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AC439
01-31-2009, 04:17 PM
I think I'd better off start a new thread from my original "No more ordering from rockauto" regarding the vacuum advance issue.

So, I have the carb vacuum advance from rockauto installed on my 86 LXi. The vac advance fits directly but the two hose connections are pointing toward the thermostat housing. I've got new hoses and didn't get the elbow. The clearance are tight but the hoses do not kink at all. The reason I didn't get the elbow is there is more opportunities for leakage when more connecting parts are involved.

I adjusted the linkage on the vac advance to the same length (maybe 1/2 turn longer) as the original broken adv. First driving impression was getting a little low end torque back. The idle speed is about 100rpm lower then usual so I think the linkage needs to be shorten about 1/2 a turn and I think it will be close enough. However, my fast idle valve was dirty (have some idling issues) and definitely not giving me a good impression about how well the new vac advance works.

I took off the fast idle valve from the car and disassembling everything apart. Definitely it was dirty inside. The big adjusting screw was kind of stuck and I was unable to turn much. I sprayed brake part cleaner to remove dirt, then I was able to unscrew it completely and took apart the internal parts. Got everything clean, put back to the car and my cold engine fast idle was down to around 1800 from 2100 first start and then dropped to 1500 after 10-15 seconds. This is much gently putting in gear during cold start.

I have to drive the car more and will post more report after I "fine tune" the length on the vac advance linkage.

-AC

2oodoor
01-31-2009, 05:41 PM
your vac adv is adjustable?
you may want to spray some lube in the bottom of the dizzy where the centrifugal advance wieghts are so you get full total advance at cruise rpm. Those tend to get stiff and or stuck after 20 years.

AC439
02-01-2009, 04:42 AM
your vac adv is adjustable?
you may want to spray some lube in the bottom of the dizzy where the centrifugal advance wieghts are so you get full total advance at cruise rpm. Those tend to get stiff and or stuck after 20 years.

I have already done the "Lazy man's dis rebuilt". The vac advance's linkage shaft is like a screw and has threads on it. You can rotate it to adjust the length. The old one was rusted but the new one can be rotated.