QuestionKnow anyone that wants to buy a 74 nova? Ok I'm not to that point but close. This frustration comes from the fact that I took all the stuff off the front and changed the timing chain and gears, about a full days work for me and now I have to take it all back apart because my timing chain cover didn't seal up good. Anyway back to your questions and real problems. Yes I meant valve lifters. I adjusted them by feel and sound while car was idling. I said this solved backfiring in my last letter but last time I let the car idle it surprised me with another. Just one nothing like it was. Yes it is like a chuff sound somewhat loud. maybe this can be solved by the timing because I haven't got to setting it to the degrees you spoke of. I did check vacuum hoses. That was easy I only have 2 and no leaks. Explain this combustion test. Is this something I can do because I'm all about eliminating potential problems? Well here it is the question that I don't know if I want the answer to. Do I need to just jerk this engine out and start over on it? This white smoke problem has me worried and I know you question it as well. It just don't seem to fully go away out of that passenger side. Thanks
AnswerWell, if you know someone who speaks Spanish, ask them what NO VA means -that'll give you a hint.
Seriously - don't give up!
I want to review how you adjusted the valve lifters: The right way to do it is to do each lifter adjustment with the engine warmed up and idling at as low an RPM as you can get and not have it stall. If you can't get it to idle smoothly enough to keep your tools on the adjuster, retard the ignition timing temporarily while you do the valve adjustment - this should give you a smoother idle. Don't forget to put it back when you are done. If you aren't sure which way retards the timing, take the distributor cap off and watch the rotor while you crank the engine with the starter. That direction of rotation is the "retard" direction. Move it about 1/2 inch at the edge of the distributor - you will probably have to increase the idle speed adjuster to keep it running that way, but it should be smoother now.
Next, take each valve adjuster and back it off until you hear the clacking start, then tighten the adjustment 1/4 turn at a time until the noise quits, then tighten it an additional 1-1/4 turn, 1/4 of a turn at a time until you have gone the additional 1-1/4 turn. Every time you tighten it 1/4 turn, wait a few seconds until the idle smooths out again before you go the next 1/4 turn - this is very important - if you don't wait, you can bend a push rod or cause other damage. Then go to the next valve and do the same thing, until you have done all 16 of them. If this is what you did, you've got the valves set right.
The test I recommended that you do is called a "Combustion Gases in the Coolant" test. You buy a kit at your local auto parts store - NAPA stocks these or can get it for you in a few hours. I believe theirs is made by Balkamp. Anyway, the instructions come with the kit - it's easy to do: basically, you warm up the engine, then get some of the coolant and put it into the jar they give you that has some special chemicals in it - and watch to see if it changes color. The instructions will tell you exactly how to do it - that is the only way to check for a combustion leak, whether it is caused by a bad head gasket or some more serious problem like a crack in a head or the block - usually it's the head gasket, but not always. The kit is pretty cheap (under $50) and it will last you a lifetime of playing with old cars.
The chuff-chuff sound out the tailpipe is usually because an exhaust valve is burned or set too tight, so be sure to re-check your valve adjustment as I described above.
When you checked for a vacuum leak, did you do it the way I said (by slowly and progressively blocking off the air flow to see if you can increase the idle speed at some partial blocking?).
You mentioned checking vacuum hoses, but there are many other ways you could have a vacuum leak - it isn't always a hose problem!
OK, I'm sitting here waiting to hear it is all fixed now!
Dick
P.S. For some reason, this answer never came back to me from the site (I am supposed to get a copy of it). In case you didn't get it either, here's a second copy. DB
