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A blown power valve will usually exhibit black smoke out the exhaust from the mega-rich mixture. I'm still betting on an ignition issue.
You may be right but I personally suspect a valve train issue (spring/valve seat/pushrod/rocker arm or lifter) but I may be wrong.. 2nd place in my opinion could be head gasket issue.. I highly doubt that it's a bottom end issue as there was no smoke at all and no issue with oil pressure..
If it's the bottom end and I have to pull the engine, I'll likely drop in the 406/600 HP engine that I've sitting in my garage.. I would have to change pistons on it to drop compression to allow pump gas in it... Right now, that engine has 13.5:1 compression..
see pic below..
Last edited by GrandSportC3; Nov 7, 2017 at 01:52 PM.
Start with the easy to check stuff first before you do major surgery. The problem started abruptly, so something broke, wore out or fell out of place. If you are lucky it will be an inexpensive part and easy to fix. Good luck.
Start with the easy to check stuff first before you do major surgery. The problem started abruptly, so something broke, wore out or fell out of place. If you are lucky it will be an inexpensive part and easy to fix. Good luck.
Pulled off the valve covers and checked the lash on the valves.. No obvious valve train issues.. everything is tight with no signs of any issues.. Had a hard time getting off the valve covers.. They were stuck pretty good to the cork gasket and the cork gasket is stuck pretty good onto the heads..
Will pull the plugs tomorrow.. Couldn't find the proper 13/16 wrench for the spark plugs right now, so I will have to do it on another day..
Last edited by GrandSportC3; Nov 7, 2017 at 07:37 PM.
Finally, I had time to do some more research on my issue.. Turned out to be a carb issue.. The carb had so many issues that I had to have it rebuilt.. Car runs better than ever before now.. Haven't driven the '68 since November.. Glad to finally got her back running..
Last edited by GrandSportC3; Feb 16, 2018 at 03:39 PM.