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changing lifter preload #195216 01/16/09 03:58 PM 01/16/09 03:58 PM
Joined: Oct 2007 Posts: 3,889 Oregon hooziewhatsit OP master
hooziewhatsit OP master Joined: Oct 2007 Posts: 3,889 Oregon	'72 W200, 318. I recently re-did the top end and put this cam & new lifters in. Heads got shaved just enough to be flat again. http://store.summitracing.com/partdetail.asp?part=LUN%2D60400LK&autoview=sku So I finally got around to checking the preload on the lifters The lifters are supposed to have .020" to .060". About half of them are fine, and the other half are borderline too short. I figure that's why a couple are making noise I measured preload by scoring a mark on the pushrod, then unbolting the rocker assembly, letting the PR come back out, and scoring another mark. How long are the stock pushrods on a 318 supposed to be, so I can buy some longer ones? I measured 7.478" with my 6" dial calipers, so that may not be accurate. My FSM gives every other spec but that one. Thanks, -Dave If you ever find yourself in a fair fight, your tactics suck.

Re: changing lifter preload [Re: hooziewhatsit] #195217 01/16/09 04:19 PM 01/16/09 04:19 PM
Joined: Jan 2003 Posts: 16,123 Grand Haven, MI patrick I Live Here
patrick I Live Here Joined: Jan 2003 Posts: 16,123 Grand Haven, MI	according to this: http://www.angelfire.com/ca/mikesspot/318specs.html for a police 318 (flat tappet cam) 7.505-7.525" what head gaskets did you use? OEM ones are ~.020" steel shims, the ones that come in most jobber kits are ~.054" thick. switching to say the Mr. Gasket .024-.028" thick composite gaskets would raise compression back up some and take care of your pushrod length issue. Last edited by patrick; 01/16/09 04:22 PM. 1976 Spinnaker White Plymouth Duster, /6 A833OD 1986 Silver/Twilight Blue Chrysler 5th Ave HotRod SOLD!* 2011 Toxic Orange Dodge Charger R/T 2017 Grand Cherokee Overland 2014 Jeep Cherokee Latitude (holy crap, my daughter is driving)

Re: changing lifter preload [Re: patrick] #195218 01/16/09 04:36 PM 01/16/09 04:36 PM
Joined: Oct 2007 Posts: 3,889 Oregon hooziewhatsit OP master
hooziewhatsit OP master Joined: Oct 2007 Posts: 3,889 Oregon	heh heh, that would make a difference. I bought a complete engine gasket set (fel-pros I believe). I didn't measure them, but they sure weren't .020". .054" is much closer to what they seemed to be. Wasn't looking forward to opening it up again, but it may be nice to get a little more compression back. Until then can I leave it ticking? Thanks, -Dave Last edited by hooziewhatsit; 01/16/09 04:39 PM. If you ever find yourself in a fair fight, your tactics suck.

Re: changing lifter preload [Re: hooziewhatsit] #195219 01/16/09 05:31 PM 01/16/09 05:31 PM
A Anonymous Unregistered
Anonymous Unregistered A	If the valve tips are not the same height it will put the preload all over the place--typical with a valve job done on a stock head--the exh tips will usually be higher--non mopar shops overlook correcting them--MELLING makes a 030 long pushrod available from any machine shop or many auto part retailers In a stocker it will cure the problem and they are cheap

Re: changing lifter preload [Re: ] #195220 01/16/09 06:06 PM 01/16/09 06:06 PM
Joined: Jan 2003 Posts: 25,200 Upper Midwest M MoparforLife Too Many Posts
MoparforLife Too Many Posts M Joined: Jan 2003 Posts: 25,200 Upper Midwest	Quote: If the valve tips are not the same height it will put the preload all over the place--typical with a valve job done on a stock head--the exh tips will usually be higher--non mopar shops overlook correcting them--MELLING makes a 030 long pushrod available from any machine shop or many auto part retailers In a stocker it will cure the problem and they are cheap You have that a little backward. If the valve job is done without but grinding the valve stem tips they will be slightly higher (depending on how deep the seats and faces were cut). Therefore the valve stem would be taller against the rocker pushing the pushrod deeper int to the lifter increasing preload. what is needed in most cases after a valve job is a shim under the spring to bring the installed valve spring height back into specs. Lots of times it is a relativley loose valve spring that is causing a slight click.

Re: changing lifter preload [Re: MoparforLife] #195221 01/16/09 07:42 PM 01/16/09 07:42 PM
Joined: Oct 2007 Posts: 3,889 Oregon hooziewhatsit OP master
hooziewhatsit OP master Joined: Oct 2007 Posts: 3,889 Oregon	When I had the heads worked on they needed all new exhaust seats. And come to think of it, while I was checking the preload, I did run a straight edge over the valve stems(?) and the valve for #1 exhaust was slightly lower than the rest. I bet that's where it's coming from. Thanks all, -Dave If you ever find yourself in a fair fight, your tactics suck.

