Suzuki DT6 will bot get fuel

[drumbeater]

I been working on this thing for a few weeks. I think its an 86 model but not sure. I've rebuilt and had ultrasonic cleaned carbs, fuel pump has new parts, new plugs, new fuel. I pull and pull and pull and the sparkplugs stay dry.
I've got spark. Bowl in carb is full of gas. There is just no gas going to the sparkplugs, they stay dry as a bone. Just a little residue from old oil and some seafoam I sprayed in there to loosen things up. Compression is 100 in top cylinder and 120 in bottom. Not perfect, but good enough for it to run I would think.
I will say I have no wiring diagram, so I assume all wires are connected, but if the plugs are dry that really doesn't matter, right??

HELP! I'M ABOUT TO THROW IT IN THE DUMPSTER.

 

[drumbeater]

Sorry "Will not get fuel"

 

[Ted]

Will not get fuel

Check to make sure that the fuel shut off valve on your gas tank is in the OPEN position? Also make sure the vent screw on the fuel fill cap is allowing air into the tank. Check the fuel supply hoses for blockage, kinks, or collapsing. Check the fuel connector at the engine. Check the fuel pick up tube within the tank. Some tanks have internal filter screens on the pick up tube. Check fuel filters. Make sure the float isn't stuck and the jet is clean.

Oops, I just re-read your symptoms and see you have gas in the bowl. Some of my suggestions won't apply.

 

[RubyJean]

Reed blocks

Check to see if the reeds are stuck, possible from varnish. This new fuel they call gasoline builds a lot of varnish when not used for a while. Then check for spark... that's all I can think of at the moment..Michael..

Broken reeds will blow fuel back out through the carb..

 

[kloudie1]

Carb is "clean" but I'll bet you have some gum in the jet passages. Air leak around base of carb is another..
I just went through this exact thing with my leaf blower carb and it was gum in the tiny jet passages. Use a can of pressurized carb cleaner. pull the carb and pull the jet screws out . stick the tube of the cleaner can in the screw hole and you should have cleaner coming out the inside of the throat and the inside of the inside of the float bowl.. be sure to use safety glasses to keep from getting your eyes cleaned out! Good Luck..
Ruby Jean has a good one with the stuck reed valves ..

 

[BobM]

If it is like my similar vintage DT4, remove the fuel tank and dump it out. I had bad gas in mine and you can't just drain it out. The drain pickup is about a half inch above the bottom of the tanks bottom. The pull the jets, as someone else suggested, being sure to count how many turns to remove. This can be challenging because the jets can often be all the way out, but stuck in place rotating. Be careful putting the jets back in for this reason. It is awfully easy to crush the tips if you put them in too tight. I destroyed one on a Johnson 9.9 I had. Try the fuel first.

 

[drumbeater]

The only jets I see is:

Idle screw/jet held in with a spring, I've tried various settings, not sure where to start.

Large jet on top that was screwed all the way in, says "40" on top of it.

Smaller jet in the bowl area that was screwed all the way in. This one draws fuel from bowl.

Still pull, pull, pull and no fuel to plugs. I've pulled a plug and checked vacuum and compression with my thumb. Seems good.

 

[Bill Roosa]

Sounds like the float is adjusted so the fuel level in the bowel is too low. the vacuum from the venturi sucks the gas up and into the intake manifold but if the fuel level is too low you can't get enough air to make the venturi vacuum low enough to suck the fuel up and into the manifold.
This is one of those reverse logic things so think through it twice before bending the little tang that operates the float valve. Lower fuel level means the float floats lower which would mean the tang is bent up to high pushing the valve shut at a lower level. higher fuel level means the tang is bent toward the float to allow it to ride higher in the bowel before closing the float valve.
Good luck

 

[RubyJean]

Just for giggles, see if you have vacuum at the carb when turning over. If the top clyinder is a little lower, it's because the seal under the flywheel is leaking. this is pretty common in 2 cycle outboards, but I don't think this is the problem here. Still leaning towards the reed block, or you have a massive air leak..Michael

I was a certified marine mechanic for several years when younger...

 

[drumbeater]

I tried holding my hand over the intake opening in the block and felt no vacuum. But feel vacuum and compression at the plug openings, both cylinders.
I like the seal leak idea, that would explain alot. I was going down the path of an air leak but couldn't figure out where other than the intake.

The flywheel can spin with one hand easily with the plugs in. I felt like it should have some more resistance in a 2 cylinder engine.

 

[RubyJean]

reed block

Now we know that there is no vacuum from the crank case. Go ahead and pull the reed block. Pretty sure this will lead to the problem. Once you know the reeds are not the problem, the only thing left is the rings are ca-putt. The top seal will only cause a problem with the top clyinder. Your getting closer....Michael..

 

[RubyJean]

Compression

Also, without crankcase vacuum, there cannot be true compression......

Just won't test w/ gauge....

 

[drumbeater]

So getting compression readings with a conpression gauge do not give true condition of the rings, valves, etc? I thought good compression meant all was good. And vacuum/pressure when rotating the flywheel meant the intake/exhaust was working correctly.

 

[RubyJean]

Compression

If you cannot get air into clyinders, it can only compress it's own volume. I'm thinking that the reeds are varnished shut. With out being there to look makes this a little difficult. Just trying to help from 3000 miles away. You might try spraying a little carb cleaner into the reed block, may free the reeds. If reeds are broken you still cannot make compression enough to run. If they are stuck shut, you can't get fuel air mix in. Michael..

 

[RubyJean]

Valves

2 cycle engines do not have valves like your car. The use a reed block to serve the same purpose, some use a rotary valve system, but these are only used on old motorcycles. Michael..

 

[kloudie1]

With the plugs out, it will get enough air to make a compression reading work. I think that Ruby is right on with the stuck reed valves.. Kinda strange that both sets would stick.. Has the engine been sitting for a long time on its rear feet?? like lying with the prop facing the ground and the front of the engine looking up?? That could easily gum the reeds closed..

 

[drumbeater]

I was out of Seafoam Deep Creep, so I sprayed some Mercury Power Tune into the intake and also into the cylinders.
I don't how the PO had it stored. But he told me what a great engine it was when I gave him $250 for it. I should know better after all of the motors I've owned. But he was a nice older guy and I took his word for it. He said it probably just needed the carb cleaned and some fresh gas.
I've got three two strokes in the garage and brought the other two back from the dead with no problems. This one is really got me baffled.

 

[SycloneDriver]

Put a little 2-stroke oil in the cylinders then spray some starting fluid into the carb. Now try starting it.
Try cleaning the carb again, use compress air ( from a compressor ) to blow out the passages.
It sounds like you may have damaged reeds or bad crank seals.

 

[drumbeater]

I'm going to let it soak overnight and check it out tomorrow.
And I hit it with a double dose of carb cleaner and power tune. We'll see of those reed valve plates loosen up.
BTW I watched a couple of YouTube videos in how 2 Strokes work and looking at boat.com parts diagrams I see where all the problem areas are now. Or I think I do anyways.

 

[drumbeater]

Overnight soak didn't do anything. Still wont crank.