Rocker arm play

[Cags70PolaraConvert]

So last week was battery terminal and getting her started, which has been done. One pump of the pedal and turn the key and she is running. Problems now are:

1) Loud tick from the under the driver side valve cover
2) although she idles nicely when I step on the gas she dies out.

I took off the valve cover and the four rockers to the back of the motor on the driver side have a lot of side to side play. The others didn't move at all. Could that just have been due to the positioning of the cam on the lifters at the point I looked at it? Anything I can check?

Going to pull the plugs this weekend to take a gander that nothing is mucked up. Its been years since new plugs but they have minimal mileage on them. Any other thoughts?

 

[Davea Lux]

So last week was battery terminal and getting her started, which has been done. One pump of the pedal and turn the key and she is running. Problems now are:

1) Loud tick from the under the driver side valve cover
2) although she idles nicely when I step on the gas she dies out.

I took off the valve cover and the four rockers to the back of the motor on the driver side have a lot of side to side play. The others didn't move at all. Could that just have been due to the positioning of the cam on the lifters at the point I looked at it? Anything I can check?

Going to pull the plugs this weekend to take a gander that nothing is mucked up. Its been years since new plugs but they have minimal mileage on them. Any other thoughts?

The side play on Mopar rockers will not usually cause problems as this style rocker is designed to float on the shaft. If you have clicking, start the engine and use a feel gauge to see which rocker is clicking, check that push rod to be sure it is not bent. If the engine idles normally, but dies on depressing the throttle, that is usually an indication of a bad accelerator pump in the carb. Ethanol bled fuels destroy the leather pump membrane and the accelerator pump stops working. Remove the air cleaner with the engine off and pump the throttle. You should get a good squirt of gas in the carb bore, if you do not, the accelerator pump has likely failed.

Dave

 

[Cags70PolaraConvert]

That is what happens. Off idle if I hit the gas she dies out unless I can get her past that zone, then she roars. this is in park of course. When I drove her around the block on Saturday she died out on me trying to give her gas. Basically made it back at idle.
Let me say that I am not a mechanic so not sure how I would use a feeler gauge around the rocker issue. I know enough to do some basics, maybe a little more than basic, but I don't have many car specific tools. With that being said is changing out the accelerator pump or rebuilding the carb something a person with limited car repair experience can do(righty tighty lefty loosey.? I've personally done the fuel pump, fuel line, new gas tank, can change spark plugs. Replaced the tubing on the convertible top. But when I had the intake and carb put on the car I had my mechanic do that.

 

[Davea Lux]

That is what happens. Off idle if I hit the gas she dies out unless I can get her past that zone, then she roars. this is in park of course. When I drove her around the block on Saturday she died out on me trying to give her gas. Basically made it back at idle.
Let me say that I am not a mechanic so not sure how I would use a feeler gauge around the rocker issue. I know enough to do some basics, maybe a little more than basic, but I don't have many car specific tools. With that being said is changing out the accelerator pump or rebuilding the carb something a person with limited car repair experience can do(righty tighty lefty loosey.? I've personally done the fuel pump, fuel line, new gas tank, can change spark plugs. Replaced the tubing on the convertible top. But when I had the intake and carb put on the car I had my mechanic do that.

A feeler gauge is a valve adjusting tool that can be bought at any auto parts for about $10. It is a series of thin blades in different widths. You insert one of the thin blades between the rocker and the top of the valve stem, if it goes in freely, the lifter on that rocker is collapsed and will be the source of the click. (Do this with the engine running) Having identified which one is loose, turn off the engine and spin the push rod to see if it has a wobble, if so it is bent and should be replaced. On engines that sit for years, valve guides rust up and the push rod can get bent trying to free up the valve.

Dave

 

[Cags70PolaraConvert]

thanks for the details. Got it.

 

[mopar440]

A feeler gauge is a valve adjusting tool that can be bought at any auto parts for about $10. It is a series of thin blades in different widths. You insert one of the thin blades between the rocker and the top of the valve stem, if it goes in freely, the lifter on that rocker is collapsed and will be the source of the click. (Do this with the engine running) Having identified which one is loose, turn off the engine and spin the push rod to see if it has a wobble, if so it is bent and should be replaced. On engines that sit for years, valve guides rust up and the push rod can get bent trying to free up the valve.

Dave

Doesn't oil squirt all over while running?

 

[Davea Lux]

Doesn't oil squirt all over while running?

Yes, but that is the only way to tell which lifters are not pumping up because they will all leak down with the engine shut off.

Dave

 

[mopar440]

Yes, but that is the only way to tell which lifters are not pumping up because they will all leak down with the engine shut off.

Dave

I might have to do this, how bad is the oil squirting?

 

[Davea Lux]

I might have to do this, how bad is the oil squirting?

It will be mostly leakage off the rockers as they go up and down, it will not generate huge amounts of splash at low rpms.

Dave

 

[3175375]

I might have to do this, how bad is the oil squirting?

Like others have said, it won’t be too bad. In Corvairs, we sacrificed a valve cover and cut a big hole in it. We then adjusted the rockers when the engine was warm, to guarantee that we had them adjusted the rockers perfectly for each valve.

 

[detmatt]

It will be mostly leakage off the rockers as they go up and down, it will not generate huge amounts of splash at low rpms.

Dave

Lay an absorbent rag across the top of the exhaust manifold and tuck it down as far as you can where the manifold meets the head. This will keep oil on the manifolds to a minimum.
what I’ve done to make this same determination is make yourself a diagram of the valves on a piece of paper, run the engine for a minute or 2, pull the valve covers and the number 1 plug and with the key off turn the #1 cylinder to TDC on a compression stroke. At that point you’ll see both valves on that cylinder will be closed as will 6 others on the engine. Those rockers will all be loose and the other 8 you should not be able to move with your fingers, mark the ones you can’t move on your diagram. Then rotate the engine 180 so that #6 is at TDC on compression stroke so both valves closed and the other 8 rockers should be too tight to get movement on with your fingers. Mark those on your diagram and if all of the lifters managed to stay pumped up in the short amount of time it took to do this since the first step of running the engine there should be no blanks on your diagram. If there are, those may be your noisy collapsed lifter or bent pushrod etc..

 

[65Fury440]

You can also use a length of rubber hose as a stethoscope to hear where the noise is coming from, or even a long screwdriver. You may even be able to use a hammer handle to push each rocker down on the pivot point to see which one changes pitch while it's running. You should be able to isolate it pretty quick.

 

[bluefury361]

I've checked for a noisy rocker by light pressure with the palm of my hand on the pushrod side of the rocker while running. A little pressure and the noisy rocker will quiet down.

 

[furious70]

To the uninitiated the hose as ears trick sounds funny but it works, mess free way to narrow it down to a couple before getting messy