Re: changing lifter preload [Re: hooziewhatsit] #195222 01/16/09 07:45 PM 01/16/09 07:45 PM
Joined: Jan 2003 Posts: 25,200 Upper Midwest M MoparforLife Too Many Posts
MoparforLife Too Many Posts M Joined: Jan 2003 Posts: 25,200 Upper Midwest	New seats could pull the stems down but a competent shops should make sure to seat them deep enough to get the proper spring installed height. Or if not new seats us a shim to get the proper installed height to have proper spring pressures.

Re: changing lifter preload [Re: MoparforLife] #195223 01/16/09 10:04 PM 01/16/09 10:04 PM
Joined: Oct 2007 Posts: 3,889 Oregon hooziewhatsit OP master
hooziewhatsit OP master Joined: Oct 2007 Posts: 3,889 Oregon	moparforlife, I'm not seeing how a shim would help? If the valve went too far into the head, the shim would get the spring rate back where it should be. When I tear into the bottom end this summer I'll have everything looked at again. Until then, a local parts place claims they can get a 7.545" pushrod for $2.25 I'll put that in, check the new preload, and go from there. Thanks for the help, -Dave If you ever find yourself in a fair fight, your tactics suck.

Re: changing lifter preload [Re: hooziewhatsit] #195224 01/16/09 10:14 PM 01/16/09 10:14 PM
Joined: Jan 2003 Posts: 25,200 Upper Midwest M MoparforLife Too Many Posts
MoparforLife Too Many Posts M Joined: Jan 2003 Posts: 25,200 Upper Midwest	Quote: moparforlife, I'm not seeing how a shim would help? If the valve went too far into the head, the shim would get the spring rate back where it should be. When I tear into the bottom end this summer I'll have everything looked at again. Until then, a local parts place claims they can get a 7.545" pushrod for $2.25 I'll put that in, check the new preload, and go from there. Thanks for the help, -Dave The purpose of valve spring shims is to get the valve spring installed height to what is supposed to be.They are not meant to be used to increase spring pressures. They will when use properly shorten the spring installed height and therefore by shorting the spring height XXX amount will increase pressure - hopefully within specs but with a used spring with countless miles it is doubtful. In order to get the valve stem back into specs if seated deep but grinding the valve stem may be used as stated in my posts. This may also require the use of shims to get the valve spring installed height.

Re: changing lifter preload [Re: MoparforLife] #195225 01/16/09 10:29 PM 01/16/09 10:29 PM
Joined: Nov 2003 Posts: 36,040 Lincoln Nebraska R RapidRobert Circle Track
RapidRobert Circle Track R Joined: Nov 2003 Posts: 36,040 Lincoln Nebraska	Quote: The purpose of valve spring shims is to get the valve spring installed height to what is supposed to be.They are not meant to be used to increase spring pressures. I thought that shims were for shortening the installed height to increase the spring pressure(at max lift)? live every 24 hour block of time like it's your last day on earth

Re: changing lifter preload [Re: RapidRobert] #195226 01/16/09 10:42 PM 01/16/09 10:42 PM
Joined: Jan 2003 Posts: 25,200 Upper Midwest M MoparforLife Too Many Posts
MoparforLife Too Many Posts M Joined: Jan 2003 Posts: 25,200 Upper Midwest	Not nessessarly to increase pressure. That is a secondary effect of shortening the spring to proper installed height with the use of shims. It a known fact that shortening the spring by squeezing it together increases the pressure so if it is installed at to great an installed height the pressure will be on the light side, especially using standard springs. IE: A valve and seat ground to the point of seating .020 deeper than spec and therefore the installed height is at 1.720 instead of the 1.68-1.70 spec. A spring that loose will have significantly less pressure that if it were installed at spec 1.70. A ,020 shim is used to bring the spring back to spec installed height and the pressure will rise accordingly. This will not adjust the valve tip which will also be too high requiring it to be but ground to bring back down to correct geometry. Clean it, if it's Dirty. Oil it, if it Squeaks. But: Don't fix it, if it Works!

Re: changing lifter preload [Re: MoparforLife] #195227 01/16/09 10:48 PM 01/16/09 10:48 PM
Joined: Nov 2003 Posts: 36,040 Lincoln Nebraska R RapidRobert Circle Track
RapidRobert Circle Track R Joined: Nov 2003 Posts: 36,040 Lincoln Nebraska	I missed the part about the valve tip aspect. I got it. Thank you. live every 24 hour block of time like it's your last day on earth

Re: changing lifter preload [Re: RapidRobert] #195228 01/16/09 10:59 PM 01/16/09 10:59 PM
Joined: Jan 2003 Posts: 25,200 Upper Midwest M MoparforLife Too Many Posts
MoparforLife Too Many Posts M Joined: Jan 2003 Posts: 25,200 Upper Midwest	Quote: I missed the part about the valve tip aspect. I got it. Thank you. Corrected my math but the effect and example is still the same. Clean it, if it's Dirty. Oil it, if it Squeaks. But: Don't fix it, if it Works!

