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Engine Specific Info and Questions => IDI Engine => Topic started by: jaysen71581 on September 24, 2011, 05:54:38 pm

Title: High Rev'ing
Post by: jaysen71581 on September 24, 2011, 05:54:38 pm

So i have an issue i was running the car today and i went to rev the motor alittle and the damn thing almost tach'ed out so i quickly put it in gear and took off and ran it for alittle while i checked my throttle linkage and its not hanging up anywhere and i had the car running with the hood up and i manually rev'ed it from the pump and the idle shot up really high to the point to where i had to pull the power wire off the IP to stop the motor.  Any ideas?

Title: Re: High Rev'ing
Post by: ORCoaster on September 24, 2011, 06:10:47 pm

This is the exact problem I have with that second IP of mine.  So when you get it figured out let me know.  I think it might be the fuel collar not in the nub of the controller that is connected to the governor or throttle linkage.  Did you have this pump apart for some reason?  

Not the classic runaway as it died when you pulled the power off the solenoid.  Correct?

How far is the max fuel screw turned in?  Might try backing it out a half or more turns and see how it does. 

Title: Re: High Rev'ing
Post by: jaysen71581 on September 24, 2011, 06:18:44 pm

Fuel screw isnt in all the way ill mess around with it tomorrow and take a video for the masses...

Title: Re: High Rev'ing
Post by: ORCoaster on September 24, 2011, 07:23:59 pm

See what happens when you put paint on them.

Title: Re: High Rev'ing
Post by: RabbitJockey on September 24, 2011, 10:14:26 pm

where is your idle?  where is your timing, when i timed by ear before, i had a pump that really drove funky and it would hangand surge at 2500-2800 rpms, it was really weird, once i timed it properly all of that stopped.

Title: Re: High Rev'ing
Post by: DieselBalz on September 25, 2011, 08:27:40 am

Idle screw, turn it back, or turn back your max fuel screw. 10mm for the idle, 13mm for the max few screw and a screw driver.

Title: Re: High Rev'ing
Post by: jaysen71581 on September 27, 2011, 07:32:10 am

I backed down both screws and that seemed to do the trick for now, atleast i couldnt replicate the problem and i made sure to lock them down good...

Title: Re: High Rev'ing
Post by: ORCoaster on September 27, 2011, 08:53:25 am

Good on you,  I know that in order to get my engine to do anything but idle I needed to screw the max fuel screw in.  But then it would take off and not come back down.  Similar but worse than it hanging on the upshift that we sometimes can experience with these pumps.  I think my trouble is more mechanical than the screw adjustment.  Popping the top and looking at how it moves might let me figure it out.  If not I will go back to my other pump and see if I corrected the over pressure problem by repairing the regulator screw.  It was hammered tight together.  Both pins compressing the spring tight and holding it way up in the cylinder hole.

Duh mechanic momment.

Title: Re: High Rev'ing
Post by: jaysen71581 on September 27, 2011, 10:17:54 am

LoL yea i have had plenty of Duh moments on this build..

Title: Re: High Rev'ing
Post by: 8v-of-fury on September 27, 2011, 01:41:27 pm

Duh moments now let you do it flawlessly in half the time later ;) Everyone's gotta learn some way or another.

Title: Re: High Rev'ing
Post by: ORCoaster on September 27, 2011, 06:41:36 pm

Honestly some of my Duh? moments are learners.  Problem is it then takes me twice as long to remember how I ended up doing it right.  So in the end although I do it in half the time I still take forever. 

Well, maybe not that bad.  But it seems that way.  Maybe that is why after 40 years of turning a wrench I really don't care.  It's fun.