Re: Miss at Idle

Posted by DrewLA On 2013/3/5 16:44:45

Yes, I should have mentioned I did a full tune-up (minus cleaning the fuel bowl since the fuel pump was just replaced a year ago).

In addition to what I mentioned already, I:
-Set idle at 375 rpm in high with the parking brake set, per specs
-Tightened manifold bolts to 27 ft. lbs.
-Tightened carburetor flange
-Adjusted idle using a vacuum gauge to obtain smooth idle - the highest and smoothest it gets registers 16 in. Hg. on the vacuum gauge. And sometimes it's very smooth
-Re-torqued cylinder head bolts (I did this two months ago right before I painted the block)

Things I haven't done because I don't have the proper tools, don't know how to do them safely, or have wanted to eliminate other things first:
-Cylinder balance test
-Exhaust gas analysis
-Remove valve cover and inspect valve springs (no reason to suspect broken springs given that I would have trouble at higher RPM as well)
-Rebuild carburetor (I have a spare I want to test but it needs to be rebuilt first, i.e., I don't want to rebuild the one that I'm using now since I know it to be functional -- I'd rather have a known functional and a fresh rebuild to test with in case I bungle the rebuild).