Notices
"1/2 A" & "1/8 A" airplanes These are the small ones...more popular now than ever.

Cox Tee Dee .051

Old 08-25-2015, 07:08 AM
  #1  
jsesere
Senior Member
Thread Starter
My Feedback: (38)
 
Join Date: Apr 2003
Location: Salem Oregon WA
Posts: 259
Likes: 0
Received 0 Likes on 0 Posts
Default Cox Tee Dee .051

What's up with this piston? I've never seen one with a dimple.
Attached Thumbnails Click image for larger version

Name:	003.JPG
Views:	443
Size:	335.0 KB
ID:	2116656  
Old 08-25-2015, 07:14 AM
  #2  
aspeed
 
aspeed's Avatar
 
Join Date: Jul 2011
Location: Ruthven, ON, CANADA
Posts: 3,440
Likes: 0
Received 5 Likes on 5 Posts
Default

It has a lot of wear. It will poke through soon. The ball socket was likely not reset over the years, and/or there was not much oil in the fuel. You can get a replacement still from Cox International. An .049 one is fine too. The .051 piston is a bit heavier, and there is a bit more stress on things.
Old 08-25-2015, 11:19 AM
  #3  
Pond Skipper
 
Pond Skipper's Avatar
 
Join Date: Dec 2009
Location: Texas, TX
Posts: 2,821
Received 6 Likes on 6 Posts
Default

If you get a reset tool you can try a reset and it may flatten the head back allowing you to continue to run the stock piston. I am not sure they carry .051 pistons.
Sometimes they will get in old stock still in the package or will refurbish parts for resale.
Old 08-25-2015, 11:11 PM
  #4  
Mr Cox
 
Mr Cox's Avatar
 
Join Date: Jul 2007
Location: Karlstad, SWEDEN
Posts: 3,791
Likes: 0
Received 1 Like on 1 Post
Default

It might just be a bit poorly machined, in the Estes era anything would go out to customers...

The reset tool should have a recess in the center to allow for these kind of errors, and to avoid deformations to the piston itself.
Old 09-04-2015, 05:51 PM
  #5  
smallrc
 
smallrc's Avatar
 
Join Date: Jan 2003
Location: Elkland, MO
Posts: 84
Likes: 0
Received 0 Likes on 0 Posts
Default

I looked at the full-sized photo - it looks like the ball may be peeking through the top of the piston at this time. If that's the case, it's time for a new piston/rod/cylinder. I had a TD .049 many years ago that did that. I was out of Cox fuel so I went to the lhs and he sold me a jug of 25% racing fuel. He told me "Oh, yeah, it's got plenty of oil". After ruining a TD and a Queen Bee, I checked further and the fuel had 14% oil, mostly synthetic. Lesson learned the hard way - at least 20% oil, at least half of that castor.
Old 09-04-2015, 07:02 PM
  #6  
Pond Skipper
 
Pond Skipper's Avatar
 
Join Date: Dec 2009
Location: Texas, TX
Posts: 2,821
Received 6 Likes on 6 Posts
Default

Yea he posted this on the Cox Engine forum and had discovered it was indeed a hole, the pitfalls of running with out a reset tool.

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off


Thread Tools
Search this Thread

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service - Do Not Sell or Share My Personal Information -

Copyright © 2023 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.