Valves tapping and a possible solution

[KYJ10]

I was talking to a guy who races AMC cars for the better part of 30 years now and he gave me some info on how to resolve my clicking lifters. He said you can isolate the ones that are clicking(my front 2 on the drivers side). He said to remove the rail that holds them down. Where they make contact with the head, machince off about .10 from the contact point of the rail, closest to those lifters and retighten. If it still has some noise, take another .10 off the bottom and that should pull the rail down tighter on the 2 valves. Any one ever hear off this? I hope I explained it clearly. Dennis

[Crazy_Jeepman]

Hmmmm Well it could work, but I highly doubt it is a solution for a high mile engine with bad lifters and possible cam failure. I would just fix it correctly, instead of machining material off of a wore out valve train to correct a problem easily corrected with replacement. Besides the much simpler solution is to get 0.010 longer push rods.

[Al Johnson]

I question the .10 and .20 measurements. At .20, that's dang near a quarter inch! Are you sure he didn't say, or mean, .010 and .020?

And I'm with Crazy, it's better by far to fix it right than to jury-rig some machining to the head that's permanent, and may or may not fix the problem. Even then it's not a fix, it's a mask. Then if you did fix it right later, what would you do about the machined head? By the time you take the head off to machine it, you might as well do a proper repair.

Just my $0.01! (I'm cheap!)

Al

[Zack172]

I agree, just fix it right. Al, I think he meant machine 0.010 off the rocker arm where it contacts the head, not machine the head.

[KYJ10]

Yes I did mean .010 and it is off the bottom of the rail where it makes contact with the head. Just by the lifters that are making noise. I cannot afford to rebuild the heads, much less the engine, so If I can get by with a temp fix on this tapping, what the hey.

[Al Johnson]

Re-reading the original post, yes, you did say machine off the bottom of the rail. My mistake.
Have you thought of buying a couple of longer pushrods? It's my understanding, just by what I read, that the AMC pushrods are the same as SBC's, and they are available in different lengths. This would have the same effect, but be cheaper than haveing to replace AMC parts in the future, if you decide to rebuild at some time. Not positive this would work, as I don't know what lengths the rods come in, but it's worth looking into as an alternative.
Also, not sure if this would be the case for you, but when I disassembled my 360 for rebuild, I found that the #1 cam lobes were almost flat. I'm pretty sure that could create a tapping sound, as the cam has the wrong profile when that badly worn. Might be a good idea to measure the cam lift. Also, you might look into putting new lifters in. You can't use old lifters with a new cam, but you can put new lifters on an old cam, if the cam is in resonable shape.

[kyjman]

Hey kyj10 I'd just put up with the noise before I went and maybe messed up an otherwise good running motor. My 258 sounds like a thrashing machine but it will sound like that all day long...its runs very good. I turn up the radio a little louder and it drowns out the lifter noise.

[buggy boy]

my tap on the pasenger side and i am thinking of just rebuilding the whole engine. When i replaced the rear main this spring, i noticed that the main bearings had some wear. I did a compression test and i get around 130 PSI in every cylinder. I just took it on a 2,100 mile trip from Maine to Virginia and back and it ran fine but i notice the lifter was tapping a little more(towing a uhaul trailer up the big hills in PA) What do u all think? Rebuild the whole thing, drive it until it drops or rebuild the upper end? Any suggestions?

BTW....i was told it could be just a bad exhaust manifold gasket on the Passenger side??????

[ December 03, 2002, 12:13 AM: Message edited by: buggy boy ]