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stugray |
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#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 |
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stugray |
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#2
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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 ![]() |
Joe,
Thanks! but I was hoping to do as many steps as possible without splitting the case again. I thought about a similar step that I should have done before using the rods. You could align and clamp all four rods into a vise from the crank end. Then you should be able to get a wrist pin to slide through all four rods with a minimum of wiggling things a bit ;-) Didnt do that, but maybe next time. This would tell you if all wrist pin bushings are co-linear. However, does anyone see a problem with my huge range of deck heights? Cyl #1: = 35.0 Cyl #2: = 32.75 Cyl #3: = 30.75 Cyl #4: = 25.5 I do not see how I can buy shims to make all of those equal while keeping the deck on each head even for mating to the heads. Stu |
wndsrfr |
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#3
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Senior Member ![]() ![]() ![]() Group: Members Posts: 1,446 Joined: 30-April 09 From: Rescue, Virginia Member No.: 10,318 Region Association: MidAtlantic Region ![]() ![]() |
Joe, Thanks! but I was hoping to do as many steps as possible without splitting the case again. I thought about a similar step that I should have done before using the rods. You could align and clamp all four rods into a vise from the crank end. Then you should be able to get a wrist pin to slide through all four rods with a minimum of wiggling things a bit ;-) Didnt do that, but maybe next time. This would tell you if all wrist pin bushings are co-linear. However, does anyone see a problem with my huge range of deck heights? Cyl #1: = 35.0 Cyl #2: = 32.75 Cyl #3: = 30.75 Cyl #4: = 25.5 I do not see how I can buy shims to make all of those equal while keeping the deck on each head even for mating to the heads. Stu Hmmm......#'s 1&3 are high relative to #'s 2&4.....seems like possibly your crank is not centered relative to the registers beneath the cylinders. Is it possible that your engine is composed of two case halves that don't match up? Like if it was put together from two different engines?? Just trying to think out of the box..... |
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