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In gear and driving... '58 BN4 But Dieseling...

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ronzet

ronzet

Jedi Knight
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Hey guys and ladies....

The Healey was driven today for the first time since 1973.... Well, at least back and forth in the driveway!!!

However... As you may recall this is a FULL frame-off... The engine and carbs were also completely rebuilt...

Problem is that I am experiencing significant dieseling when I shut the engine off...

I can do the ol' hands over the carbs trick and it shuts off....

I suspect the carb adjustment... BUT, looking for suggestions.. /ubbthreads/images/graemlins/rolleyes.gif

Oil pressure is good at 35-40 psi warmed up and the water temp is 190....

This was REALLY COOL... to use the venacular...

/ubbthreads/images/graemlins/driving.gif
 
HI Ronzet. usually a combination of things will reduce the tendency of the engine to run on: 1] reduce the Idle speed. 2]richen the carbs slightly. 3] vary the engine timing a bit. 4]Reduce engine runing temperature. However, Until the run on can be cured/reduced,place the gearbox in third gear and ease out on the clutch after shutting the engine off.---Fwiw--Keoke
 
Re: In gear and driving... '58 BN4 But Dieseling.

Gentlemen,

Good morning... Thanks for the suggestions.. I will check them out...
 
Re: In gear and driving... '58 BN4 But Dieseling.

91 octane is right on the edge for my BT7.

When in Canada I used 94 and had no run-on after shutting off the ignition.

FWIW
 
Re: In gear and driving... '58 BN4 But Dieseling.

bighly,

I am running 91 octane. At least I think so. I sent my business partner down to the gas station to get of few gallons in a jerry can.... I will ask him what he got, BUT for the little that I have run this; just firing up, tuning, and a couple of short back and forths in the driveway, is it in your experience that the run-on would occur???

I 'preciate your comment...
 
Re: In gear and driving... '58 BN4 But Dieseling.

Maybe when you get more miles on it will settle down, but another trick is to hit the gas just as or very slightly after you switch off. Since the SUs have no acc pump, it will not put more gas into the system and it will break the vacuum that draws gas through the carbs to create the run-on.
 
Re: In gear and driving... '58 BN4 But Dieseling.

artmck,

Thanks.... hopefully a timing adjustment will resolve the issue... in the interim.... hitting the gas will fit the bill...
 
Re: In gear and driving... '58 BN4 But Dieseling.

No real substitute for higher octane. The additives "octane boost" don't really do much according to my chemical engineer friend working for a refinery. Timing adjustments will help some though as others have pointed out. I use the release the clutch method sometimes.
 
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