Mid to early 90's 3.3hp mercury.

I can't get it started. Replaced the plug and sprayed starter fluid- not even a cough. Spins freely. Ran perfect and put in garage a few years ago.

What's my problem? How do I lose spark from just sitting there?

 

Came to this thread for homo, was disappointed..........anyway



Anyway, does it have fresh gas? Are you sure the plug is actually getting spark?

 

I had a 5 HP Volvo/Penta that I used for an inflatable. It was VERY fussy about the gas. Just a bit too much and it flooded, any less and it leaned out. It also had to be fresh; a month old was enough to choke it.

Dump out the gas if you haven't already. Drop the float bowl and clean it out. Spray the hell out of the jet(s) with carb cleaner. Soak it if you can. Blow it all out with air and fill with fresh fuel. Crank it until your arm is sore and verify it's getting the gas through. That is usually enough to do it.

 

My push mower does this thing where I pull the cord and it fires right off, then shuts right off...wtf?
/ thread jack.
Not sure on your problem...be certain you're getting spark and fuel?

 

Also, when I was having problems getting it to start before I could adjust the carb, it ran pig rich and flooded out the plug. Wet plug= no spark. To fix it, I'd pull the plug, dry it off with a rag and heat it with a lighter. That heat made it warm enough to evaporate the extra gas until it fired. Then I could adjust the mixture to where it ran right.

 

Gas was drained from tank before storage, but I doubt the carb was.

 

Take the carb off, let it soak in a bucket of diesel overnight, clean it out properly. Put in fresh gas and fire it up again.

Add 2-stroke spark fluid if necessary.

 

The coil on my Toro died after 5 years sitting outside under cover. Worked flawlessly until it sat in rain for 2 months.

$56 bought me a coil, plug, air filter, and cutting twine for my weed wacker at a local lawn mower shop. I wish I drove something so cheap on the road.

Edit: BTW, I found the dead coil by wrapping a wire around the plug threads, and then bolting the other end to the block somewhere. I then put a giant socket on my drill and used it to crank the top of the pull start, so I didn't have to yank it a bunch. Very easy to diagnosis.

 

Soaking in carb cleaner now.

Should I be able to remove/unscrew the brass looking piece?





Tough to see, but there was some sediment.

 

Yes that's your main jet, it just unscrews. Make sure it's hole is nice and clean.

 

Yes, it unscrews. Go easy, it's not hard to strip out those threads in the housing.

 

Main jet out, it is small. I should be disassembling more?

Like this stuff? Get out the little pipe with holes by going through the top?

 

It was tight. I even slipped once and scratched it

 

I would disassemble anything like that plate with the bolt, because it looks easy enough to do. Don't be pressing anything apart. That power plunger looks to come out with that brass nut. It may be gummy in there.

How far you go depends on how gummed up it is. It really doesn't look too bad. Get a can of carb cleaner (hint - brake cleaner is not the same stuff) and soak the hell out of it. If it runs off clear, it's clean enough. If it looks like it's still removing varnish, hit it again. Repeat as needed. Blow it out with compressed air, and reassemble.


I find it amusing that in these days of fuel infectors and custom ECUs that knowing how to rebuild a carb is nearly a lost art.

 

Is there any problem mt cannot solve?

Further disassembly cleaning every orifice, prefilled the bowl, fired on first pull!



Here are more of the inner bits:

 

Let's see some pics of the yacht this thing propels.

 

Zodiac, son.

It's on its second inflatable. Used to run around Stamford harbor back in the day. In the last decade it took a lot of trips to the Bahamas on this:

 

You're welcome.

 

Good to see you got this resolved. Was reading through thread thinking "clean the carb, clean the carb" and saw that others pointed you the right way.

The day you learn to clean a carb is the day you learn where the real deals on CL are...