360 hydraulic lifter valve lash

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cool thanks man. i put the lifters in dry and bolted my rockers down and i can get .040 feeler gauge between the valve tip and rocker on every one that is riding the base circle of the cam. i did not pump oil into the lifters and i know the lifter seat height is as high as its going to get. i can imagine that it will make a bit of a racket if i were to start it even after the lifters have pumped up. this sucks lol
 
Good evening:) What's your plan now? are you gonna get longer pushrods? I assume you removed the lash caps when you got that .040 clearence. I always tried to run minimal preload on my hyd. builds to try and gain a few hundred R's at the limit, but with these lifters these days i'm not sure what i would do..........
 
evening Rick, yes i took the caps off and i have the same issue i had before except i managed to gain .020 with the new rockers. this was the reason i put them on in first place. i was hoping to close the gap with new parts, but its just not happening. im at around .035 - .040 . its just so very little but enough to bug me and im sure it would clatter if i were to run it.
 
73AbodEE said:
evening Rick, yes i took the caps off and i have the same issue i had before except i managed to gain .020 with the new rockers. this was the reason i put them on in first place. i was hoping to close the gap with new parts, but its just not happening. im at around .035 - .040 . its just so very little but enough to bug me and im sure it would clatter if i were to run it.
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It would probably make alot a noise that wide. Wonder if there is a member here thats accumulated a bunch of pushrod over the years that would have a lenght that's close enough to work for you. And maybe just for the ride:grin:. If i had'em they'ed be yours. Well however it gets straightened out i hope it's one of your best runnin' engines you've had:thumblef:.
 
Lance, measure your pushrods. I have a set and if they are longer than yours I can send them to you. I won't be home until Thursday morning though.
 
they are the 7.53 standard 77 360 pushrods. i dont know if a 7.55 would be enough and maybe 7.60 would work. i found some on summits site, but damn if they want 120.00 bucks for them. Thank you Bruce , that would be awesome if have some laying around.

Rick this engine has been real good so far, until it ate a lifter. im thinking the lash caps may have been too much and destroyed a lifter, but who knows. im confident in the lifters because these are the same exact kind that i just put in a 318 and they are living very happily lol
 
73AbodEE said:
do you mean how far down the seat is when the pushrod has the lifter compressed?
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No - Preload is how far down the plunger goes when the rockers are torqued and the lifter is on the base circle. Reason I ask is you need much longer than .040 if you want to have the lifter installed properly. That's assuming the plunger is not being pushed in a little while you're using your feeler gages. If you measure and check lifter preload as I said in the PM - and you can do that with your feeler gages under the tip of the rocker you just need to look at the lifter to make sure there's preload - you'll then be able to get the pushrod length you need. If you have .040 of open space, or "lash", you need a pushrod that's .065-.090 longer to take up that space and give proper preload to the lifters.
 
with the lifter on base circle and i take up the slack without plunging the lifter i have .040. when i take the rocker and bottom out the lifter , i have .135 . so subract the .040 and that gives the lifter .095 of travel. so do i want to meet somewhere in the middle to add to the .040 to get a correct length? say .045 + .040? my stock pushrod is 7.53 + the .95 would be right around 7.60. is my thinking on track here? what is the ideal preload on a hydraulic lifter that has .090 of travel?
 
................So let me get this straight.........no new springs, u never measured the depth of the pushrod seats in any of the lifters, no longer pushrods as of yet, so ur flirting with disaster.........how thick is the head gasket u installed?....................kim..........
 
oldkimmer said:
................So let me get this straight.........no new springs, u never measured the depth of the pushrod seats in any of the lifters, no longer pushrods as of yet, so ur flirting with disaster.........how thick is the head gasket u installed?........then just went ahead with what u were going to do in the 1st place, so what has the 25 years of the so called engine work taught u?............kim..........
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wow, thanks for the encouragement. the pushrod seats have .090 of travel. changing the springs had no effect on valve stem height. the head gaskets are factory thickness and have not been messed with. im not just going to go out and buy any old longer pushrod without knowing exactly what i need. its all good i will figure it out on my own, i just wanted some input not insults........thanks.........Lance..........

im not a complete know it all nor am i a complete idiot
 
im not a complete know it all nor am i a complete idiot[/QUOTE]

Are you sure? :D:D:D

I've never measured the lifter travel before, but .090 seems a little short to me. Maybe someone could confirm that on another lifter. May be right though? The reason i'm bringing it up is if that's all the travel you have, it seems you'd have to be careful about too much preload? I could see the possibility of some float if they pumped up very much at higher rpm's.

Bare with me, i'm just trying to learn, Rick
 
OldmanRick said:
I've never measured the lifter travel before, but .090 seems a little short to me. Maybe someone could confirm that on another lifter. May be right though? The reason i'm bringing it up is if that's all the travel you have, it seems you'd have to be careful about too much preload? I could see the possibility of some float if they pumped up very much at higher rpm's.

Bare with me, i'm just trying to learn, Rick
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im still learning too Rick. its all good though, its not rocket science, i will get her figured out today. no biggie . i was only going on with all this so that maybe down the road someone else with a similar problem would be able to learn as well. but apparently , its the sign of a dumbass
 
I don't think anybody's trying to accuse you of bein an idiot. Lemmie see if I can help. I am pretty good at layman's terms because my mind is pretty simple. lol

Since Chrysler engines have non adjustable valve gear, ALL of the factory specs and clearances are critical. That includes head gasket thickness, pushrod length and any amount that's been milled off the block and heads.

