Ok, well Im usually the on giving the adevice on these forums, but this has got me completely stumped. Ive got an OFNA Hyper 7 PCR with a Novarossi T21BF engine. Ill go out run it for 3/4th's of a tank, take it in, check temp, adjust needles if necesary, ect. Then everytime I go to re-start it it will never go. I check the plug and oh, that's my problem... It's dead. I'll replace it with a BRAND NEW SEALED PLUG. Do the same thing bring it back in try to start it, and it won;t go, I'll check the plug, and what do you know... it's dead. I tried again thinking maybe I got a bad plug or somthing. Same exact thing happens bring it back in, it won't sart and the 2nd BRAND NEW plug is dead. It isnt the usual running too lean (it's running perfectly, and temps are right were they should be around 240-250). So I went through 2 brand new plugs and another with only a couple tanks through it. I've been having this problem with this buggy for a long time. THe only thing I can think of is that Im running a medium plug, which should be fine becuase Im using 20% but i guess a cold would be a better choice, still I doubt that's the problem... any suggestions?

i have the same motor in my eight and i havent really had any problems with it yet . my only problem i have and its not really a problem is once i run it same like you. i get it dailed in kill it , it cools down ,then its a little hard to start like it doesnt wanna lite right away , sometimes it wont lite i ll let it sit for a sec then hit it on my box again and she comes to life. other than that she runs like a scalded dog! the only difference is i run a med/cold odonnels plug with 30% tq

maybe the company sent your lhs a batch of bad plugs, and you wer one of the lucky ones to buy them. try a different plug, if it doesnt work, then idk

What brand and blend fuel are you running? Are the plugs dead or are the coils distorted and broke?

it could be 3 things that i know of bad plugs.strecthed rod or maybe the low end is to low.

Well Ive gotta wait to try differnt plugs when i can order them or go to a different LHS until then. How can I checked for a strectched rod, or the other "The low end is too low" what does that mean?

You never did answer my question so I guess you do not want my help! I do not think it is a strecthed rod.

I'm pretty sure he means the lsn is too lean.

Well, thats kind of a wierd way to say it, and no the engine is tuned correctly. I just found what I think is a used (I think barely used) Mcoy MC-9 Plug. I put it in, and I've ran 2 tanks through the buggy without problem starting it 3 times. It might have just been the plug's, but we will see Im gonna try and run some more tommorrow.

Try using two washers on the plugz, I think it makes them cooler

i meant to lean on the bottum just didnt pay attention.

I had the same thing happen on my Hyper 4 port engine...low compression...play in the rod end...OLD engine.
It would run great but after shutting it down the plug wouldn't work any more.
After 3 dead plugs it never did it again...same plug used[sm=confused.gif]