Spark Plug Heat ranges?  
View related threads: (in this forum | in all forums)

Tower Hobbies
Enter up to 4 keywords or Tower stock numbers
Logged in as Guest



Users viewing this topic: none
  Printable Version
       

All Forums >> Glow Engines, Gas Engines, Fuel & Mfg Support Forums >> Engine Conversions >> Spark Plug Heat ranges?
Page: [1]

Login
Message << Older Topic   Newer Topic >>
Spark Plug Heat ranges? - 7/21/2008 10:19:09 PM   
JIMARRINGTON


 

Posts: 563
Joined: 8/17/2004
From: NEW BOSTON, TX, USA
Status: offline 		How do the heat ranges affect our conversion motors. For example, I have a Ryobi that I converted that had a Champion DJ7J in it. Got a lot of interference and the motor likes to stall sometimes if come down to idle too fast. I have just ordered some Champion RDJ8J plugs for it. This is one step hotter and has a resistor that I hope will stop the interference. What is the opinion of the experts here on the hotter plug?

Thanks
Jim
       Post #: 1

RE: Spark Plug Heat ranges? - 7/21/2008 11:55:29 PM   
T.L.A.R. eng


 

Posts: 80
Joined: 1/2/2008
From: henry, IL, USA
Status: online 		The heat range really depends on how you are using the engine. The stock DJ7J plug is for weed eat'in or what not. It is intentionally colder to prevent the weed eater from dying before it gets out of warranty in case some one uses it in rather extreme conditions.
If you are going to fly the conversion, it could stand to have a hotter plug. The engine will potentially see more cooling traveling through the air. Depending of course on how the engine is cowled. The Champion RJ-8 is a step in the right direction.
The resistor should help curb radio interference from the ignition system.
If you use the two needle carb, you can tune the engine to run just about perfect through all the rpm ranges. They transition better than the single needle carb and definately worth upgrading.
Gary

(in reply to JIMARRINGTON)
       Post #: 2

RE: Spark Plug Heat ranges? - 7/22/2008 12:29:49 AM   
pe reivers



Posts: 2618
Joined: 1/23/2002
From: Arcen, , NETHERLANDS
Status: offline
quote:

ORIGINAL: JIMARRINGTON

How do the heat ranges affect our conversion motors. For example, I have a Ryobi that I converted that had a Champion DJ7J in it. Got a lot of interference and the motor likes to stall sometimes if come down to idle too fast. I have just ordered some Champion RDJ8J plugs for it. This is one step hotter and has a resistor that I hope will stop the interference. What is the opinion of the experts here on the hotter plug?

Thanks
Jim

First of all, stay within the heat range that the engine was designed for. For interference suppression (nothing to do with heat range) Change to R-type plugs. Some ignitions need the R-plugs, whilst some abhor them. You need to find out by trying, or something as simple as a phone call.
Most engines have a patent pending on the ignition system. Go to http://www.uspto.gov and find the patent that describes the system you have. Loads of information there.

< Message edited by pe reivers -- 7/22/2008 12:31:27 AM >

_____________________________

Pe, Dealer for MVVS, MTW and Mejzlik; www.mvvs.nl
There is sanctuary in analisys.

(in reply to JIMARRINGTON)
       Post #: 3

RE: Spark Plug Heat ranges? - 7/22/2008 2:31:48 PM   
JIMARRINGTON


 

Posts: 563
Joined: 8/17/2004
From: NEW BOSTON, TX, USA
Status: offline 		Thanks for the info guys. Last night I went through my stack of motors to see what heat range plugs were in them. I have a pile that a local repair shop gives me every so often. My pile was about evenly split between 7 and 8 heat range plugs. I think I will go ahead and try the 8. As a matter of fact, my local supplier dropped off another 5 engines last night. Had to tell him that I now have enough weedies to last a while but to keep a look out for some larger chain saw motors. Probably got somewhere around 20 free weedeater motors now. Mixed lot of Poulans, Ryobis, and Homelites.


Jim

(in reply to pe reivers)
       Post #: 4

Page:   [1]
All Forums >> Glow Engines, Gas Engines, Fuel & Mfg Support Forums >> Engine Conversions >> Spark Plug Heat ranges?
Page: [1]





Jump to:


Google 



Search | Marketplace | Event Calendar | Local Clubs | Magazine | Product Ratings | New Products | Discussion Forums

Photo Gallery | Member Video Posts | RCU Video Gallery | Instructor Search | Field|Track|Marina Search

Advertisers | Hobby Vendor Resources | Rate Manufacturers | Sign In/Sign Up

SITE MAP!   : :   FORUM RULES

© 2001 - 2007 24-7 RC, LLC, all rights reserved.

Charities we support that also need your help
Yorkie Rescue | Humane Society | ASPCA | Crohn's-Colitis America

Kaango.com Classifieds

0.797RCU1