high idle on Hilborn Injection?

bmsracing11 · 3/25/12, 5:50 PM

Picked up used 410 motor this winter, replaced barrel valve,because of being full of old fuel . Checked butterflys all seem tight and closed. Motor runs great ,just cant get it to idle below 2000 rpms???

Tim · 3/25/12, 8:05 PM

Quote:

Originally Posted by bmsracing11

Picked up used 410 motor this winter, replaced barrel valve,because of being full of old fuel . Checked butterflys all seem tight and closed. Motor runs great ,just cant get it to idle below 2000 rpms???

What did you set the leakdown to? Should be around 20-22%. Also, check to make sure you don't have any air leaks (intake gasket leak, air sucking around nozzle opening or nozzle plug). And make sure all of the butterflies are closed. PM me if I can give more help.

Tim Simmons

TQ29m · 3/25/12, 8:33 PM

May not have been "old fuel", might be what was used to keep it from jelling up, so a new one wouldn't have been necessary, anyway, yes, you'll need to ck and set the leakage on it, they don't always come factory set, it might be close, but each is different, and each engine is different, but I'd almost bet you spent money you could have used elsewhere!, and if it was old fuel, and starting to jell, it could have been cleaned, there isn't that much in one, that can't be cleaned. JMHO Bob!

bmsracing11 · 3/25/12, 9:45 PM

Old barrel valve was very pitted. Tried to machine out, but it ran so bad, we swapped it out with one we knew was good. Took off the idle screws, checked linkage all was good. Took car out to run some laps, motor had good pwr but would not idle down. Does this sound like a intake gasket ??

Tim · 3/26/12, 8:16 AM

Quote:

Originally Posted by bmsracing11

Old barrel valve was very pitted. Tried to machine out, but it ran so bad, we swapped it out with one we knew was good. Took off the idle screws, checked linkage all was good. Took car out to run some laps, motor had good pwr but would not idle down. Does this sound like a intake gasket ??

If the leak down is OK I'd say the motor is sucking in air from somewhere.

Tim Simmons

Tony74 · 3/26/12, 8:53 AM

Have you had a timing light on it yet?

If you can get a temp gun on the headers may narrow down which cylinder(s) are lean.

TQ29m · 3/26/12, 1:48 PM

Just FYI, Hilborn has a video on their website, I believe, that walks you thru the shutter alignment proceedure, only takes one, to mess up a good idle. Bob!

6/13/12, 9:04 AM

Could be a air leak, but check other things first. Usually if you have a air leak the rpm will be high but will tend to flucuate, as in move around some. If its a steady high rpm, maybe something else.

3/25/12, 8:33 PM	#3 Re: high idle on Hilborn Injection?
TQ29m Senior Member Join Date: Aug 2008 Posts: 6,262	May not have been "old fuel", might be what was used to keep it from jelling up, so a new one wouldn't have been necessary, anyway, yes, you'll need to ck and set the leakage on it, they don't always come factory set, it might be close, but each is different, and each engine is different, but I'd almost bet you spent money you could have used elsewhere!, and if it was old fuel, and starting to jell, it could have been cleaned, there isn't that much in one, that can't be cleaned. JMHO Bob! __________________ "Being old, isn't half as much fun, as getting there"! Ole Robert I!

3/26/12, 1:48 PM	#7 Re: high idle on Hilborn Injection?
TQ29m Senior Member Join Date: Aug 2008 Posts: 6,262	Just FYI, Hilborn has a video on their website, I believe, that walks you thru the shutter alignment proceedure, only takes one, to mess up a good idle. Bob! __________________ "Being old, isn't half as much fun, as getting there"! Ole Robert I!

3/25/12, 5:50 PM	#1 high idle on Hilborn Injection?
bmsracing11 Member Race Count This Year: 14 Race Count Last Year: 27 Join Date: Feb 2010 Posts: 33	Picked up used 410 motor this winter, replaced barrel valve,because of being full of old fuel . Checked butterflys all seem tight and closed. Motor runs great ,just cant get it to idle below 2000 rpms???

3/26/12, 8:53 AM	#6 Re: high idle on Hilborn Injection?
Tony74 Senior Member Join Date: Jul 2007 Posts: 945	Have you had a timing light on it yet? If you can get a temp gun on the headers may narrow down which cylinder(s) are lean.

6/13/12, 9:04 AM	#8 Re: high idle on Hilborn Injection?
backitin Posts: n/a	Could be a air leak, but check other things first. Usually if you have a air leak the rpm will be high but will tend to flucuate, as in move around some. If its a steady high rpm, maybe something else.