Re: FJ Vacuum Advance "Boost"

[rhundley]

Okay maybe I am barking up the wrong tree here...I want to disconnect the boost vacuum line because I am under the assumption that is what causes the rpm boost in second gear? Feels similar to the power band? I don't like it because it is not smooth at all! When I the boost kicks in it cuts in and out like, (here are my engine sounds) vroom vrroom vrrrooomm. Sorry....
Is this not from the boost??
It makes it hard to power out of a corner when I can't rely on the performance of my bike.

[racerrad8]

If it only does it in second gear then, I bet you a buck the transmission is jumping in & out of 2nd gear...

The dreaded 2nd gear issue associated with a lot of the early FJ's.

Since you say it is not smooth, that also tells me it just jumping the drive cogs of 2nd gear.

If you want to unhook the vacuum booster, go ahead, just plug the vacuum line before riding. That will tell you if that is the problem.

Randy - RPM

[Pat Conlon]

Well, I hope I was clear I my explanation (in the Files) but that's ok, see for your self....here's what to do:

Disconnect and plug the vacuum line....does it make a vroom difference? Any difference?

With it disconnected, when you close the throttle the ignition no longer advances you will notice that you slow down quicker from the engine compression....
.....but that sound is RRrrrrrrrrrrrr, not the vroom vrrooom vrrrroooommm sound

[FJmonkey]

My 86 has the dreaded 2nd gear issue, just like a rev-limiter, stop hitting it. It will get worse, mine kicks in around 6/7K, so I short shift into third... When I can afford the fix I will get the dogs fixed (under cut) and some other good stuff done to my FJ by Randy at RPM....