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| stugray |
Oct 14 2012, 02:06 PM
Post
#1
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Advanced Member ![]() ![]() ![]() ![]() Group: Members Posts: 3,825 Joined: 17-September 09 From: Longmont, CO Member No.: 10,819 Region Association: None |
Ok, so I bought the deck height measurement tools from the group buy.
But I cannot figure out exactly how the OP intended to use the middle plate. I have been trying to measure my deck height accurately for weeks now and I either am not doing it right, or I have a problem. I have the EMW AA cylinders & KB Hypereutectic pistons - brand new. I am measuring with no shims under the cyls. I bolt the holddown tool on two cyls with pistons installed and torque to spec (24 ft-lbs) I set TDC on the cyl I am about to measure with a mag base & dial indicator using the middle of the piston as reference. I then set a VERY straight edge across both cylinders and clamp it down. I then measure the top of the cylinder mating surface down to the very edge of the piston using a dial indicator/depth gauge. I repeat the measurement at least 5 times and average the results. I am getting measurements that vary from .022 to .032 and they can vary by up to .0067 across a single piston (front to rear). (IMG:style_emoticons/default/WTF.gif) (measurements at the same spot are repeateable within less than .001) When we are trying to get these deck heights to match to within a few thousandths, I cannot see how that can be done when the piston can be off by more than 5 thousandths front to rear. Does this mean I have bent rods or misaligned wrist pin bushings? I had the entire rotating assembly balanced, so I would hope they would have caught something bent. I guess my next steps will be to shuffle the pistons around and see if the measurements follow the pistons. If they dont, I might need to move rods. Can all 4 rods be removed & replaced without splitting the case again? Stu |
stugray Deck height measurements driving me crazy Oct 14 2012, 02:06 PM
Vacca Rabite Shim the base of the cylinders.
Don't start m... Oct 14 2012, 04:28 PM
rick 918-S Just a guess but sounds like maybe collapsed regis... Oct 14 2012, 05:46 PM
Valy Are the rings on?
The pistons will rock a bit in ... Oct 14 2012, 10:26 PM
yeahmag Are you using the tool I built?
-Aaron Oct 15 2012, 11:11 AM
McMark Did you have the cylinder spigots machined? Oct 15 2012, 11:36 AM
stugray 1- Just curious, why would shims make a difference... Oct 15 2012, 01:42 PM
yeahmag The plate simply sits on top of the cylinders loca... Oct 15 2012, 02:15 PM
r_towle I measure at the side of the piston directly above... Oct 15 2012, 03:15 PM
yeahmag Rich,
I think you mean above the piston "wri... Oct 15 2012, 03:24 PM
r_towle
Rich,
I think you mean above the piston "wr... Oct 15 2012, 04:08 PM
Vacca Rabite When I did mine I measured from the exact center o... Oct 15 2012, 03:39 PM
stugray I have all of the rings on and I measure in line w... Oct 15 2012, 03:40 PM
yeahmag Do you understand how to use the tool now? If not ... Oct 15 2012, 03:45 PM
stugray
The .006 difference is across the same piston wi... Oct 15 2012, 09:19 PM
wndsrfr [quote name='stugray' date='Oct 15 201... Oct 16 2012, 11:31 AM
yeahmag Which direction are you measuring the piston? Acro... Oct 16 2012, 10:55 AM
r_towle If those measurements are at the top of the piston... Oct 16 2012, 12:59 PM
stugray
This is a vintage race engine that is carbed and... Oct 16 2012, 04:54 PM
bobhasissues
You have mentioned this cam in several of your t... Oct 17 2012, 08:03 PM
yeahmag Measure using the slot on the inner edge of each c... Oct 16 2012, 04:56 PM
