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Engine basics => Engine set up tips => Topic started by: Tom Taylor on July 10, 2008, 10:50:14 AM

Title: K&B 61
Post by: Tom Taylor on July 10, 2008, 10:50:14 AM

I finally started my K&B 61.  It started OK but when I went to open/close the needle valve, I discovered that it was completely closed. ??? When I went to open it, the motor started to lose rpm's.  It was turning about 7800 when completely closed.  I have an Enya needle valve installed.  I am not an engine expert, so any advise would be appreciated. H^^

Thanks,

Tom

Title: Re: K&B 61
Post by: Jim Oliver on July 10, 2008, 11:16:08 AM

Tom,

Sounds like the NV isn't closing off all the way.  Try closing it as far as you can and then check to determine if you can blow a little air through the NVA.  I suspect that you will be able to; if so, you will probably need a different NVA.

The hole(s) in the spraybar also should be very near the center of the venturi, rather than nearer one side or the other.

Cheers,
Jim

Title: Re: K&B 61
Post by: don Burke on July 10, 2008, 11:43:07 AM

Sounds like the body of your NVA is too short for the width of the intake boss on the K&B.  The needle is probably bottoming out on the NVA body before the needle hits the seat.

Randy should be able to fix you up with the correct length NVA.

Title: Re: K&B 61
Post by: phil c on July 11, 2008, 08:10:24 AM

Both the Enya and OS needlevalves use a pressed in needle.  If you cant' get the needle valve to shut off(due to interference with the case) you can press or pull the needle out.  You can also get some metric drill rod from one of the machinery supply houses(Grainger, MSC, etc.) and make a new, longer needle to press into the knurled holder.

Take the needle valve assembly out of the engine and see how far in the needle has to go to shut off flow.  Then you can measure the clearance between the boss on the NVA and the clamping nut to see how much adjustment is needed.

Title: Re: K&B 61
Post by: Tom Taylor on July 24, 2008, 09:04:32 AM

Thanks for the help guys, I took out the needle valve assembly to look it over.  The tube that goes through the venturi has one hole in it.  It is located not centered but maybe a 1/16 of an inch off center.  Reveiwing what Phil was saying sounds like more than I am capabile of doing.  My choices are either machine the housing to install a smaller needle valve or persue a remote NVA.  Looking at the remote needle assmbly I came across this "985-001  K&B Classic Remote needle w/bracket"  What would I use for the nozzle?  Thanks ever so much for the help.

Title: Re: K&B 61
Post by: Leester on July 24, 2008, 12:25:10 PM

If you can't get a factory NVA Save yourself a lot of trouble and call Randy Smith at Aero Products, he'll set you up.

Title: Re: K&B 61
Post by: phil c on July 24, 2008, 01:53:59 PM

Leester, maybe my advice sounded more complicated than it really is.  If the spring is off the NVA, simply close the needle in as far as it will go.  Gently tap the end of the needle with a ballpeen hammer until it moves in slightly.  See if is now closed off.  If not, tap a bit more, until the needle is seated and no air will go through the NVA.  Reinstall and try running it.

With either OS or Enya needle valves it is a good idea to seal the end of the needle to the threaded portion with a drop of solder around the joint to prevent air leaks.