'53 Super Fastwin......it wants to run. It really does! EDIT: IT'S ALIVE

[mark in new jersey]

Re: '53 Super Fastwin......it wants to run. It really does!

Re: '53 Super Fastwin......it wants to run. It really does!

it's not "leaking" i.e. "overflowing"......the float / needle is working just fine.

I'm saying that after an hour of pulling on the rope, there's drip-drip-drip out the front of the carb (at the un-gasketed meeting with the silencer). This is "carb throat accumulation", not "uncontrolled over-filling"

 

[OptsyEagle]

Re: '53 Super Fastwin......it wants to run. It really does!

Re: '53 Super Fastwin......it wants to run. It really does!

Fuel coming out of the carb throat is also a symptom of bad reeds/leaf valves. If they don't close properly the fuel that was sucked into the crankcase gets shot back out of them into the carb throat. I would think the reeds for both cylinders would need to be malfunctioning to keep the motor from not running at all, but I suppose that is possible.

I am not sure about your carb throat accumulation theory. If the fuel wasn't being sucked into the cylinders, it would not even be sucked into the carb throat. If it was sucked into the carb throat it should be sucked into the cylinders and out its exhaust, even if the motor was not running, unless it is pushed back out of a bad reed valve or your inlet valve is leaking. If you are sure the inlet valve is OK, I might suggest that it is time to look at those reeds.

In any event, at least we know it is not your fuel pump, which is why we stressed doing the test you did. You can thank Daviet for that. Perhaps others have some thoughts on this new information.

 

[nwcove]

Re: '53 Super Fastwin......it wants to run. It really does!

Re: '53 Super Fastwin......it wants to run. It really does!

....this motor wont even sputter with a few drops of fuel in each hole? but made a kick with without the carb? sure sounds like its getting flooded .

 

[HighTrim]

Re: '53 Super Fastwin......it wants to run. It really does!

Re: '53 Super Fastwin......it wants to run. It really does!

What is your starting procedure, step by step?

Sounds like a float issue or a needle/seat issue to me, flooding.

Dont try tinkering with the float needles, you will never get it right. Go get a carb kit and Ill bet she will fire up.

 

[mark in new jersey]

Re: '53 Super Fastwin......it wants to run. It really does!

Re: '53 Super Fastwin......it wants to run. It really does!

nwcove: I don't suspect flooding because if it were, fuel would run out the exhaust port and into my water bucket. There's *zero* sheen on the water's surface. No fuel/oil is coming out the exhaust tube.

HighTrim: the carb was rebuilt with a kit. all wearable components are new.

A visual exam of the carb shows the float to be level, and the needle drops down when the float drops. It seats when the float rises.

Starting procedure: fuel gravity fed into the carb, low-speed needle backed out 1 turn, high-speed backed out 2. Choke out, rope pulled (and pulled and pulled and pulled)

Choke in.....no difference.

Spark is great, air is assumed to be good.....gotta be fuel.

....or messed up leafs. *if* the fuel is being sucked in, then blown right back out on the downstroke of the piston, that could be a problem. I need to remove the manifold & see what I see. But not tonight.

Thanks for your patience,

mark

 

[64osby]

Re: '53 Super Fastwin......it wants to run. It really does!

Re: '53 Super Fastwin......it wants to run. It really does!

Have you tried spraying some premix in the carb to see if that gets her sputtering. Might be worth a shot before you dig deeper.

I know that I rebuilt a carb and the motor wouldn't fire, turned out some junk from the new fuel lines ended up in the carb, blocking the idle side. Just because it new doesn't mean it's clean.

 

[HighTrim]

Re: '53 Super Fastwin......it wants to run. It really does!

Re: '53 Super Fastwin......it wants to run. It really does!

High speed needle should only by 3/4 of a turn out from seated, the low 1.5 turns out from seated. Fine tune from there once on the water and under load.

Faulty reeds are extremely, extremely rare on these 50s OMCS, I have literally hundreds of them that are mechanically restored, and I cannot think of 1 that had a faulty reed plate.

I am going to be honest, you may be overthinking this. As the old saying goes, keep it simple.

 

[mark in new jersey]

Re: '53 Super Fastwin......it wants to run. It really does!

Re: '53 Super Fastwin......it wants to run. It really does!

