head and cam swap

[gmc67swb]

Here's my problem,was wondering if any of you have ever had this happen...got it all back together started it up and everything was fine after a trip around the block , a lifter was knocking ,ok a little adjustment and all was fine. now the problem is it keeps coming back...have adjusted the lifters 5 times ,on start up its fine no rattle then after its warmed up it starts knocking...new heads ,cam lifters hardened push rods...my thinking is i have a lifter that has a bad spring...if yall have any other idea what could make this happen i sure would appreciate it.....thanks in advance...

[LONGHAIR]

Is it the same one every time? Are you sure that your lock nuts are not slipping? Screw-in studs tight?

[norwegianc10]

Only knocking when warm? Used plenty of assembly lube on the new cam? Did you check that all lifter operated smoothly in their bores?

[pumpkin]

What are the specs on the cam? I'm just putting my 406 together, and when checking the clearances, I noticed that the rods are way too close to the cam lobes. Specs call for min clearance of .050 , and I had about.020. So now I have to take the rods out and grind a bit of clearance on the tops of the rod bolts and connecting rod.

[gmc67swb]

yep same one everytime...

[gmc67swb]

specs on cam. 473/488

[gmc67swb]

starts knocking after warmed up..thats why i think bad spring in lifter... it comes and goes like the lifter is not staying pumped up....

[67dragtruck]

My question would be if you let it cool down without adjusting anything does it start out quiet again before getting warm?

Tom

[Painter D]

Ok heres my .02 . I did the exact same thing in my truck (cam, head swap) , and my truck still does the same thing a little. I work at a Ford dealership in Mesquite , and had several qualified people look at it. Here's the conclusion we came up with, and this could be wrong , but it's all we came up with. First off did you get a roller cam? I didn't , I got a flat tappet hyd. cam. Supposedely the reason my valvetrain chatters so much is because of the oil that is available today. I didn't believe it either. The oil that is made today appearently is no where near the quality it used to be. The mfg. are making oil get thinner as it gets hotter to make these newer vehicles more efficient, and all newer vehicles come with roller cams, not flat tappet. Appearently these newer oils aren't designed for flat tappet cams. So I tried setting and setting the valves but the chatter still came back and it wasn't just 1 of them tapping , it was all of them. From what I gathered the lifters wont stay pumped up because these crappy oils today aren't as thick as they used to be. (If that makes sense?) Until I finally decided to try a thicker oil than 10w 30 the problem stayed there. I found some straight 40w oil and the problem totally went away. I don't know if it will work on your application , but it did on mine, and again I say (I could be wrong) but it works for me. I hope this helps.

[gmc67swb]

Originally Posted by 67dragtruck

My question would be if you let it cool down without adjusting anything does it start out quiet again before getting warm?

Tom

yes ...cold no lifter noise and its just one lifter thats doing it...

[gmc67swb]

Originally Posted by 69chevyshort

Ok heres my .02 . I did the exact same thing in my truck (cam, head swap) , and my truck still does the same thing a little. I work at a Ford dealership in Mesquite , and had several qualified people look at it. Here's the conclusion we came up with, and this could be wrong , but it's all we came up with. First off did you get a roller cam? I didn't , I got a flat tappet hyd. cam. Supposedely the reason my valvetrain chatters so much is because of the oil that is available today. I didn't believe it either. The oil that is made today appearently is no where near the quality it used to be. The mfg. are making oil get thinner as it gets hotter to make these newer vehicles more efficient, and all newer vehicles come with roller cams, not flat tappet. Appearently these newer oils aren't designed for flat tappet cams. So I tried setting and setting the valves but the chatter still came back and it wasn't just 1 of them tapping , it was all of them. From what I gathered the lifters wont stay pumped up because these crappy oils today aren't as thick as they used to be. (If that makes sense?) Until I finally decided to try a thicker oil than 10w 30 the problem stayed there. I found some straight 40w oil and the problem totally went away. I don't know if it will work on your application , but it did on mine, and again I say (I could be wrong) but it works for me. I hope this helps.

no roller...hyd cam..like i said its just one lifter making the noise.....before the swap no noise at all...and thanks for all the advice

[ed2552]

Try a diesel oil with a good break in lube, like Crane Cams Break in oil additive

[67dragtruck]

Originally Posted by gmc67swb

no roller...hyd cam..like i said its just one lifter making the noise.....before the swap no noise at all...and thanks for all the advice

Then it sounds like adjustment isn't helping and it's just related to temp or lifter pump up. The thicker oil suggestion may help. I'm running Rotella diesel oil in my flat tappet motors all the time because of the zinc reduction in the normal oils. I hear they are lowering it in them as well. I'd try one of them or Valvoline VR-1 racing oil, which still has plenty of the additive and have always been pretty thick per grade. What weight and type of oil have you been running?

