I have Morel lifter 4603 preload at 1 turn on the nut in my engine and they are noisy at cold idle until the engine get 160-170 deg. I run my engine (blower) at 130-140 deg so they are always noisy at idle.
I know that i am not the only one with that noisy problem.

What can cause that noise situation?

What oil are you running?

Your a full turn down ?? and they still rattle,

I know my 4603's were a lot noiser with 5/8 a turn, than 1 full turn.

I know the 5045's supposedly want thinner oil, 5w40, but I dont believe thats a noise thing. I think it has to do with whether or not the lifter can purge the chamber properly. Icdedppl has been running 15w50 and 20w50 with his 5045's with no issues though.

However, lately, i've been hearing of way too many morel lifters that are causing headaches. Lifters collapsing and causing problems. I got the pleasure of having to remove a blower, intercooler, distributor, intake, on the dyno because of this not long ago. I know for a fact, at least half dozen oso members recently have had this happen to them as well at startup, even with the recommended 5w40 during initial startup/break in with the 5045's.

I think my next set of lifters are either going to be a johnson hydraulic, or simply switch to solid roller setups.

Also what lobes? I know that's obvious, but my engine guy says I shouldn't have any noise issues with the Morels and the cam he got me. I must admit, I do see some noise concerns/complaints with these lifters.

I have the 4603's and they chatter a little, nothing over bearing, only can hear it with the hatch up

I think there have been threads out there about some noise from the Morel lifters for threads. I know a friend of mine had a couple that would not shut up for him, and he actually sent them in to Morel to be checked. Meanwhile he bought a second set that were quieter, but still made a little noise. Morel didn't find anything wrong with the first set. That was probably 6 or 7 years ago. I know mine make a little bit of noise as well, but see to quiet down once the oil heats up.

There is a thread on the other board that discusses this as well. Lots of talk about oil viscosity over there.

i have had 3 morel,s give me grief,2 were 4603s and 1 5045.i was lucky to have other sets to rob from but still wasted 3 to 4 hours each time changing out the failed lifters.luckily i buy mine from bob madera as he sent me replacements.add in,per bob,s recomendation i initially ran 5w30 oil for start&warm up and still had a failure.

Did they ever inspect the lifters to find out the cause of the issue ? I had another buddy recently tear his engines down and found a couple morels where the tie bars came apart.

i sent them in for inspection but have not heard of their findings,i will call bob monday to find out what they told him.