RE: Echo BME twin
 

Looks nice! How did you weld it? Doesn't look like Tig, but not quite like Mig either. I welded mine with Mig.

AV8TOR

RE: Echo BME twin
 

No it's tig.

As soon as I figure out how I'll post some video.

RE: Echo BME twin
 

Here is a video.

I run out of fuel right at the end of the video.

http://rcuvideos.com/item/N8BCJ2L4KXVQH2FS

RE: Echo BME twin
 

Cool! Congratulations!

Interesting "test stand". I bet your drill press doesn't have any metal chips left on it! ;)

When I started mine on the back patio, it cleaned the entire patio for me!!

AV8TOR

RE: Echo BME twin
 

Looked very steady Awesome... You guys amaze me:D

RE: Echo BME twin
 

Nice job Ralphb;) is it running on gas/glow?

RE: Echo BME twin
 

Yes it is Gas/Glow:D

That stuff is so awesome, or as my son would say Way Cool.

It's just about right for my Sullivan starter, at least until I get the carb dialed in.
I'm hopeing for a hand startable engine.

I had fuel delivery problems at first but finely hooked up to the right fuel tubing coming out of the tank.

I believe I need to raise the compression or use more Nitro,
I'm getting a fair amount of RPM drop when I remove the glow.

I believe the squish band was around .035. This leaves plenty of room, about .020, to remove from the bottom of the cylinders.
I kept the original rings matched to the original cylinders just to get it running.
I hope to raise the compression first, test and then replace the rings.

Gary will have his 42cc version going any day and it will be interesting to see the difference.

Another friend of mine Jack got his started yesterday on Gas/Glow but he wants to put on a CH-Ignition
that he already has.

So this week end should have lots of action.

RE: Echo BME twin
 

I left the base gaskets out of mine and just sealed with Yamabond, and don't notice any rpm drop when turning the glow heat off....

Are you using a good quality 4 stroke glow plug?

AV8TOR

RE: Echo BME twin
 

I'm using OS four stroke plugs and I used red permatex as a base gasket.
How much clearance between the piston and the head do you have?

I'm going to work on getting it tuned tomorrow.

It doesn't seem to draw fuel very well, perhaps the needle needs to be open a little more.
I was having issues with my prop hub as well. It should be okay now.

RE: Echo BME twin
 

Trouble in Paradise.

With about an hour on my twin I went back to the shop because I just didn't like the way it was running.

The last time I ran it and after it was warm it didn't want to throttle up.
I figured it was breaking in and needed a Carb. adjustment or something.
It was pretty warm the last time I ran it, but not over heated.

I noticed air in the line so I turned the prop over by hand.
Well it felt like it was binding up. Not under compression but in mid stroke.
So I took it apart and found the crank was bent.

When the guy welded it he welded it on the end of the counter balances, not as shown
in the welded crank pictures I posted earlier.

I didn't fit my crank my self so I can't say for sure how good of a fit it was but Jack is a perfectionist.

Any ideas?

One thing about parts are pretty cheap "FREE" so I'll just be out the labor.

RE: Echo BME twin
 

Hi Ralph, have you solved the problem with the bent crank on the Echo twin?

RE: Echo BME twin
 

Maybe.
The guy who put them together didn't pin them and only welded on the on the outer edge of the counter weights.
This is not how we had agreed to put them together.
He still says that it is strong enough the way he did it.

It does appear that something metal went through my engine.
There were metal fragments in the engine and a deep score in one cylinder.
He says that is why the crank bent, I'm saying the crank would not of bent if it had been done the way we talked about it.

So I've been working on my Cub and thinking about the twin, hoping to come up with a better idea?

RE: Echo BME twin
 

Ralph, did you check your reed assembly to see if one of the metal petals came apart? Maybe a wrist pin keeper? None of that would cause a lock to bend or twist the crank in my mind.

RE: Echo BME twin
 

The reeds are fine as is the everything else, except the scored piston, cylinder and bent crank.
I believe it ingested foreign material.

Do you think 3/8 of an inch of weld on the ends of the counter weights would be enough to hold the cranks together?

RE: Echo BME twin
 

I would think from the welds in the pictures you posted that you would be fine. I recall talking to Keith about this and he said they just tacked them as your picture shows. I asked about tacking the stub of the crank and he said it wasn't necessary. All they did in the past was pin a few.

RE: Echo BME twin
 

The picture of the crank I poster was not the crank I used, Keith did that crank.
I had the 1st crank done and installed by the time I got this crank.

Here are pictures of the replacement crank.

RE: Echo BME twin
 

I specifically did not weld the crank like that, both for strength and maintaining centering, (at least to my way of thinking), and because I didn't want to heat up that area and take a chance of overheating and/or weakening the rod pin or roller bearing.

You might check to see if the "foreign object" wasn't a piece of rod roller bearing....

Anyone have crankcase or two they would like to sell??? Keith said he sold the last of them to someone in California that participates in this thread, and that he told him I would want a couple. Don't know who it is...

AV8TOR

RE: Echo BME twin
 

All the bearings and cages were there.

3 of us gave it the once over and found everything where it was suppose to be.

I don't really have an answer.

RE: Echo BME twin
 

Ball and/or spring out of the choke detent??

Just guessing...

Hope you get it going again soon.

AV8TOR

RE: Echo BME twin
 

this may works , stroke 35mm:D

RE: Echo BME twin
 

Ok, I'll bite.... what is it out of, or did you make it??

AV8TOR

RE: Echo BME twin
 

av8tor: looks like that $10 crank got your attention!! Getting somewhat better..... Capt,n;)

RE: Echo BME twin
 

Yeah, I probably wouldn't have commented if I had noticed whom it was from. He has a tendency to make posts and then not answer when they generate questions.

Oh well...

AV8TOR

RE: Echo BME twin
 

I see what you mean.....that guy just likes to tease us! Like you say...Oh well. Capt,n

RE: Echo BME twin
 

this is my new cranksift for 120CC. I use Zenoah G62 cylinder and make it as twin 120CC . think this engine maybe more powerfull than most 100CC engine in the market like 3W106 OR DA100. little heavy for sure, but who care about few oz ;)