Economical replacement rocker arm set?

-
I was able to get a good recording of the tick. I tried the screwdriver method without luck. It's definitely coming from the 5/7 area. I can also hear it below 1200.

I'm wondering if I should try an engine oil system flush after I have the pan gasket replaced.

 
Could be a rocker hitting under the valve cover, a push rod banging around in the guide hole, or even something lose back in the clutch area. As well as something loose/worn in the valve train. It sounds to have too much of a sharp metallic character to it to be an exhaust leak at one exhaust port, but those often sound very similar to a valvetrain tap.

Have you pulled the valve cover yet?
 
nm9stheham said:
Could be a rocker hitting under the valve cover, a push rod banging around in the guide hole, or even something lose back in the clutch area. As well as something loose/worn in the valve train. It sounds to have too much of a sharp metallic character to it to be an exhaust leak at one exhaust port, but those often sound very similar to a valvetrain tap.

Have you pulled the valve cover yet?
Click to expand...
No, :(. Been busy. I have some time right now. I will warm it up, pull the cover and see if I can depress the rod.
 
nm9stheham said:
Could be a rocker hitting under the valve cover, a push rod banging around in the guide hole, or even something lose back in the clutch area. As well as something loose/worn in the valve train. It sounds to have too much of a sharp metallic character to it to be an exhaust leak at one exhaust port, but those often sound very similar to a valvetrain tap.

Have you pulled the valve cover yet?
Click to expand...
And just to confirm, I hand crank the engine till I see the rocker raise then lower which would put the rod on the heel side of the lobe? Continue on for each rod I want to check?
 
OK, well when you depress the pushrods to see if you have a weak lifter check valve, you have to first rotate the crank as you check each one so that each valve is all the way down. If the valve is lifted, then the cam lift will take all the slack out and you won't be able to tell.

The easiest way to do this is to rotate the crank to TDC, look under the cap to see if #1 or #6 is firing, and then test that cylinder's pushrod pair. Then rotate the crank 90 degrees, and check the pushrod pair for the next cylinder in the firing order. And on and on....

Which is similar to what you wrote a bit ago and I just now read....
 
And what you are looking for is for a pushrod to push straight down into a lifter and be soft. Not that they will slide side to side.

The rockers at least look correctly ordered.

Have you check torque on each rocker shaft bolt to make sure they are all at 15-18 ft lbs?

OK on no baffles.
 
nm9stheham said:
And what you are looking for is for a pushrod to push straight down into a lifter and be soft. Not that they will slide side to side.

The rockers at least look correctly ordered.

Have you check torque on each rocker shaft bolt to make sure they are all at 15-18 ft lbs?

OK on no baffles.
Click to expand...
I was just thinking I should check the torque of the bolts.

I wanted to see what the soft lifter would feel like first so I just tired pushing all of them on the drivers side. None would budge. I even grabbed a sock and extension to get move leverage on them and still no movement. How much pressure does it take to push on them?
 
If the check valve is weak, you'll know from pushing with your hand. If it is holding, it won't budge.

But follow the procedure I outlined to make sure the lifter is on the heel of the lobe.
 
This is maddening. I have rotated it and checked 5 and 7 so far. Still no movement. I will check the rest.

My stroke on the cranknis only about 10-15 degrees each slow stroke. Ugh.

I'm not seeing the rockers move up and down. Did I lose my oil in the lifters already?
 
Yes, understood on the shot crank movement.... tiring. Are all the rockers not moving? Or just 5 & 7? They WILL move, even with oil loss from the lifters; they will just not move as much if the lifter is staying full of oil. The loss of movement is only going to be .080" to .120" of lifter movement maximum, which is going to be between .120" and .180" tops of lift loss at the valve. It usually will be much less lift loss, and if the lifter is staying full, then essentially no loss of lift will occur.

If you're really not seeing any rocker movement, then something is really wrong. Dang..... Are the rocker shafts bolts good? If not, then the fear of wiped cam lobes is the next thought.
 
I saw #3 and #1 move but only slightly due to the lack of pull area. I'm Guessing they did move I just didn't see them due to my angle and not wanting to rip my knuckles off.

This car doesn't run like it has a lobe or loves gone.

I ran through the entire drivers side. No movement from pushin down on the arms.

Maybe thicker oil? I am running 10-30 synthetic right now.
 
After you look good at the rocker movement on all cylinders, then take off the rocker shaft and look for any problems. The shaft should not be grooved where the rockers ride, and the large bolt hole on the underside of the rocker on the driver's side should be over the 2nd rocker stand from the front. (It'll be over the 2nd hole from the back on the passenger's side.)
 
Well, I have used a lot of synthetic oil, and I have never seen the lighter synthetics be particularly good for lifter noises. The actual viscosities tend to be lower (but more stable over temps). So maybe....

