I'm trying to get the timing on the my CJ5 '75 258 set at or near the sweet spot. It seems to lack power and fuel mileage is suffering after I installed a NAPA reman. distributor. Engine does idle and runs smooth. I had it set at 12deg btdc. I backed it down to 9deg. It seems to run better, but I also changed the airfilter before the timing adjustment. The manufacture tag from toledo says 3deg +or- 2. I've also tried to do the pinging test of advancing until a ping under load. I got to 16deg+ and quit. Maybe it's my hearing, but I couldn't get any "ping". My elevation is 8000 feet above sea level. I feel like I'm getting confused with all the adjustments. Please help.
If you're finding it a little sluggish since putting the reman dist in I would start there. The problem is most likely that the rate of advance of either the centrifugal advance or the vacuum advance, or both, is off. They just grab a set of springs out of a barrel and never consider what the original advance curve looked like. Further evidenced by the fact that you can't get it to ping at 16 BTDC. You can attempt to compensate by advancing the timing but it's a pretty poor solution. On some vehicles you could advance a long ways before you got it to ping but would then run into problems with starting when hot, it'll fire against itself as it's cranking and can even crack the starter housing. (that's when you get the sensation that your battery's going dead, cranks, stops, cranks, stops). You used to be able to buy advance curve kits for distributers, consisted of several sets of springs and a different set of weights. You want to get the advance in quite quickly, so go to the lightest set of springs and set the timing to factory spec. Start from there advancing until you can just hear it ping, then back it off until you can just hear it start to ping under extreme load. Slight ping under very heavy load will never damage anything, but you're at the point of maximum efficiency.If you have to retard below factory spec to stop the pinging go to the next stiffest spring. I never used a timing light when doing this,so I can't tell you how far to back it off, besides which you really don't know how many degrees you're "into the ping", so backing it off some pre-determined amount may not be the solution. Steve
" Paul Brogren" wrote in message news:buu795$lo9k0$ snipped-for-privacy@ID-190695.news.uni-berlin.de...
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