midknightc3
SILVER Star
So I actually have questions on both my trucks, as I've never been able to advance my timing beyond 7-10deg BTDC. However, I'm going to avoid questions on the properly running truck at the moment and concentrate on the FJ40 that just suddenly decided to not run right. Quick backstory, I've done this rigamarole previously and thought I had everything sorted after replacing everything in the ignition setup. Engine is (by SN) a 1976 2F with a dented side cover, FJ60 large cap dizzy and Celica igniter. When I installed this setup it fixed some very poor performance issues I had from the previous heavily worn OEM points dizzy out of the F155 that was originally in the truck. Didn't think much of it until last week when my wife barely made it home because the engine kept backfiring and stalling.
Much trouble shooting later, I threw a timing light on it and couldn't find the timing mark. Spun the engine around until TDC compression and theres the mark and rotor is pointed at the #1 plug on the distributor cap (roughly 10 o'clock). Painted the TDC line and BB white, put the gun back on, and I can JUST see the TDC line at the top of the sight window (vac advance is disconnected and tubing plugged, RPM @750). So, I'm estimating maybe 2-4deg AFTER TDC, and dizzy is exactly where I had last set it at full advance (which 9mo ago got me to 10deg BTDC). This explains why she's suddenly running like dookie and backfiring, BUT HOW THE HELL DID THIS HAPPEN? FJ60 dizzy was a rebuilt model from @4Cruisers, along with the ignition module. I'll pull the dizzy tomorrow, but he had put a new gear on it and everything looked beautiful before stabbing it in. Engine was rebuilt by the PO, maybe they reused some internal parts with worn gears? Could they have reused F155 parts in the 2F and that could be the issue?
Hoping this doesn't involve tearing down the engine, but if it's suddenly jumping timing I'm guessing that is where this is headed. Anyone local to central AZ interested in beer for mechanical knowledge in the driveway?
Thanks!
Clark
Edited for clarity
Much trouble shooting later, I threw a timing light on it and couldn't find the timing mark. Spun the engine around until TDC compression and theres the mark and rotor is pointed at the #1 plug on the distributor cap (roughly 10 o'clock). Painted the TDC line and BB white, put the gun back on, and I can JUST see the TDC line at the top of the sight window (vac advance is disconnected and tubing plugged, RPM @750). So, I'm estimating maybe 2-4deg AFTER TDC, and dizzy is exactly where I had last set it at full advance (which 9mo ago got me to 10deg BTDC). This explains why she's suddenly running like dookie and backfiring, BUT HOW THE HELL DID THIS HAPPEN? FJ60 dizzy was a rebuilt model from @4Cruisers, along with the ignition module. I'll pull the dizzy tomorrow, but he had put a new gear on it and everything looked beautiful before stabbing it in. Engine was rebuilt by the PO, maybe they reused some internal parts with worn gears? Could they have reused F155 parts in the 2F and that could be the issue?
Hoping this doesn't involve tearing down the engine, but if it's suddenly jumping timing I'm guessing that is where this is headed. Anyone local to central AZ interested in beer for mechanical knowledge in the driveway?
Thanks!
Clark
Edited for clarity
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