Also, which synthetic are you using? Any lighter weight oil these days will not have the older levels of ZDDP needed for higher lift flat tappet cam survival, so hopefully you are using a ZDDP additive.
 
And OK on the driver's side lifters being solid.

This could be down in the clutch area or under the distributor.

Also, feel carefully near and all around the header flange while running to see if you can detect any puffs of exhaust.
 
And a sticking valve has also crossed my mind. Adding some Seafoam or Rislone to the oil and running it a bit before changing would be the easiest treatment.
 
I added Marvel to the oil change I just did.

I was using AMSOil Zrod 10-30 till I decided to do a quick oil change to try to flush stuff out. Current is Molile 10-30 synthetic. Does the same noise.

I'm going to go back to ZRod once I get the pan gasket changed. I will also add some Rislone.

Exhaust leak is my next heck but I doubt it is a leak. I have had a leak before and it didn't sound like this tick.

What could this be in the clutch distro area?

I just put it back together to drive it to my sons football practice. I will see if I can work on looking more at the rockers this weekend.

It really runs strong so I would assume that eliminates a lobe?
 
For sticking valves, you can also rev the engine by hand and sloooowly dribble Rislone down the carb. This will get some on the intake valve stems and clean them and the guides out. But don't do this in the garage or if you neighbors are greenies..... the smoke of the combusing Rislone will be tremendous. Kids will love it, and you won't have mosquitoes around for a while LOL

Be aware that all the 10W30 and lighter weights, synthetic or not, have had the ZDDP levels reduced so you need a ZDDP additive with the nos-tcok cam that you have. Here is a link to a chart of Mobil 1 products that lists the ZDDP levels; you need to be at 1100-1200 or more for your hydraulic flat tappet cam with the levels of lift that you have.

To be sure on the lobes, you either need to look at the cam directly (intake off) or accurately measure rocker movement or valve lift after insuring that all the lifters are holding oil pressure. The only real sure way is to pull the intake. (Do I keep saying that? LOL)

The engine does not seem to be firing perfectly evenly in your audio, but there are a number of things that could be. The idea of the base circle being low on the new cam still is in my mind, and you could just simply have a pushrod(s) that are a bit loose when the cam lobes are on the heel back in the back on that side. Mopar blocks are known to often have slopes up and down on the decks, and you could have a combination of a low base circle on the new cam with a high deck in the back on the driver's side that results in no preload on some of the lifters back in that corner. The only way to know for sure is to pull the intake and measure the lifter preload all over.

Clutch are: Loose clutch over bolt or a cracked pressure plate housing.
Distributor: Maybe a worn hex on the bottom of the shaft....man, that's a REALLY long shot....I'm just thinking it is back in that corner.
 
I dont think anyone has mentioned the elephant in the room. It is very possible that you have wiped a lobe on the new cam. Proper installation, break in procedure and oil / zddp additives are paramount to the life of a new cam and lifters. I would definately not run synthetic oil unless it is specifically formulated for flat tappet cams and has high zinc (zddp) levels. I would also not run any additives other than a zinc additive.

I have been there and wiped a cam by using synthetic oil. They are mostly formated for modern engines with roller cams.

I would suggest removing the lifters one at a time and checking to make sure their lower (cam contact) face is slightly convex. If any are flat or concave your cam and lifters are done.

My 2 cents.....
 
Last edited:
You may not notice a difference in performance with a wiped lobe. The lobe does not entirely grind off.....it just wears enough and eats up the bottom of the lifter that your preload turns into a clearance and you start hearing a valve tick. This is the beginning of a cam failure.

Did you use a zinc additive and break in the new cam (instant first firing, no exteneded cranking and rpms immediately to 2500 to 3000 for 20 to 30 minutes)?
 
Last edited:
when you changed the oil, I assume you changed the filter. Have you cut the filter open? Do you still have the oil you drained? You could do an oil analysis, or try swishing a magnet around in the oil to see if you find anything indicating abnormal wear.
 
Can you tell I really don't want to pull the intake!

I used Comp Cams break in oil. Followed the break in directions to a tee.

Yes filter has been changed with every oil change. However I don't have them anymore. I will make sure to take a sample when the shop does the gasket for me. (I don't feel like laying on my back under the car to change the oil pan gasket.)

I will switch to Dino oil with ZDDP additive on this next oil change.

With the oil pan off would it be possible to snake a camera up from the bottom to see the cam lobes? Would this even show anything?

Also, another reason I don't think it's a lobe, I remember having a similar tick prior to the cam change. It wasn't as pronounced but it was there. Same area. Should I have stated this before we got into all this?
 
You must log in or register to reply here.
-

Back
Top