At 07:52 AM 8/8/2005 -0400, Greg Rowe wrote:
>I'm having trouble with the vacuum advance on my 1978 US spitfire with
>the stock Lucas 45D4 distributor with an Allison Electronic Ignition.
>But when I disconnect the vacuum advance, the problem goes away.
>It seems to me that the timing is "jumping" when the vacuum advance unit
>comes into play and I can't figure out why. Initially the vacuum unit
>was mounted loose on the distributor but I have tightened it down and
>that made no improvement. I have also checked for a vacuum leak in the
>hose and carb fitting by the rather low tech method of sucking on the
>line, the distributor advances smoothly and stays in place.
Greg,
The only thing I can think of with the 2 problems that you fixed, they
were masking this problem.
Is it possible that the dist. shaft bushings are bad, allowing the
rotor button to move in relation to the dist cap. Wouldn't that in effect
be changing the timing?
Does the 78 have the hall effect or optical pick up? I've heard that the
electronic points (either hall or optical) aren't as suseptable to the
bushing wear as points are.
John
John T. Blair WA4OHZ email: jblair1948@cox.net
Va. Beach, Va (eBay id: zebra48-1)
Phone: (757) 495-8229
48 TR1800 48 #4 Midget 65 Morgan 4/4 Series V (B1109)
75 Bricklin SV1 (#0887) 77 Spitfire 71 Saab Sonett III
65 Rambler Classic
Morgan: www.team.net/www/morgan
Bricklin: www.bricklin.org
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