High speed needle should only by 3/4 of a turn out from seated, the low 1.5 turns out from seated. Fine tune from there once on the water and under load.

I have seen those settings in one manual I have.......another states the 1 & 2 as mentioned above. I can't see how such a difference could make the difference between running or not firing whatsoever. Running poorly vs. well....sure. But refusing to start at all?

Faulty reeds are extremely, extremely rare on these 50s OMCS, I have literally hundreds of them that are mechanically restored, and I cannot think of 1 that had a faulty reed plate.

I find myself agreeing, but I'm running out of things to check. That said, it's easy enough to remove the manifold cover, yank the rope & see if the reeds are deflecting inward & closing in a oscillatory way....should be a 2 minute verification. One if forced to wonder: did I reassemble it incorrectly?

I am going to be honest, you may be overthinking this. As the old saying goes, keep it simple.

I wholeheartedly agree! These are NOT sophisticated devices. This thing should fire right up. Whatever my issue is, I'm sure it's dumb & small.

1.) verify the reeds are moving
2.) maybe spray some mix into the manifold hole & see if it will kick. That means the issue is virtually certain to be found in the carb.
2.) back to the carb.....perhaps a re-re-build is in order.

 

[Chinewalker]

Re: '53 Super Fastwin......it wants to run. It really does!

Re: '53 Super Fastwin......it wants to run. It really does!

Okay - new to the thread. A few observations...

Easy enough to check the fuel pump. Hook up the fuel line, prime it up with the bulb, then undo the fuel line running to the carb from the pump and direct it into a coffee can. Pull the motor over and note whether it is pulsing fuel into the can. Pulsing fuel - pump is working.

The fuel dribbling out of the carb after numerous pulls, particularly with the choke on for awhile, is normal.

What are the compression numbers?

 

[mark in new jersey]

Re: '53 Super Fastwin......it wants to run. It really does!

Re: '53 Super Fastwin......it wants to run. It really does!

Okay - new to the thread. A few observations...

Easy enough to check the fuel pump. Hook up the fuel line, prime it up with the bulb, then undo the fuel line running to the carb from the pump and direct it into a coffee can. Pull the motor over and note whether it is pulsing fuel into the can. Pulsing fuel - pump is working.

I got a great deal [free] on a crazy-clean cruise-a-day tank, and I have some brand-new 2-line hose, so once I get this to run, I'm reverting to a 2-hose system. That said, I did as you suggest, and the pump works.

The fuel dribbling out of the carb after numerous pulls, particularly with the choke on for awhile, is normal.

Can you explain the physics of that? Others (in this thread) have indicated that it's indicative of bad reeds that are not closing.

What are the compression numbers?

cold = 100 top & 95 bottom. If I ever get it hot ( ), I'll let you know those numbers!

 

[Chinewalker]

Re: '53 Super Fastwin......it wants to run. It really does!

Re: '53 Super Fastwin......it wants to run. It really does!

The physics? You're trying to draw fuel into the motor, but blocking off the air source (choke on), so the motor's crankcase vacuum draws fuel from the carb bowl through the main jet. Lacking enough air to fully atomize it, it will accumulate and puddle in the carb throat if the motro doesn't start. Normally, this isn't an issue, as the motor should start, choke gets shut off, air flow increases and the excess fuel is drawn into the motor. Too much choke, lack of starting, etc. and that puddled fuel will eventually dribble out the front of the carb.

100 & 95 is plenty for starting.

What do you have for fuel? FRESH regular gas, mixed at 24:1?

 

[mark in new jersey]

Re: '53 Super Fastwin......it wants to run. It really does!

Re: '53 Super Fastwin......it wants to run. It really does!

thanks for the perfect explanation.....makes sense.

The gas is new... 87 octane, mixed 24:1 with SAE30 [non-detergent] oil.

EDIT: correction.....I have no idea why I stated 24:1.

It's mixed 16:1, per the engine's spec. (8oz of oil to 1 gal of gas.)

 

[Chinewalker]

Re: '53 Super Fastwin......it wants to run. It really does!

Re: '53 Super Fastwin......it wants to run. It really does!

Skip the SAE30. That's all they had back in '53, so that's what was on the original instructions. 2-stroke oils are MUCH improved today and I would recommend using modern TCW3 rated oil. They burn cleaner, lube better, mix with gas better, foul fewer plugs, and smoke less.