stugray yeahmag,
I only see the large difference in side-... Oct 16 2012, 05:18 PM
yeahmag That stinks... Sounds like something is messed up. Oct 16 2012, 05:22 PM
r_towle Have you tried a simple feeler gauge and a straigh... Oct 16 2012, 05:25 PM
stugray
Yes and it showed a difference from side to side... Oct 16 2012, 10:22 PM
Vacca Rabite Please put up some pictures of what you are doing.... Oct 17 2012, 06:42 AM
Randal
Please put up some pictures of what you are doing... Dec 25 2012, 10:31 AM
stugray Bob - I would post a link to Jakes Type-IV store t... Oct 18 2012, 10:24 AM
Vacca Rabite
Bob - I would post a link to Jakes Type-IV store ... Oct 18 2012, 12:00 PM
stugray The cam is a: "Super 9700 Cam Kit", incl... Oct 20 2012, 08:17 PM
stugray Ok, got the new tools to do this right, and the re... Oct 22 2012, 11:16 PM
rick 918-S What happens of you swap cylinders? I would invest... Oct 23 2012, 07:03 AM
yeahmag Flip the plate end for end so the overhang "t... Oct 23 2012, 08:28 AM
Valy What is your deck height right now? You should hav... Oct 23 2012, 01:29 PM
jmalone Have you measured from the top of the problem pist... Oct 23 2012, 02:05 PM
stugray I will do the suggestions above, but for now I rep... Oct 27 2012, 12:04 PM
Joe Sharp Pull the crank and lay it on the bench with all th... Oct 27 2012, 05:00 PM
stugray Joe,
Thanks! but I was hoping to do as many s... Oct 28 2012, 11:18 AM
wndsrfr
Joe,
Thanks! but I was hoping to do as many ... Oct 28 2012, 04:27 PM
stugray Not sure what this means.
I flipped the #4 Rod an... Oct 28 2012, 09:36 PM
yeahmag Did you measure the cylinder height differences wi... Oct 28 2012, 10:36 PM
stugray Yes, less than 0.001 between the two.
Stu Oct 29 2012, 07:16 AM
stugray Bump!
So the only things I can find say that ... Oct 29 2012, 09:29 PM
yeahmag I would suspect the rods first. You can snake them... Oct 30 2012, 10:00 AM
r_towle You need to open up the case and send everything t... Oct 30 2012, 10:27 AM
brant I would have a shop check the registers and also f... Oct 30 2012, 10:37 AM
Valy Measure the piston travel. If it's as expected... Oct 30 2012, 10:38 AM
yeahmag I agree in principal, but there is no reason not t... Oct 30 2012, 10:41 AM
stugray I will go over all of the suggestions above but he... Oct 30 2012, 02:34 PM
r_towle Crank was balanced at a shop? then its straight.
R... Oct 30 2012, 02:37 PM
yeahmag Actually, the rods can be in balance but different... Oct 30 2012, 02:40 PM
r_towle
Actually, the rods can be in balance but differen... Oct 30 2012, 02:44 PM
yeahmag Agreed, but the one thing I have taken to heart fr... Oct 30 2012, 02:46 PM
stugray
I would agree that the MAIN journals would need ... Oct 30 2012, 04:53 PM
stugray ok, latest update.
I took all four rods off witho... Nov 3 2012, 09:57 PM
yeahmag RIMCO or EMS can do it. Nov 3 2012, 10:57 PM
Valy You should have measure the piston travel before t... Nov 4 2012, 10:45 AM
stugray Ok, talked to a two local machine shops who claim ... Nov 7 2012, 10:17 PM
McMark Remember that each case half must have matching re... Nov 8 2012, 09:58 AM
stugray Thanks - he said that he would machine all four re... Nov 8 2012, 12:58 PM
Racer Chris
...
If the #1 & 2 side is perfect, is there a... Nov 8 2012, 04:20 PM
Harpo
Thanks - he said that he would machine all four r... Nov 8 2012, 04:33 PM
stugray David - Sorry, but what is "EMS"?
I kno... Nov 8 2012, 06:28 PM
Dr Evil EBS, not EMS. Engine Builder's Supply in Spark... Nov 8 2012, 06:41 PM
RobW Any news or update? Dec 25 2012, 06:59 AM
stugray I had the cases decked and did another measurement... Dec 25 2012, 01:35 PM![]() ![]() |
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