New lifters and old cam?

Posted By: HitIt

New lifters and old cam? - 04/18/11 05:00 AM

Hi all-
I've got a couple hydraulic lifters in my 440 that don't seem to pump up as well as others resluting in some play in the rocker.

What is the thought on replacing lifters only and not the cam? Is this done without issues? Do I need to break the lifters in in any particular way?

Cam is a basic 488 lift made by Elgin.

Thanks!

Posted By: 70AARcuda

Re: New litters and old cam? - 04/18/11 05:25 AM

no problem with new lifters on old cam..

just went you start the engine...you need to break in cam again...

Posted By: Kern Dog

Re: New litters and old cam? - 04/18/11 07:05 PM

Quote:

no problem with new lifters on old cam..

just went you start the engine...you need to break in cam again...

Well... technically you are mating the new lifters to the old cam. One thing to consider: What caused the lifters to degrade? You might want to measure the lobes from the bad lifters to ensure that they match the other lobes. If there is ANY sign of heavy wear, replace the cam. Once the surface hardness starts to wear away, cams will fail quickly.

Posted By: HitIt

Re: New litters and old cam? - 04/19/11 03:37 AM

Thanks for the info guys.
The lifters in question seem spongy like they have a 1/4" of movement in the hydraulic mechanism if that makes sense.
Does that still seem like the cam could be bad or more likely a bad lifter?
I completely understand the reason behind measuring the cam just wondering if I'm on the right track with the bad lifter idea.
Thanks!

Posted By: RapidRobert

Re: New litters and old cam? - 04/19/11 03:45 AM

Quote:

just wondering if I'm on the right track with the bad lifter idea.

More info please. What's making you think some of the lifters may b bad, something doesn't sound right

Posted By: 70AARcuda

Re: New litters and old cam? - 04/19/11 03:51 AM

Quote:

Quote:

no problem with new lifters on old cam..

just went you start the engine...you need to break in cam again...

Well... technically you are mating the new lifters to the old cam. One thing to consider: What caused the lifters to degrade? You might want to measure the lobes from the bad lifters to ensure that they match the other lobes. If there is ANY sign of heavy wear, replace the cam. Once the surface hardness starts to wear away, cams will fail quickly.

I have done it several times in big solid lifter cams..and never had a problem...

Posted By: Von

Re: New litters and old cam? - 04/19/11 04:42 AM

I have one solid cam that has had 4 sets of lifters on it over the years. No problems....

Posted By: HitIt

Re: New litters and old cam? - 04/19/11 05:16 PM

Quote:

Quote:

just wondering if I'm on the right track with the bad lifter idea.

More info please. What's making you think some of the lifters may b bad, something doesn't sound right

Hi Robert-
In general the engine has a clattery sounding valve train, especially on one side - details are below.

compared to most others in the engine- a couple rockers have what seems to be excess play in them when the valves are unloaded. I can push the pushrod down into the lifter on the 'loose' ones and the lifter diaphragm will move in and out while a slight slurping noise is noticable. The tighter rockers don't do this.

It happens when the engine is cold especially, but even after it's warmed up. Makes me think the lifters could have failed and won't hold their hydraulic pressure.

Thanks very much for the help. Apprecite it.

Posted By: Kern Dog

Re: New litters and old cam? - 04/19/11 06:20 PM

Spongy feeling lifters.... NOT good. In two instances, I had lifters feel spongy. Both times they were worn enough on the bottom to have a small hole visible. This hole allowed oil to bleed out and prevent the lifters from holding oil pressure. In these cases, the cam and lifters needed to be replaced. I'm not trying to be a doomsayer, this is just what problems I have encountered.
Also, if you have access to a selection of rocker arms, pick through and measure the holes that the shaft runs through. I did this to get a set with the tightest clearance. This may help minimize valvetrain rattle.

Posted By: HitIt

Re: New litters and old cam? - 04/19/11 09:40 PM

Thanks for that info. I am definitely going to inspect the surfaces soon, and even measure the lift between the valves to see if one of the cam lobes is 'different'.