Thread Tools
Nov 01, 2021, 05:30 PM
Registered User
I'm not convinced that it's going rich.
Given that the prop is really too big, a common propensity to eschew fuel with 25% nitro plus humidity.....
I would expect that it has varnished itself and it's just sagging rather than getting rich.
Sign up now
to remove ads between posts
Nov 28, 2021, 10:24 PM
Registered User
I think the biggest clue you have is that the engine runs fine with the needle open not even one turn.

If it runs good at three-quarter’s turn I would be curious how it runs at 1/2 a turn and 1 turn.
I would be curious how sensitive the needle valve is. Almost sounds like the one you have might have a blunt end. The correct needle valve is very sharp.
Cute plane by the way. The engine sounds like it’s running very slow for whatever reason. It might benefit from some fresh 35% fuel and a new TD head and gasket. I like the Cox gray competition prop myself. It’s just a little bitty thing and there may be better props but it might be worth a try after you sort out the needle valve problem?
Nov 29, 2021, 07:48 PM
Registered User
A TD head does not exist for a Cox .020
Nov 29, 2021, 09:30 PM
Registered User
At the risk of making a false assumption I have 2 different .020 glow heads? Cox's first .020 was the PeeWee reed valve engine. Later they introduced the TeeDee. 020. The TeeDee .020 head has the serrations around the post on the head, just like the TeeDee .049/.051 heads. The PeeWee heads are smooth around the post? The smooth plugs have a part #1032. I know this because I have some new plugs in their respective packaging. I don't have any of the serrated plugs in Cox packaging, so I don't have a part number for them. My question is did Cox make only one .020 plug with smooth, and serrated tops under the same part #, or did they make a reed valve plug, and a TeeDee plug?
Nov 29, 2021, 10:21 PM
Nitro User
1/2A Nut's Avatar
2 pics showing knurled top .020 glow plugs and later version without .
Last edited by 1/2A Nut; Nov 29, 2021 at 10:45 PM.
Nov 29, 2021, 11:01 PM
Registered User
Quote:
Originally Posted by Greg Doe
At the risk of making a false assumption I have 2 different .020 glow heads? Cox's first .020 was the PeeWee reed valve engine. Later they introduced the TeeDee. 020. The TeeDee .020 head has the serrations around the post on the head, just like the TeeDee .049/.051 heads. The PeeWee heads are smooth around the post? The smooth plugs have a part #1032. I know this because I have some new plugs in their respective packaging. I don't have any of the serrated plugs in Cox packaging, so I don't have a part number for them. My question is did Cox make only one .020 plug with smooth, and serrated tops under the same part #, or did they make a reed valve plug, and a TeeDee plug?
Hi Greg,
Well Iím probably a little older than most here. That being said my old Cox packaging does say for Tee Dee .020 engines. However to be fair I donít recall a head that actually had a different shape chamber than what came on the TD .020.
Sometimes different plugs can have the same part number! My early RR-1 plugs have a part number of 1702 yet are completely different than later TD 049 with that number. I suppose itís possible some 020 heads were made with a slight tulip shaped chamber and some with a larger open hemi shape. I think I remember running into a similar question concerning the Sportsman,Olympics and the mk11 cox 15ís along with the TD 15 and the Special. In the case of the 020 I was only suggesting he try a new head and gasket to improve performance. I donít think it matters much if the package says TD or pee wee. If I had to guess I would say both plugs use the same part number. What ya think ?
Nov 29, 2021, 11:07 PM
Registered User
Quote:
Originally Posted by 1/2A Nut
2 pics showing knurled top .020 glow plugs and later version without .
Well it makes sense to me that they would market them in this manner. Otherwise a person might think they are not getting the right head. Right?
Nov 30, 2021, 12:33 AM
Balsadustus Producerus
Another option might be, looking at the inside top of the glow head. If it looks like a hemispherical shape, it's a low-compression head. If it looks like the open end of a trumpet, just the opposite of the hemi, it's a high compression head. I'd have to look around for some .020's I have to make sure, but that's what memory says, from a 71 year old man...so, a grain of salt...maybe the whole bag...

The knurled top is an indication as well, showing it should be the high compression head.
Latest blog entry: Single Channel Case
Nov 30, 2021, 08:57 AM
Registered User

Glow Head


I find no difference in the two
Nov 30, 2021, 10:01 AM
Registered User
Glow head combustion chamber shape isn't the only thing identical in PeeWee and TeeDee 020 engines.


Quick Reply
Message:

Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
Estes Sky Ranger Pee Wee Flyer conversion Thomas B Scratchbuilt Indoor and Micro Models 34 Jun 10, 2017 04:33 PM
Estes Sky Ranger pee wee flyer nogoer Scratchbuilt Indoor and Micro Models 17 Jan 30, 2017 08:30 PM
Discussion Pee Wee airplanes. Bill Adair 1/2A Planes 2 Jul 03, 2016 01:06 PM
Discussion Cox 020 Pee Wee powered profile balsa Pitts fly_boy_bc 1/2A Planes 1 Dec 11, 2015 01:21 PM
Question Cox Pee Wee .020 Problem? Glue Gun Engines 29 Sep 23, 2011 01:10 AM