See, when you mill the block and heads of an engine, you're effectively makin the pushrods longer. When material is removed from the block and or head faces, the pushrods actually push on the rockers more than they normally would.

I think you understand that much from talking to you on here though. Lifter preload though is somewhat tricky to understand. As mentioned above, lifter preload is the amount that the pushrod pushes the plunger into the lifter with the cam lobe on the base circle of the particular lifter being measured. You with that so far?

So, milling the heads or block, or running thinner head gaskets makes that lifter preload MORE, or pushes the plunger into the lifter body more. Lifter preload works best between .020-.060"...opinions vary, but that's a generally accepted range. I like preload on my engines on the light side, like .020.

That's why measuring everything is so critical on a Chrysler engine. I even measure it all out if I am using adjustable rockers. It's just the right way to do it. I think what has happened to you is this. Aftermarket cams are ground on a reduced base circle compared to stock. In other words, the lobe on an aftermarket cam is "moved" if you will away from the centerline of the core to open the valve more. That's what reduces the base circle.

If you used stock length pushrods, there is your problem, more than likely. You don't have enough lifter preload, because of the reduced cam base circle. You can solve that a couple of different ways.....or both. With correct length pushrods and or adjustable rockers. I would do both. That will assure correct rocker sweep. I hope I helped more than I confused. This is one time when I really don't think a smartass respose is warranted, so I didn't give one. lol
 
.............What i mean is....u just cant throw things together anymore and expect them to work,as said earlier........u have to measure, measure, measure and measure again.......and have all the correct parts not just some of them......if something isnt right, find out what it is and fix it then and there.......its way easier out of the vehical where u can do everything alot easier..............kim...........
 
StrokerScamp said:
I don't think anybody's trying to accuse you of bein an idiot. Lemmie see if I can help. I am pretty good at layman's terms because my mind is pretty simple. lol

Since Chrysler engines have non adjustable valve gear, ALL of the factory specs and clearances are critical. That includes head gasket thickness, pushrod length and any amount that's been milled off the block and heads.

See, when you mill the block and heads of an engine, you're effectively makin the pushrods longer. When material is removed from the block and or head faces, the pushrods actually push on the rockers more than they normally would.

I think you understand that much from talking to you on here though. Lifter preload though is somewhat tricky to understand. As mentioned above, lifter preload is the amount that the pushrod pushes the plunger into the lifter with the cam lobe on the base circle of the particular lifter being measured. You with that so far?

So, milling the heads or block, or running thinner head gaskets makes that lifter preload MORE, or pushes the plunger into the lifter body more. lifter preload works best between .020-.060...opinions vary, but that's a generally accepted range. I like preload on my engines on the light side, like .020.

That's why measuring everything is so critical on a Chrysler engine. I even measure it all out if I am using adjustable rockers. It's just the right way to do it. I think what has happened to you is this. Aftermarket cams are ground on a reduced base circle compared to stock. In other words, the lobe on an aftermarket cam is "moved" if you will away from the centerline of the core to open the valve more. That's what reduces the base circle.

If you used stock length pushrods, there is your problem, more than likely. You don't have enough lifter preload, because of the reduced cam base circle. You can solve that a couple of different ways.....or both. With correct length pushrods and or adjustable rockers. I would do both. That will assure correct rocker sweep. I hope I helped more than I confused. This is one time when I really don't think a smartass respose is warranted, so I didn't give one. lol
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Stroker thank you. this is exactly what i needed to know. i didnt mean to be a ***** about it but this is the answer i needed. and thank you for giving me a break LOL now that i know this , the rest is cake
 
oldkimmer said:
.............What i mean is....u just cant throw things together anymore and expect them to work,as said earlier........u have to measure, measure, measure and measure again.......and have all the correct parts not just some of them......if something isnt right, find out what it is and fix it then and there.......its way easier out of the vehical where u can do everything alot easier..............kim...........
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my apologies for coming off like an *** kim, i have never had to deal with lifters 101 . i just needed to know the ideal preload .like i said in my PM, i follow your posts and i have learned a lot from you and SS and many others. even with years of working on this crap, im still finding new things out on the way ,that were never an issue before. thank you guys for all your help.
 
Hay no problem dude. We all get frustrated with stuff. I am glad I said somethin in all that hooha that helped you. lol
 
..............Lance, i was alittle harsh on u, sorry 4 that..........make sure u get some new springs.......mopar recommends P4120249, i'm not sure but i think some ppl use a sb chevy pushrods for longer legnth.....good luck 2 ya.............kim..............
 
You could always get a couple of adjustable pushrods to use to get the correct length.
 
OK Stroker, you can zing him now! I dealt with stamped rockers once., and ended up giving them to someone for free, went right for the proven 273 rockers and pushrods. Still run them and the same pushrods going on 3 cams now. I have since moved on to adjustable roillers but same deal. I can use these for many cams to come, not be stuck with one cam with custom pushrods and stamped rockers whos ratios are all over the board. Dont think of a hydro lifter as pumping up, think of it as back filling the slack with uncompressible fluid. You need a little preload so the piston of the lifter doesnt ever hit the snapring in operation. They are not designed to take that. So with a hydro and an adjustable rocker, get the lifter on the base circle with any method described here, and spin the pushrod in your fingers. Tighten the adjuster until you feel the slightest tension and then turn 1/2-1 turn (preload) more. Lock them down...your done. Eg. At 24 TPI, 1 turn = .040 preload, 1/4 turn =.010 preload. 1.5 turns =.060, get it? Measure your adjusters for TPI and use formula 1/TPI=preload per turn.
 
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