Help with 77 Spider

[REHolder]

Owned the car for 1 year. Problem has slowly progressed. When car is cold, engine runs and sounds fine. After warm up, noise that sounds like valve chatter or pinging occurs any time you load the engine. I have fiddled with the timing to no success. Choke is working properly. With air cleaner off, noise seems to be coming thru the carb. Please help. Someone said engine may be starved for fuel, could high speed jet be the problem?

Thanks,

Robert

[RRoller123]

Check VALVE timing. With NUMBER 4 piston (next to firewall),On COMPRESSION stroke.

[18Fiatsandcounting]

I'd also check the valve clearances. And, if you haven't already done this, I'd change the oil, perhaps even trying something like 20W-50. Older Fiats can clatter as they warm up, and sometimes thicker oil helps. It's not a long term solution, but it might help point you to what the problem is.

-Bryan

[REHolder]

How do you check valve timing for one cylinder, I thought timing is either correct or not for all 4 cylinders?

[18Fiatsandcounting]

How do you check valve timing for one cylinder, I thought timing is either correct or not for all 4 cylinders?

The easiest way to check valve timing is to turn the engine by hand until the #4 cylinder is exactly at TDC and its spark plug is ready to fire (distributor rotor pointing towards the #4 plug wire on the distributor cap). At that point, you should be able to see two small holes in each camshaft pulley, a little more than half way out from the center to the outer circumference, and these holes should be pointing directly at the timing bracket pointers (if you have these), or directly next to two raised bosses on the front end of each camshaft box housing.

Hope that made sense...

-Bryan

[REHolder]

SO are you saying that the timing belt may have jumped on the splined camshaft pulley pulley? Or, is there an adjustment you can make underneath the cam timing cover?

[RRoller123]

Yes, as per the diagram I posted below.