After a starting assault, how do the plugs look? Wet? Dry?

 

[mark in new jersey]

Re: '53 Super Fastwin......it wants to run. It really does!

Re: '53 Super Fastwin......it wants to run. It really does!

Thanks for the oil recommendation. If I ever get this thing running, I'll mix a modern oil into the tank.

(Right now I'm using a very small [but appropriately-mixed] fuel supply. No sense in filling up the tank because a.} this is still just a test, b.} gas goes bad, and the "season" is over, so I don't want to be storing a bunch of mix and c.} I don't own a boat.)

the plugs are bone dry. No fuel is making it into the combustion chamber.

Were fuel getting that far (and not igniting) I would have gas coming out the exhaust port and I'd have an oily sheen on the water bucket.

The exhaust port is dry; The water has no sheen at all.

 

[OptsyEagle]

Re: '53 Super Fastwin......it wants to run. It really does!

Re: '53 Super Fastwin......it wants to run. It really does!

As I see it, it can really only be two things. Either the carb inlet valve is leaking and you are flooding the motor or your reed valves are malfunctioning. The leak in the carb inlet valve is easy to test when the carb is off the motor. Just allow the float to close the inlet valve and blow into the fuel "in" nipple and see if it restricts your blow. You can lift the float and then see if it allows air and shuts again, this way. The other way would be to simply give it time for any flooded gas to dissappate, clean up what you can and then re-hook up the gravity feeded fuel line and just watch it to see if it starts to flow out the carb throat. As we have stated, it should stop when the inlet valve closes, so if it doesn't, that is your problem...or at least a problem.

If it does shut off the flow you could try spraying some pre-mix into the carb throat again. Now if it still doesn't fire, I would start to look at a reed problem. There is only two problems, with the bad reed theory and those are firstly, that it is unlikely that both cylinder reeds would fail at the same time, but it happens, but secondly, if you put a teaspoon of pre-mix in each cylinder, it should fire, even with bad reeds. I think you did this, but you could try it again when you are more sure the flooded gas is gone.

 

[mark in new jersey]

Re: '53 Super Fastwin......it wants to run. It really does!

Re: '53 Super Fastwin......it wants to run. It really does!

progress, I think....you guys be the judges.

I braced the motor stand, squirted some mix directly into the carb port.....

and gave a mighty yank

She fired right up on the first pull.

I repeated the test 4 times, each time with the same results: fired right up.

Mind you, I only squirted a very tiny amount of fuel each time, so it never ran for more than 2 seconds at a time (nor did I want to run it long, since it wasn't in water)......but I'm prepared to call the reeds "A-OK"

But this makes me scratch my head: On Saturday, if there was fuel in my carb body ( it dripped out, so then it was present), and if I now know that the reeds are willing to "suck", why didn't it at least fire up...if only just for a moment...with the carb in place on Saturday?

Again: the engine wasn't flooded....none of the signs of being flooded were present, it was showing signs of being starved.

spark...yes
air...yes
compression...yes
reeds / suction....good
fuel in carb, at least in some fashion.......yes.

I'll take another look at the carb, but I'm prepared to re-install it & do another gravity feed test.

Getting close.....just not there yet.

And I REALLY appreciate all of the support you guys have shown!

 

[Daviet]

Re: '53 Super Fastwin......it wants to run. It really does!

Re: '53 Super Fastwin......it wants to run. It really does!

Well, I think you have proved that the problem is fuel delivery. You could put it in the water and keep it running all day if you wanted to keep squirting fuel into the intake. I think you have confirmed that you have a carb or fuel pump problem. I have been away for awhile and did not go back and read all of the posts, did you convert it back to the double line pressure tank?

 

[nwcove]

Re: '53 Super Fastwin......it wants to run. It really does!

Re: '53 Super Fastwin......it wants to run. It really does!

puts it right back to the carb.....maybe?

 

[HighTrim]

Re: '53 Super Fastwin......it wants to run. It really does!

Re: '53 Super Fastwin......it wants to run. It really does!

Time to revisit that carb, something is wrong.

 

[64osby]

Re: '53 Super Fastwin......it wants to run. It really does!

Re: '53 Super Fastwin......it wants to run. It really does!

That's good news. I'd say it's time to revisit the carb, maybe the re-rebuild will do the trick.