Re: Puch E50 Engine Air Leak

Does this crank look useable since cleaning it up. I also tested big bearing and no play room and smoothly turns.

The last pic shows my piston connection but there are no bearing. Fits snug with a sleeve. It this normal since it’s stock.

Thanks

415D3A45-00EA-4066-8C5D-B759D5F4731E.jpeg
D3338530-F730-4B2D-A202-6DEC7A77D1A3.jpeg
CCE095B3-0CBA-4163-995D-3EDC2D2EEB9F.jpeg

Re: Puch E50 Engine Air Leak

Stock parts are durable. I would throw new seals on it and run it.

Small end bushing is normal for stock crank.

If you were tryin to build something wild, now would be the time to upgrade. But a good stock crank is nothing to throw away.

Re: Puch E50 Engine Air Leak

That’s my next step. Put it back together.

If the Piston Cylinder is smooth, with no visible scratches. Do I need to hone it?

Re: Puch E50 Engine Air Leak

Are you replacing the piston rings with new?

If you are using the same parts and ring gap is within tolerance, with no serious blow-by and good compression, then no need to hone.

If you do replace those rings, then it is common practice to hone so the two parts can break in together and seal well.

Re: Puch E50 Engine Air Leak

Thanks, I do have new rings

Re: Puch E50 Engine Air Leak

Yeah I'd probably just run it at this point, you could have rebuilt, blown up, and re-rebuilt the engine in less time than we've spent discussing it on here, haha.

If you have a brake cylinder hone or a small dingleberry hone go for it, but if not I wouldn't sweat it.

Re: Puch E50 Engine Air Leak

I have been looking on the internet at e50 motors and never see one like mine. They don’t have this extra valve on the cylinder.

Does anyone know why this one had it. Thanks

image.jpg
image.jpg

Re: Puch E50 Engine Air Leak

As in the decompression valve?

Re: Puch E50 Engine Air Leak

Yes, but nearly every Youtube video I watch doesn’t have it. Weird how mine does.

Re: Puch E50 Engine Air Leak

Maybe the head has been changed in the past? My E50 has one. Did you have it hooked up?

Re: Puch E50 Engine Air Leak

Dirty30 Dillon /

The Stateside e50's didn't commonly have them, but a bunch of the early Euro ones did.

It's better just to replace with a non-decomp head and avoid the complication

Re: Puch E50 Engine Air Leak

Yes, it works fine, just wondered if I need it connected.

After reading post, I guess I don’t (edited)

Re: Puch E50 Engine Air Leak

Update:

1- I rebuilt the seals and tested for air leaks. No leaks anymore.

2- I changed the rings and tested compression, 125psi

3- I rebuilt the carb and tested fuel line and all looks good

4- I teated spark and all good

With all this I thought my problem would be fixed but still no gas getting to cylinder.

I am at a loss. What else can I do to test and determine why this is happening.

The only other thing that bothers me is, on top of my Bing Carb there is a slot. If I connect my pressure test to air filter intake, i hear air leak out of slot. There doesn’t seem to be a good seal between engine intake and carb. Could this cause issues. And why would there be a slot on top of carb. Looks standard.

Any ideas are greatly appreciated.

98C30A22-0F38-4267-8D04-CA405826329F.jpeg

Re: Puch E50 Engine Air Leak

Looking at whatever the hell happened to your carb, there is at least á problem there.

Re: Puch E50 Engine Air Leak

Why do you say this.

Re: Puch E50 Engine Air Leak

This is absolutely not supposed to look this way.

IMG_20210508_212250.jpg

Re: Puch E50 Engine Air Leak

Jim,

When you put that carb onto the intake manifold, did you put an o-ring in there?

Common practice is to have the carb and intake manifold off the engine, on the workbench. Drop the right size o-ring into the carb and press the intake against it with some pressure while you tighten the clamp.

Then, it won’t leak no more.

If there is a crack or something in that body, I have a couple bings and will send ya one if you want. It will hust take a min to get there, so try the o-ring first, eh.

Re: Puch E50 Engine Air Leak

The Bing would not come off so I used a screwdriver to pry it open(multiple time) but its only surface scratches. No issue with tightening.

Re: Puch E50 Engine Air Leak

Thanks will give o-ring a try

Re: Puch E50 Engine Air Leak

why do i feel like im getting punked, when someone needs help, and says "cleaned", and shows a picture of the crustiest looking carb they can find and calls it clean. clean your banjo filter, it'll stop gas flow in its tracks.

Re: Puch E50 Engine Air Leak

Yes, I must agree it looks bad from the outside but I assure you that I tore it all apart and cleaned the internals. I am getting good gas flow, i changed the valve because it wasn’t working well, i cleaned the filter for the gas connection, i ran a small wire through the float intake through to throttle. I replaced the float and gaskets.

I think the carb is good. If the o-ring doesn’t work, I will reach out for another carb.

Sorry moped gurus, i have botched a few items but I assure you if wasn’t my intention. I owned this moped as a 14 year old kid and I am trying to resurrect it as a 57 year old kid. It been in the garage for 43 years. 2 years ago, i put gas in it and it ran like a charm. Then a year later it died and I have been struggling since.

My goal is to get it running again.

Re: Puch E50 Engine Air Leak

jim, with all do respect. im 62, retired machinist at 49, and still a kid that had a puch in my teens. far from guru status i assure you. cleanliness is next to godliness. i rarely take on a bike if it was grossly neglected, or stored deplorably. it is just to much work for what its worth. that being said. you have to think clinically in your approach, and mindful to the original engineering following all required scheduled maintenance. for example that slot on your bing you speak of. it is a perfect place for 40 year old dirt, sand, and grime to fall in your carb. every movement you make. marring all landings and seats. hence the o-ring diy fix. puch i assure you did not assemble mopeds with 40 year old dirt on everything. think about it man. fyi.. i never take a running 40+ year old bike out for a spin without repacking wheel bearings first, and while im at it detail clean maintenance everything damn thing. i gave my first moped to my nephew, and he had fun with it until he neglected to take care of it. now its landfill...... i do wish you success on getting your bike going.

Re: Puch E50 Engine Air Leak

Once I get it going I will repack wheel bearings. For sure a dangerous piece to neglect. I will clean up the outside carb. I already repainted the moped, changed clutch and brake pads. All cables and tire were replaced. Total redo but I should clean up any excessive dirt.

Thanks for the recommendations

Re: Puch E50 Engine Air Leak

Your main jet is clogged. Bing bowl isnt filling up due to float sticking or not adjusted.

Re: Puch E50 Engine Air Leak

i totally fell for it, jokes on me! in the mean time. i get to look at my commuter, it aint purdy, but i love it just the same.

thumbnail.jpg

Re: Puch E50 Engine Air Leak

No, bowl is full and if you push overflow button, the gas leaks out.

I cleaned the jet as well. Just not enough suction to pull I think. I put my finger over air intake and there is suction, but I think my seal between manifold and carb is bad. Hopefully o-ring fixes this

Re: Puch E50 Engine Air Leak

roots to wings /

Does it fire if you put fuel in spark plug hole? Does fuel move freely through your carb with the bowl off?

Re: Puch E50 Engine Air Leak

Yes and yes. There is a good spark

« Go to Topics — end of thread

Want to post in this forum? We'd love to have you join the discussion, but first:

Login or Create Account