The Dodge Challenger Message Board

Hi,
Have just put together a 440 with roller cam and hydraulic lifters (from Hughes). Adjustment according to Hughes should be zero lash and then another 1/2 to full turn. However, after doing that repeated times I still have some valve ticking sound like from an old mechanic cam. Shouldn't the hydraulic be tick-free or am I oversensistive?

It should be tick free.

Are you sure it is the lifters you can hear? Quite often what sounds like tappet noise is is fact a slight exhaust leak at the header flange. Headers make any small noise seem louder. In fact I could swear I can hear the exhaust valve closing when I listen near to the header tubes.

Hey this is a problem I had! I would agree 100% with Dave, I bet it is an exhaust leak. Are you using headers or stock manifolds?

I hope he doesn't have all the problems you had Jeff!

But that is a point. Even though it is most likely just a tiny bit of exhaust manifold leak it is still worth checking your pushrods are not hitting anything at full tilt like the intake runners or the underside of the rockers. Eh Jeff?

I dont think it's a exhaust leak.
After I have adjusted the preload, its much better (more silent) for a while (a few miles) and then the ticking gradually increases and come back. When I then make new adjustments I have allways found at least one of the rockers with excessive lash or no preload, which clerly is responsible for the higher noise.
The pushrods are of the type that you cut at the correct length yourself and then press the cup on. I had to cut more than an inch off, and then machine the cup end tap since the corresponding hole in the rod were slightly conical and thus became to tight when the rod was cut.
So my first thought was that the pushrod ends were not sitting tight to the end of the pushrod itself and then gradually were pressed in when the engine was running... This does however not explain why there is a small ticking sound directly after adjustment.
But I will check your theoris.. Thanks, I'll be back.
By the way, anyone that have experience in "cut to length pushrods"?
/ Lars

Are the new lifters getting oil from the feed holes in the engine OK? Check the oilway on the lifter against a normal lifter.
I seem to remember someone over here having problems due to things like low oil pressure or oil leaks around the lifter due to wear in the lifter bore.

Yes, the feeding holes were OK when the engine was put together but I guess that doesn't mean they are OK now...
I adjusted the valves again today and found that I could push down the pushrods in the lifter a little bit as if there were to little oil in the lifter. Don't know if the oil in the lifter got pumped out as i were turning the crank, or if they were not completly filled from start.. Anyone know how long after switching engine off the lifters are completly filled when you are turning the crank by hand during adjustment of lifters?
One idea is that I'm using to thin (5/40) oil and that that together with slightly worn lifter bores causes the lifters not to be completly filled. Oil pressure howerever is good.

As soon as you turn the engine off any valve spring pressure (or if you push down on them) will push the lifters down and force the oil out.

When adjusting them you have zero load on them of course so the small spring inside the lifter body expands the lifter to it's full length. It usually only takes a few seconds to do that.

Going back to the first point. The bleed-down rate of stock lifters is pretty slow. i.e. if you push down on it it will take a minute or so to force the oil out. Rhoads lifters and their like have much faster bleed rates. You can squash them down in a few seconds. So at low engine speeds (and oil pressure) they give you less lift and longer duration. However this causes a tappet type noise.

So if your lifters have a fast bleed down rate it could be that it is this you can hear.

Check with the supplier about this.

What do you think of Lars idea, that he maybe is using to thin oil, Dave?

I do like a thicker oil than that in these old engines. But he says his pressure is fine. Lifter bleed-down rates will be faster with thinner oil I suppose.

It would not hurt to try some 20w-40w oil instead to see what it is like.

Just a comment about roller lifters.

I don't pretend to be any sort of aurthority on roller cams (or anything else!) but I do not like them in street cars that were not originally designed for them. Not if you intend to do a fair bit of mileage.

The roller lifters put quite a large side-load on the lifter bore. It can cause them to wear oval quite quickly. Causing low oil pressure and lifter leak-down.

It is always worth checking lifter bores if you are having any machine work done. Good engine builders like ray Barton always drill them out, sleeve them, and then hone them to the exact size.

mine used to tick and i ask a guy here and he said my oil journal hole might be cloged. he told me to put some tranny fluid in with my oil when i changed it. he said it is alot thinner and would go through where oil would not. it would clean it out. i did it and it worked fine

Lars, I have just read this thread again... I did not realise you were using a roller! I used to have a roller in my 440, But no more! I had a ticking noise in mine a few times, the ticking turned into a knocking followed by bent pushrods and broken rocker arms!
I am not saying this is your problem BUT have you got the right length pushrods? I did'nt! two years of grief, Dave came down and put me right!! If those push rods are touc

440 with hydraulic lifters and adjustable rockers 9.125" 3/8 thick

440 hydraulic roller lifters and adjustable rockers, heat treated, heavy wall pushrods should be 8.375" 3/8 thick.
And it should have a base shape as the blue ringed pic below!