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Question on Johnson lifters 1007B cam grund So, I put my motor all back together and had a noise at startup that I was thinking was the starter. Turns out I think my valves may be too tight.
It's a 52 Merc with Edelbrock heads, and adj lifters. It was really noisy last summer so I was thinking valves needed adjustment. When I went into it I made cold adjustments of .014 intake and .018 exhaust. All of them seemed to be loose, which is what I expected from the noise. Although the engine was running great before. So does this cam grind need more clearance? What should I set them at? Thanks, Ralph |
Re: Question on Johnson lifters 1007B cam grund Those adjustments would be for rotator type valves. If it still has that type then it should be OK but that would be towards the max clearances.
On the non-rotator types used prior to 1951 INs are set at .012"/EXs are set at .014" on the minumum clearance side. It doesn't hurt to go to the max since it allows the valve to wear in deeper in the pockets over time. There was only about .002" clearance differences between the two types of valves overall. It's normal for a solid type valve train to have a small amount of noise. It should be almost unnoticeable when the engine hood is shut. This is all with a stock cam though. I don't have enough experience with performance type grinds to say one way or the other. Head clearance can be a problem on some cams depending on how much the deck and head surfaces have been machined. |
Re: Question on Johnson lifters 1007B cam grund The cam grinder should be able to tell you the correct clearances. It might or might not match up to any stock grind specs.
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Re: Question on Johnson lifters 1007B cam grund I think you should have used chevy valves as they are longer and in your caase the adhusting screwa are too fare out and won't stay tight. This information has been available on the barn for years. If you have a cam with over .350 lift younshould usr Chevy valves. Keep this in mind.
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Re: Question on Johnson lifters 1007B cam grund So what is the lift on a 1007B?
I'm thinking I need to go back in and set them to .016 and .020 to keep them from making noise? Oh, and Rotowrench, I don't have a hood. :) |
Re: Question on Johnson lifters 1007B cam grund .355 lift
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Re: Question on Johnson lifters 1007B cam grund How is increasing the clearance going to make it quieter?
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Re: Question on Johnson lifters 1007B cam grund Right now it sure sounds like one, or more of the valves are kissing the head.
Also has a little bit of exhaust "popping" noise, never had it before. I did not measure the clearances before I adjusted, just had the feeler gauge out and knew it was a lot more than called for. When I built the motor I used the book specs, unless when I did it this time it wasn't set right? I started at TDC #1, marked the crank at every 90 degrees, and followed the firing order. Every set of valves seemed to be at the the max clearance when adjusted. |
Re: Question on Johnson lifters 1007B cam grund Ron is sure correct about the lifters, a reground cam with standard thickness adjusting screws and Ford valves does not work. The correct lifters have thick heads to make up the difference.
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Re: Question on Johnson lifters 1007B cam grund We set most Flatheads valves at a cold setting of .010" (intake) and .012" (exhaust) and find these clearances work fine.
I don't believe the clearances are causing your issue and setting them looser will just tend to make matters worse! Thanks, Gary in N.Y. P.S. With respect to using the longer Chevy valves we prefer to use some .060" or .080" thick lash caps instead, does the same job as having a longer valve but doesn't "mess up" the spring hgts on you! You could still add these into the program now! |
Re: Question on Johnson lifters 1007B cam grund Quote:
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Re: Question on Johnson lifters 1007B cam grund If one or more were touching, there could now be some slightly bent valves which will let some of your fuel air mix by. Maybe that's the popping in the exhaust now. It'll cost you a head set but it might be worth it for piece of mind.
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Re: Question on Johnson lifters 1007B cam grund Ditto as above. Except just cut the heads for clearance.
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Re: Question on Johnson lifters 1007B cam grund The valve to head clearance needs to be more than the few thousandths you could pick up with lifter adjustment!
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Re: Question on Johnson lifters 1007B cam grund Try "foiling" the valves the same way we do pistons to check head clearances.. Place the heads with gaskets finger tighten a few head bolts , remove sparkplugs and gently hand turn the engine. If you experience any resistance stop cranking. Measure crushed foil balls to ascertain if a valve it tapping the head.
As suggested check with cam grinder for valve adjustment specs. I run a Howard M6 which has a .335 lift and the recommended adjustments are In. .012, Ex .014 as per cam provider. |
Re: Question on Johnson lifters 1007B cam grund I don't know what else it could be, the only thing I have changed is the valve lash settings.
It it's definitely making a noise that wasn't there before. ????? |
Re: Question on Johnson lifters 1007B cam grund Had one of those "what is it" taps show up. Foiled pistons and valves, all Okay?
Opened it up three times and checked valve adjustments, all Okay? Finally surrendered and have been driving it. I am the only one that seems to hear it now. Folks always said that I had a screw loose...Guess I have to finally agree with them. Hope you get it figured out, please let us know. |
Re: Question on Johnson lifters 1007B cam grund FWIW If a valve is set too tight, it will not close and the engine will idle rough. Too loose and it will be noisy and not let the valve fully open. I've been led to believe that the clearance cold allow for expansion, thus the greater clearance for the hotter exhaust valves. Aside from sealing the combustion chamber the valve needs to be fully seated in order to cool. When you installed the new cam you should have checked the valve to head clearance.
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Re: Question on Johnson lifters 1007B cam grund I admit I did not measure the valve to head clearance when I built the motor, but the heads were new and I have had no clearance issues for the first 1400 miles of this engine.
Thing is, I adjusted them the same when I first built the motor. Go figure. I'm thinking that it's not all of them that are doing it, I just must have one or two "off" a little? |
Re: Question on Johnson lifters 1007B cam grund Did you use the same brand/type head gasket the second time?
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