Re: changing lifter preload [Re: MoparforLife] #195229 01/17/09 10:16 AM 01/17/09 10:16 AM
A Anonymous Unregistered
Anonymous Unregistered A	Yea yea I was just saying they will be all over the place unless a good shop did the work--when new seats go in and all..non mopar shops always seem to overlook this and I suggested longer because he had some rattling --the straight edge is your friend

Re: changing lifter preload [Re: ] #195230 01/17/09 10:23 AM 01/17/09 10:23 AM
Joined: Mar 2008 Posts: 5,746 Ontario, Canada Dodgem master
Dodgem master Joined: Mar 2008 Posts: 5,746 Ontario, Canada	Check your pushrods the are notorious on small blocks for wearing and many may be worn short. Buy new they are dirt cheap. also check the rockers they wear in the rod sockets too

Re: changing lifter preload [Re: Dodgem] #195231 01/17/09 10:55 AM 01/17/09 10:55 AM
Joined: Jan 2003 Posts: 25,200 Upper Midwest M MoparforLife Too Many Posts
MoparforLife Too Many Posts M Joined: Jan 2003 Posts: 25,200 Upper Midwest	Get yourself a set of push rods from summit and Summit brand they are good and will work for your. Are you sure that you haven't got a little dirt in a lifter. If your lifters are preloading at all they shouldn't be noisy. A lot of racers put the preload at vertualy 0. Borderline clicking. Measure your installed height it could also be a spring that is installed too long without the above mentioned shims. thie will also click and sound like a loose lifter. It takes more than a truing trim milling off a head to require different pushrods and they would be shorter if needed and even with the addition of a thicker head gasket overcompensating for the trim you shouldn't have gained enough thickness to require a longer push rod unless you were borderline to start with. OEM push rods are 7.514 inches long +/-

Re: changing lifter preload [Re: MoparforLife] #195232 01/23/09 03:21 PM 01/23/09 03:21 PM
Joined: Oct 2007 Posts: 3,889 Oregon hooziewhatsit OP master
hooziewhatsit OP master Joined: Oct 2007 Posts: 3,889 Oregon	Thanks for all the replies. I just took the passenger side VC & rockers off, and ran a straight edge over the valve tips. The #6 Exhaust valve is (much) higher than the rest. So, that one could have too little spring pressure, and the spring itself could be clicking? Here are the new pushrods I got. (new on the left, old on the right). My old ones have the tip machined off. Will the new ones work, or will they have issues by not having that extra room at the tip? The old ones do not oil through. Thanks -Dave 4968032-untitled.JPG (38 downloads) If you ever find yourself in a fair fight, your tactics suck.

Re: changing lifter preload [Re: hooziewhatsit] #195233 01/23/09 03:33 PM 01/23/09 03:33 PM
Joined: Jan 2003 Posts: 25,200 Upper Midwest M MoparforLife Too Many Posts
MoparforLife Too Many Posts M Joined: Jan 2003 Posts: 25,200 Upper Midwest	did you have new valve seats put into any of the seats. Sounds a lot to me like there were new seats put in and the valves were not seated deep enough into the new seats and therefore the valve stem through the head would be short as would the installed height of the valve spring. That would explain the shallow preload. Check and make sure that your installed height is correct. It should be 1.68-1.7o from the spring seat to the top of the spring below the retainer.

Re: changing lifter preload [Re: MoparforLife] #195234 01/23/09 03:44 PM 01/23/09 03:44 PM
Joined: Oct 2007 Posts: 3,889 Oregon hooziewhatsit OP master
hooziewhatsit OP master Joined: Oct 2007 Posts: 3,889 Oregon	Yes, it got all new exhaust seats. I'd have to find the paper to see if it got any new intake seats. I'll go see if I can measure the spring height right now Thanks, -Dave If you ever find yourself in a fair fight, your tactics suck.

Re: changing lifter preload [Re: hooziewhatsit] #195235 01/23/09 04:15 PM 01/23/09 04:15 PM
Joined: Oct 2007 Posts: 3,889 Oregon hooziewhatsit OP master
hooziewhatsit OP master Joined: Oct 2007 Posts: 3,889 Oregon	Just measured them all on the passenger side. They're all over the place, and quite a bit short. Granted, my dial calipers are a tight fit, and the head is installed, so there's some lee-way in the measurements. Intake varies from 1.612" to 1.646". Exhaust varies from 1.612" to 1.664" (that's by far the tallest valve). Maybe I should just invest in some adjustable rockers Thanks, -Dave Last edited by hooziewhatsit; 01/23/09 04:26 PM. If you ever find yourself in a fair fight, your tactics suck.

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