Aluminium carb body question

Thanks for answering,
That will make it a lot easier to build.
Have i understood you correctly that it gave some problems with the bigger space or was it just because you had another venturi?

bnitram

I think it is was mostly the over sized venturi causing it to flood very easily. I had measured the venturis I had at the time, they are much, much larger than the recommended largest size. I cannot quote the size right now, but there is lots of space (over .010) around a 1/8 inch drill bit.

It seemed more difficult to clear flooding, even with the stock size venturi on it. With the stock size venturi we are talking about a handful of flips with the fuel off and glow on to clear, then priming and starting. I never ran a stock venturi on a plastic body for a true comparison on the same engine though.

With the bored out venturi I could get reasonable operation on the plastic body but not the aluminum body. With a stock sized venturi operation is quite easy on the aluminum body, but I don't have a plastic body to compare using the stock size venturi. I am running these engines on bladder pressure.

Phil

Ok,
thanks! I will try it out.

bnitram

I can confirm the aluminum bodies have no flat spot in them to locate and have to be manually clocked correctly. However, the feeling of knowing you'll never over tighten the venturi is worth it. Plus in my opinion it makes the engine look much better. And it'll last forever. With a CNC I would say it would be very possible to replicate the original cox part exactly but not many of us have access to such a machine or the knowledge to run one. In terms of making your own though, the ones currently produced and being sold on eBay are pretty affordable. Often times cheaper than the plastic part. I personally would save time and effort and buy one. And it comes anodized and pretty right out of the package.

Thanks too. Yes you are right. Worktime and so bear no relationship to buy,but I want to design my own RC throttlet carburetor and because i'm a german, i want a metric thread and that request a self made one. It is easy for me...

bnitram

PS:
I also have a lathe and a CNC-milling machine. So it is no Problem.

Oh well then more power to you! Good luck on your endeavor!

Thank you.
You will hearing from me, when it is finish

bnitram

Phil mentioned adding a head gasket or two. Keep in mind, the aluminum units usually come with a teflon washer for the large end, but I like the copper head gasket idea better. And if I recall correctly, also a rubber o-ring for the collet end.

Rusty

Oh yes... You are right... I will look how i will make it...
I think i will make it in 1 or two weeks and then I will report here how it was and work..

bnitram

RknRusty wrote:Phil mentioned adding a head gasket or two. Keep in mind, the aluminum units usually come with a teflon washer for the large end, but I like the copper head gasket idea better. And if I recall correctly, also a rubber o-ring for the collet end.

Rusty

Yes, they do come with the o-ring and teflon washer. The o-ring tends to bind if assembled without lubrication.

The head gasket can help prevent binding as well, and take up space so everything fits better if necessary.

Phil