Topic: Vanny running rough

[coon B14]

when adding kill switch did u leave the diodes in place? they make it so the coil doesnt back feed the other coil when fireing witch will give u a back fire or week spark this is the diodes for it if u dont have them http://eccarburetors.com/webstore/wire-assembly.html

[msnookums]

I've actually run it without the kill wires connected at all, just to see. No difference.

[coon B14]

Can take a video of u running the engine so we can her what it sounds like

[msnookums]

Sure can. I might be able to do it tonight.

[msnookums]

Here is the link for the video... It was taken with my phone so its a little crappy... This is with the #89 main jet, so it actually smooths out at higher rpm. I'm not revving it too high here, I don't have the governor adjusted for higher speed yet. Also the header has been taken off for final welding, so it's just open ports right now.

http://www.flickr.com/photos/97873389@N08/9095396357/

[ARC C63]

You need exhaust and the mower Hot to get a good read and flicking the throttle is not good ez up the rmps

Ps it looks like rich seeing the flames coming out

[carolinablue]

Matt have you been testing all along with no headers on.  You need to have headers on.

[coon B14]

u do need headers it will runn crappy with out and with the cam and everything u have done it wont idle where u were trying to idle it idle with that work is around 1500 and wakes up around 5000 for a governed class u probly need to put stock cam in or run an ungovered class

[msnookums]

I haven't been testing without headers. I just took them off before the video to finish welding. (It's a chrome stack out of the top) to me it ran no different with vs without the stack. I feel I finally got it better up top, but throttle response is terrible. I know flicking the throttle isn't really a good way to show you guys how it runs, I was just trying to show its bad response. The stock motor with over a 1000 hours had better throttle response. Or should I not expect good response until higher rpm because of the cam? I'm starting to think the cam is too big now. (I know nothing about cams in these engines, I took hodges recommendation.) I could tell you how a small block Chevy would run with various cams but not a Briggs motor. I could advance the cam a tooth and see what happens.

[msnookums]

Sorry to kick up an old post, but I wanted to update you all on this rough running vanny. Thanks to all who steered me in the carb direction.
I ended up getting the solenoid hole in the carb welded and tapped it to install the adjustable main jet parts from the briggs updraft flo-jet carb. I had to put a slightly smaller low speed jet in it and I was able to tune it and make it run like it should. This thing really runs good now. Now... I'm considering getting the heads shaved a bit.

[carolinablue]

Thank's for update!  I didn't realize you still had the solenoid in there

[msnookums]

The solenoid actually hasn't been in there for a while... I've never liked those things anyway. Just didn't know what else to call the hole. Needless to say it's got an adjustment needle in there now.