I received a used WEBRA 4-40 engine and I'm trying to put it into operation. As far as I don't have any information about the setup of the carburator, I'm want to ask for help here. Do you know the correct setup of the nozzle needles? What is reason for the rear outlet (look at the foto)? The Webra engines have a rotary valve system, is it necesary to check the system for tolerances, and what are these tolerances?
The engines turns smoothly without any major resistance or noise.
I'm looking forward to get some answers.
Thank you and bye.

The rear outlet is simply a crankcase vent, put about three inches of fuel tubing on it and let it hang to vent and drain excess oil oil from the crankcase.

There is no reason to check tolerances. Even if you were to do this, there's no way to adjust them.

John

Mine started easily and ran smoothly on the ground just as it had done on the bench. I tried an 11-4 prop and got about 9500 rpm and a 9-6 only 11,000. I could not get it to idle less than 3000 rpm. Mine would die after 3-5 min in the air. I think mine needs more break-in time and a cooler plug (I used a Fox Miracle)
It may be fine on .20-.25 size planes but it was too wimpy for a 3.5 lb fun fly. I removed it from that plane and didn't have a plane appropriate to use it.

The Webra has an aspin valve induction and exhaust system. The main advantage and reason they were built this way is that you dont have to check for tolerances as they have no pushrods or rocker arms or tappets.

Max

Sorry for the intrusion..

Max, did you get the PM I sent??

Thanks.

Yes , I'll email you back

Chuck,
You could have emailed Max to ask about the PM...

Max,
You could have PM'd Chuck to say that you were going to send an email....



Now, back to the Webra.......

I had one of these back when they first came out. It was a nice little engine. I've still got it in a box somewhere back in ol' Blighty. I wonder if its still any good. Didn't know about after run oil back then...
I used it in a 35-40 sized trainer, it flew it fine. Of course, no-one really flew 'fun fly' or 3D back then either....
Take the front cover off and look at the belt. With any luck you'll see some timing marks on the cam wheels and the cylinder check these line up. Horizon Hobby has spare belts for these engines and probably most other parts too.
I aquired a T4-60 over here but I haven't run it up yet as its NIB and I haven't found a suitable plane for it...

Thank you very much for all the information. Yesterday I got some more information from Webra (Austria) and today I will try go put the engine into service.

Hi!
I ran one of these several years ago using 10% nitro 20% castor oil. I used a 11x6 prop (11x4 is to small and so is 10x6).
Nipple at the rear is for ventilation of the crankcase.
Timingmarks should be found inside if you remove the front cover.
Power is a little less than the first OS FS .40 from the early eighties.

Regards!
Jan K
Sweden