4.9L ticking noise
 

My 1980 4.9L carbed engine makes an intermittent ticking noise, more so when it's warm/hot. Bear with me its like: tick tick tick tick pause tick pause tick tick tick tick tick tick pause tick tick etc. Is this a lifter problem?

It very well could be. When the oil is cold, it's thicker, and oil in the lifters takes more to compress (thus no tick). Once it warms, the oil is thinner and allows them to compress easier and tick.

You could try a jug of Marvel's Mystery Oil during your next oil change to see if that might free it up and get rid of it.


However, before you do that, double check that it isn't your PCV valve that isn't making the noise on the back end of the valve cover. They'll make some noise when they go out and are only a couple bucks to replace.

Thanks for the information. I did replace the PCV valve last summer so I will check it again and try the oil. They may carry it here at Walmart or a similar product like Rislone.

A quick test is to just pinch the vacuum line going to the PCV with a wrench to pinch off the vacuum.

Yeah, Marvel Mystery Oil is really popular, so you shouldn't have any difficulty finding it. :)

Also, a 1980 would have the stock log manifolds and the exhaust pipe connects to the manifold and there is a gasket (donut) between them. When the donut burns out, one can get a ticking noise.

Thanks for that. I think I did hear once that the exhaust could make that noise so I'll definitely check that out once Spring arrives.

another thing to check are your rockers...and everything under them. i have come across more than a few mistreated engines that have old oil and gunk that has built up over time. some had bent pushrods, others with clogged pushrods, dead lifters, and loose rockers. once you flush it out and its still giving you a headache...might be a good idea to dig into the valvetrain a bit. feel free to PM me with any questions.

Yeah, that's next if it doesn't clear up. The engine was a newer (rebuilt) one when I bought the truck a few about 12 years ago and this started about 4 years ago . The truck is driven infrequently for about 5 warm months a year with oil change after every season.

I just find it strange that it gets worse as it gets warmer. Generally, all exhaust noise issues I've had are the opposite. The metals expand with heat and help to seal the leak, reducing noise. I also wouldn't think exhaust, lifters, valves, etc. would be intermittent.

However, changing out the donut is easy (the only difficulty associated is determined by how rusted in place the exhaust bolts are) and cheap. The donuts are about $5 or so.

One good thing to have hanging on the wall in the garage is either a good mechanics stethescope, or even a few feet of garden hose. listen around the engine bay at various locations on the block, around the covers, etc. to help eliminate potential sources of the noise. it may not help you determine exactly whats going on, but it'll get you pretty close.

Good advice. Just got to wait for Spring to arrive now.

does it have the flapper in the exhaust manifold? I have heard of the spring breaking allowing it to flap. Just something to check.

I'm not familiar with that. Where do I look?

I'll check but I can't say I've seen this. I assume this is just before the donut; if so, is it just the spring that needs replacing?