[chevelle1971_350]

Hello, to all
I have Put in A brand new Turn the key zz4 350 in my 1971 chevelle. It is not runnung right the timeing is perfect(checked many times). Put Chevron Supreme gas(4.25 a gallon). I have broken it in like gm said. I step on the gas and i can here the rockers knocking, The idle is really bad I can hear the rockers knocking at idle too. The engine is also miss fireing, its acting like i have a big cam? I had a Freind that works for Chevrolet come over and check it out, and he said he dose not know. So i trun to you guys asking for some help!!!!!!! I know some out there can help me. Thnaks a lot

 

[novaderrik]

for the misfiring thing, the first thing to check is to make sure you don't have the 5 and 7 spark plug wires mixed up at the cap.. if that checks out and it still makes a bunch of noise, then call the GM dealer that you bought it from and ask what you need to do to get it looked at under warranty.

 

[d1_bradley]

When you say "turn the key" do you mean "turn key" as in the carb and fuel pump are on when you got it? Did you adjust the valves before firing? Did you prime the oil pump before firing? Have you checked fuel pressure? Did you set float level? What carb are you using, probably came with a Holley 750.

 

[chevelle1971_350]

Turn key means every thing Fuel pump, holloy 750 carb pretty much everything. I call the man who works for gmpp in turlock and he said i do not need to adjust the valves. And every thing was done befor. I played around with it today and still no luck??????????????????????? I dont no what to do any more i think iam going to call the junk yard next.

 

[novaderrik]

you said the timing is "perfect"- what is "perfect"?
it wouldn't be too hard to see if the line on the balancer lines up with true TDC using a piston stop in the #1 cylinder- it is a mass produced item, and sometimes bad parts make it thru the system.
take out the 4 bolts on each valve cover, and you can take a quick look at the rocker arms to see if one or more of them are loose- i've heard of brand new crate motors with loose rocker arm studs, but those have always been the motors with the fast burn heads on them.

 

[d1_bradley]

Like Derrik says, check it out. I've installed a couple of ZZ4s, one is in my '33. Out of the crate the valve adjustment was WAY off and even though its a roller motor, I did prime the pump. Kind of a habit. These things are mass produced and that means usually all of the parts are there and its close to being right. Of course someone from GM is going to say "its alright", what else would they say? "This is GM and we don't have a clue", don't think so. Anyone who's done this for a while will ALWAYS double check the "tuneup" prior to firing a new engine (float level - valve setting - timing - oil pressure). When hooking up to an existing vehicle you may have dirt in the fuel line, etc. NEVER start a new engine without checking first.

 

[68KMENO]

if you have a noisy valve train I'd start there !!! run through them with the engine off recheck every one.... I know its a pain .... but I have seen BRAND new motors pull pressed in rocker studs Or the people who were assembling them that day ..... were asleep at the switch !!! either way you need to figure it out before you trash something !!!