point idea I was thinking you had a 75{my bad}. You are correct the carb should not make a difference unless there is something wrong with one of them. Lets us know about changing gas and spark test.
 

fireman57

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Re: '77 9.9...no go!

Did it run with the 9.9 carb? Might need to rebuild.
 

chris in va

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410
Re: '77 9.9...no go!

Alright guys, I'm about to shoot this thing with my 20ga. <br /><br />It's got decent spark on both plugs, I had it running (sortof) with the 15hp carb, but then it just QUIT. My arm is about to fall off.<br /><br />Did the cutoff switch bypass, no change. Cleaned off all the wire contacts to the block, etc. Tried 3 different plugs. <br /><br />Swapped in the 9.9 carb, it sputtered a couple times, then quit again. <br /><br />Now I *know* it's got spark, and seemingly getting fuel. <br /><br />Now what?
 

chris in va

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Re: '77 9.9...no go!

Any ideas before I take my 20ga to it? <br /><br />Everyone I know said to "get a Johnson, they're the best". :mad:
 

umblecumbuz

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Re: '77 9.9...no go!

Chris,<br /><br />You've apparently got a good spark. Presume the fuel's recent, and presume you're sure that it's getting to the cylinders.<br /><br />S0 - Basics - have you done a compression test?
 

Chinewalker

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Re: '77 9.9...no go!

Yep - back to basics....<br /><br />Compression, plus fuel, plus timed spark, equals a running motor (usually). <br /><br />Have you actually been into either carburetor? Are they clean - spotless clean - inside?<br /><br />Is the fuel pump working? Pull the line off the carb and move it over the edge of the cowling into a coffee can. Pull the motor over and note whether you're getting fuel pulsing into the can.<br /><br />Are you getting full advance on the throttle in neutral? I've seen some of these motors get a little wear in the linkage to the point where they don't advance the throttle at all in neutral. I like to set them so that the throttle arm JUST opens up a bit when full neutral throttle is applied.<br /><br />- Scott
 

chris in va

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May 4, 2003
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Re: '77 9.9...no go!

No compression check yet. I did pull the hose already and it squirted fuel really well when I squeezed the bulb, but didn't try when pulling the cord. The recoil spring somehow sprung back into the housing, so yet again I have to take the :mad: thing apart.<br /><br />Is there some writeup as to how the fuel pump is put together? I don't think the holes are lining up right after looking at the way the diaphragms are assembled.
 
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