[gmc67swb]

Originally Posted by 67dragtruck

Then it sounds like adjustment isn't helping and it's just related to temp or lifter pump up. The thicker oil suggestion may help. I'm running Rotella diesel oil in my flat tappet motors all the time because of the zinc reduction in the normal oils. I hear they are lowering it in them as well. I'd try one of them or Valvoline VR-1 racing oil, which still has plenty of the additive and have always been pretty thick per grade. What weight and type of oil have you been running?

Thanks for the advice...i'll try a different oil before i tear it down again, oh yeah running 10w30 valvoline...i'll post back with the results, again thanks for all the input.....

[67dragtruck]

Originally Posted by gmc67swb

Thanks for the advice...i'll try a different oil before i tear it down again, oh yeah running 10w30 valvoline...i'll post back with the results, again thanks for all the input.....

The newer 10w30 oils remind me of water. I remember years ago running straight 30w and it was thick. Now compare it to 10w30 and what a difference. Whatever you do, don't put Mobil1 in it. I had 2 great running motors, that were proven motors and had not had a moments trouble out of either one of them that didn't make it 20 miles on 1 and 60 miles on the other after putting in Mobil1 synthetic before having oil pressure troubles and wiped the bearings.

[Painter D]

Any progress?

[gmc67swb]

Thanks for the input boys... here's what happened on the knocking lifter...according to edlebrock you can use there head bolt kit r standard kit,so i went with arp head bolts.Then they say if useing stamped rockers use .100 longer then standered push rods, and if useing roller rockers you can use standered length push rods.(dead wrong) anyway needless to say every other rocker was sitting down on a head bolt, so there was no way to set the lifters correct,thats the reason for the knocking.....so i wasted a cam and set of lifters, so what i came up with is on the edlebrock heads they are not recessed enough for standered bolts, so you have to use the lenghtened push rods.Just wanted to pass this along if anyone decides to go with the edlebrock heads . Don't be a dumb butt like me always check for clearance on everything could save you alot of time and money.....Maybe this will help someone in the future.....Again thanks!!!!

[royo]

kool thanks for the info

[LONGHAIR]

I merged these posts. The "up-date" was very dis-connected feeling w/o the original post and it's info.

[MikeB]

Read this article on setting pushrod length.

http://www.compcams.com/information/Products/Pushrods/

Also, if you have a flat tappet cam, be sure to use a break-in additive with ZDDP, like CompCams P/N 159. Add this to the oil and, of course, coat the cam lobes and lifter faces with the moly cam lube that comes with a new cam.

If you are using ARP headbolts on Edelbrock Performer or RPM heads, you may want to discard the flat washers in order to get enough headbolt threads engaged in the block. I'd want at least 6 full turns.

IMO, Edelbrock is not really a good company to talk to about cams! There is no way they should have arbitrarily told you to use a specific length pushrod.

[gmc67swb]

Originally Posted by MikeB

Read this article on setting pushrod length.

http://www.compcams.com/information/Products/Pushrods/

Also, if you have a flat tappet cam, be sure to use a break-in additive with ZDDP, like CompCams P/N 159. Add this to the oil and, of course, coat the cam lobes and lifter faces with the moly cam lube that comes with a new cam.

If you are using ARP headbolts on Edelbrock Performer or RPM heads, you may want to discard the flat washers in order to get enough headbolt threads engaged in the block. I'd want at least 6 full turns.

IMO, Edelbrock is not really a good company to talk to about cams! There is no way they should have arbitrarily told you to use a specific length pushrod.

Thanks Mike the pushrod link was very helpful....well it's up and running and everything is fine no more lifter noise and the heads and cam seem to woke that motor up, will no more after a good break-in...thanks for all the help..