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-   -   Venturi for 061 Wasp (http://www.rcuniverse.com/forum/1-2-1-8-airplanes-70/10532678-venturi-061-wasp.html)

sealdoggy 05-21-2011 08:36 AM

Venturi for 061 Wasp
 
Anyone know where I can get a control line venturi for a ap Wasp 061

Steve

combatpigg 05-21-2011 10:27 AM

RE: Venturi for 061 Wasp
 
I don't think they exist. I've always tied the carb wide open, but you could make your own venturi by picking up a nylon standoff at the hardware store, then final shape it while it's chucked into a drill press, or even just a drill motor clamped in a bench vise. Nylon can be worked with knife blades as a cutting tool.
I've also done aluminum venturis in a drill press, using a screwdriver as a cutting tool and the table rest as a place to steady the tool.

ggeezer 05-21-2011 01:19 PM

RE: Venturi for 061 Wasp
 
Hi Steve,
I have the same problem, check out the solution I am working with here:
http://stunthanger.com/smf/index.php?topic=20796.0

My tests with this carb mod are not complete yet but I have the Wasp up to 16,100 rpm on a 6-3 Master Airscrew prop, although after more than 40 minutes of break-in, the engine is still tight and won't hold the max. rpm.

Orv.

Mr Cox 05-21-2011 01:57 PM

RE: Venturi for 061 Wasp
 
I haven't tried, but since the AP is a Norvel copy/rip-off, a Norvel ventury might drop right in.

16100 on a MAS6x3 sounds a bit low, try a full castor fuel if you don't have done that already. I think mine did close to 17000 rpm on 10%nitro and 20% all castor.
After 40 minutes it should be close to worn out...

hllywdb 05-21-2011 05:13 PM

RE: Venturi for 061 Wasp
 
The Norvel is oval and the AP is round. One of the few parts they didn't copy outright.

ggeezer 05-21-2011 10:07 PM

RE: Venturi for 061 Wasp
 
I was very careful with the break in. I started with fuel blended for Fox engines (5% Nitro and 29% all Castor) for the first 30 minutes.
I am now using 10% Nitro and 22% all Castor. The engine is still not broken in as the rpm keeps increasing on each run. I'm sure I will hit 17,000. My plan is to slowly enlarge the ventury and increase the Nitro to see how much I can get out of her without needing pressure.

Orv.

uliner 05-22-2011 02:54 PM

RE: Venturi for 061 Wasp
 
Rsm has them venturi's for AP wasps.

http://www.rsmdistribution.com/index-2.htm


If your engine still tight, check the crank, you may need to polish it a little. Some are thght and take forever to break in.

gcb 05-22-2011 07:29 PM

RE: Venturi for 061 Wasp
 

Quote:

ORIGINAL: ggeezer
I was very careful with the break in. I started with fuel blended for Fox engines (5% Nitro and 29% all Castor) for the first 30 minutes.
I am now using 10% Nitro and 22% all Castor. The engine is still not broken in as the rpm keeps increasing on each run. I'm sure I will hit 17,000. My plan is to slowly enlarge the ventury and increase the Nitro to see how much I can get out of her without needing pressure.

Orv.
After reading Orv's procedure, I looked up the online instructions (which Orv is following correctly). Is the Wasp not an ABN setup?

The online procedure appears to follow the old iron/steel process used to heat cycle an iron piston. If I understand correctly, a high silicon aluminum piston does not heat cycle. My understanding is that after the first couple of minutes to wear-in the conrod bearings (and possibly remove residual manufacturing junk), the rest is just slightly rich run time to smoothe crankshaft and piston/cylinder fits.

Is there something different about the Wasp metalurgy?

I don't have a Wasp, but I have some NORVELs (both ABN and Revlite).

George

ggeezer 05-22-2011 08:10 PM

RE: Venturi for 061 Wasp
 
That is an interesting point you make there George, I wondered about that too. I think the box the engine came in either said ABN or ABC on the list of features, although this was covered up with a sticker that says "Hypereutectic Alminal". Now this term is a mystery to me as I have not heard of it before and Google was no help.
The engine definitely has a pinch at TDC like an ABC.
I checked the crank fit and it seems to be OK.
The engine will now run at 14,000 all day and remain cool but if I increase the rpm to 16,000, the cylinder head temperature really starts to rise and the rpm starts to sag after 10 seconds or so.
This along with the fact that the max. rpm keeps increasing with subsequent runs tells me the engine is still tight.

Orv.

Mr Cox 05-23-2011 01:09 AM

RE: Venturi for 061 Wasp
 
They are certainly "ABC technology" but I think it is actually AAN. The cylinder has a hard surface all over and below that it doesn't look like brass to me. The piston is aluminium looking, hopefully with some silicon in it.

They shouldn't need much running in at all. I ran 2oz of 80/20 fuel (full castor and no nitro). Then I've flown it on 702010 all castor for about two years. The piston/cylinder is not too bad, it is the quality of the rest that is a little poor.

If your engine is running too warm I really can't see where it comes from other than a too large prop or wrong compression setting. The crank to case fit is so sloppy that there shouldn't be any extra heat from there. The cox 6x3 are a little too high load, the graupner 6x3 are just about right and the APC 5.7x3 is a better match.
You could add another (and proper) head gasket perhaps and see if that helps. It really should hold a needle setting more or less right from the start.

Another thought, have you checked the internals? The quality on these engines is really poor and you might have something that is not properly fitted, like the conrod for instance.

There is plenty of information on these engines on this forum, just do a search.
They are only a poor copy of the Norvels though and that it is way you don't see much discussion about them here anymore, I guess.

sealdoggy 05-23-2011 11:47 AM

RE: Venturi for 061 Wasp
 
Thanks so much I purchased one this morning, thanks for of the replies

Steve


Quote:

ORIGINAL: uliner

Rsm has them venturi's for AP wasps.

http://www.rsmdistribution.com/index-2.htm


If your engine still tight, check the crank, you may need to polish it a little. Some are thght and take forever to break in.



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