Timing Way Off But Don't Know Why
XinnKoda
Jeeper
I'm helping my dad restore his 1971 CJ5 with the Dauntless Buick 225 V6 v6. We replaced all the normal stuff you'd get in a tune up kit but we can't get it to start now. It ran rough before so I wanted to check the timing. I noticed the previous owner had all the spark plug wires in the incorrect spots on the dizzy. (I.e. cylinder 6 was actually labeled cylinder 1, etc.). I didn't pay attention to whether it followed a certain pattern so I just plugged them in according to the 165432 firing order. I verified TDC with the #1 piston and the timing marks on the harmonic appeared to be accurate. I set timing to 5 degrees BTC but every time we try to start it, it backfires with a loud bang from the exhaust. I continued advancing the timing until it backfired from both the exhaust and the carb (didn't realize this was possible). I manually pulled the dizzy cap and checked to see that the rotor was pointed at the #1 cylinder and I checked to make sure #1 cylinder is TDC. I double checked my wires and ensured they are all going to the proper cylinders but my gut tells me with it backfiring through both and intake and exhaust, the firing order is incorrect. I think my next step will be to pull all the spark plugs and manually rotate the crank and check all cylinders to verify the firing order is in fact 165432. After that I'm really not sure. It's an odd firing engine if that makes any difference. I've never timed an odd firing engine but I didn't think it would be any different than even firing engines. If anyone has any suggestions on what might be going on it would be appreciated!