350 motor keeps going out of time
 

So this has been an on and off problem for me, not frequently but not rarely. I time my engine to 8° and my truck will run fine. 71 GMC c15. And out of random sometimes it acts like the engine is going out of time or like a lack of fuel. It was so bad today I pulled over right away cause it seemed worse than usual. I check the carb, fuel is flowing as it should through the Jets. I check the filter, it's not clogged. I check the fuel sending unit, no blocks. Check all vaccume lines. They are all sealed. Spark plugs and wires are new. Spark plugs we're fine when I started the truck but half way home it started to act up.

I have not checked the timing yet as I just got home but usually the timing is out when this happens. My belt is only driven by the crank, timing and alternator and the belt seems tight. Alternator is mounted as far as possible to offer the most tension. It is a Very belt so I know they can slip when put under heavy acceleration.

Any clue as to solve this problem? I am running out of solutions

Re: 350 motor keeps going out of time
 

The timing gear might be worn. If, you can turn the crank, use the timing mark to see how much play there is in the timing gear, before there is any actual movement in the timing mark itself. Hopefully, I explained that correctly.

Re: 350 motor keeps going out of time
 

Is it possible to change the timing chain and gear while the engine is still in my truck? I've never had timing issues before and all the info I can find is with engines out of the car

Re: 350 motor keeps going out of time
 

You bet you can do it with the engine in the truck. You'll have to remove the water pump, and loosen and drop the oil pan down to get the timing chain cover off. But it can be done.

Gary

Re: 350 motor keeps going out of time
 

I am in need of an oil change and new gaskets anyway so that works out well, kill 3 birds with one stone. Thanks for the info, just checked to see if my timing chain is out and it's pretty sloppy, hopefully she will stay calm if I drive carefully till the parts come in.

Re: 350 motor keeps going out of time
 

If you buy a new timing set, be sure to get a double roller type.