What is the best method to break in this engine? The dam print is so small I can't see it even with my reading glasses.

Also the motor seems very loose no pinch at all, in fact I see air bubbles (from the oil on sleeve) at the EX port on compression stroke bleeding past piston?

thanks for the help

Check here. http://www.webra-austria.at/download/motor_e.pdf

Ah thats better thanks. Any Idea on breakin size prop, it says slightly larger with less pitch than what you will be flying.

thanks

Slightly larger, with less pitch...hmmm...where have we heard that before...D-U? Dar?

FWIW one of my Webra .50's was like your .55, with very little pinch and almost no base compression. I ran the first gal. of Powermaster 10% sport fuel through it (flew it ) with 4 oz. of extra castor added to help put a little varnish build up on the piston. The extra oil also helps seal things a bit.
As you might imagine, 1 gal didn't put much varnish on it, but it helped, and after another gallon, it has great compression, and has excellent throttle response. You can see a nice, golden brown coating on the skirt area of the piston, just below the top edge.

How does the compression feel, and how quickly does it leak down if you put some oil in the cyl.?

Thanks for the reply

compression feels pretty good not great, it leaks down very fast. It will hold is't compression for only a few seconds.
You can see it bubbling like crazy by the EX port.

Frank

Man not a good week for buying engines, first the Rossi .53, now this. I think I am done buying exspensive engines.

I hear ya...I read your post about the Rossi![:'(]
I hope their "customer service" takes care of it for you!

Thanks

I cant see how the Webra will recover it its leaking that bad.

Frank

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Personally, I've never seen where having tremendous compression at no/low speed was of much benefit. Neither did the inventor and the manufacturers that installed Dykes rings.

The large diameter/low pitch prop is for bench running - not flying.


Ed Cregger

Not only that but Webra say 30 minutes right at the 4-2 stroke break point.

It's strange though, from the description of the problem given by fc911c I would have said it was a ringed engine but going by that Webra site all GT's are ABN.

Yes I agree strange to say the least, definatly a ABN engine. Not sure if I should run it or send it b ack?

That's a tough call...I know what you mean.

If you loosen the head bolts, does that change any?
Sometimes re-torquing the head bolts can make a difference. Don't think that would void any warranty???

You won't know if its a good engine until you prop it and run it in, I'd go for it and I'll bet it's a real good one.

That's true...it's nice and "free" huh?! Should rev up pretty good...just don't lug it down with too much prop.

After reading about both of your engines, two high quality brands, you need to run them more and worry about them less.

Yes I tried that and there was no change. I wouldn't think so.

yes I will probibly go for it, I am just wainting for Ultra trust muffler.

Thanks

well I put a gallon threw the Rossi and I am seeing a steady drop in rpm. We will see if your right about the Webra. From what I know pistons don't grow and if it was a ringed engine I think I would be more optimistic.

I really think what's needed is better quality control.

Frank, PropTop,


[link=http://www.rcuniverse.com/forum/Tapered%2DBore_Engine_Break%2Din_%2D_Upgraded/m_1850473/tm.htm]Here you go[/link].


Brian, it should be a bit lean of the four -> two-cycle break point.

The little brother of this engine; the .50GT, was the only Webra ABN I ever saw peeling its sleeve.

...And it did it and seized on the spot, during break-in, while I was trying to convince the owner to lean down the mixture...

He tried to claim I had "jinxed" the engine by being there....
A few weeks earlier, after I had published my Hebrew break-in article, he had published an article in his own web-site, saying this Webra must be broken-in as rich as it would possibly run... and proceeded to "proved his point" there, with everybody watching...

I was not gloating! ... I really feel sorry for some lost causes.

I broke in my Webra .50GT pretty lean and it's a great engine.
Spinning an APC 12-4 on my Sig Something Extra...Good power and compression.

-Byron 5% nitro with synth/castor oil
-OS#8 plug

how many rpm`s on that prop???? please I need to compare

Motor is going back, I ran 3 tanks of 5% with extra caster and now motor has zero compression, none.

asmund: 13000+

Test005, thnx.

fc911c, dang You are really out of luck these days, I hope your Webra dealer will threat you better than your Rossi dealer

Well Asmund, one think I don't seem to have a lot of is good luck . I am sure Horizon will treat me right.

Thanks
Frank