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Cold Leak down test

 
Old 02-23-2019, 12:18 PM
  #16  
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BTW, leakdown tests are a differential measure. Cyl 8 indicates your highest number being 88PSI, so assuming you put 100PSI in as supply pressure. Usually reported as 88/100, 30/100, 45/100, 70/100. Also important is how big the supply orifice is so that we know there's enough air flow to pressurize to cyl. It looks like you had plenty of flow, as a lot of the numbers are really bad. As mentioned, what's just as important is where you hear the leaking air going. If coming out the crankcase breather, that is rings. If coming out the exh pipe, that is exh valve, if from the intake, that's intake valve. Better to know what you know before tearing things apart.
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Old 02-23-2019, 02:12 PM
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I used a Snap On tester that showed percentage. I was using 80 to 90 psi as my source. Most of the air is escaping from the crank case. Cylinder eight had more blow by on the intake then the others. I think I’ve got all the information I can garner at this point. Trying to get this crank bolt out after building a crank lock Tool is proving to be a challenge.

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Old 02-23-2019, 06:39 PM
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use an 1/2 inch airgun with 120PSI the 27mm socket,
it will come off before can type thanks
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Old 02-23-2019, 10:00 PM
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Well, I finally got the cams out. I only had to easy out two bolts. The best so far. Had the original oil galley plugs. I think the cams look good. No evidence of odd wear on the lobes and there was a little bit of discoloration on a couple of the bearing services but no galling at all. I just got them all packed up now to figure out a good way to store the lifters. I guess they really don’t need to be matched to the cylinder, but I am a little OCD.


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Old 02-24-2019, 02:27 AM
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Originally Posted by firemn131 View Post
Well, I finally got the cams out. I only had to easy out two bolts. The best so far. Had the original oil galley plugs. I think the cams look good. No evidence of odd wear on the lobes and there was a little bit of discoloration on a couple of the bearing services but no galling at all. I just got them all packed up now to figure out a good way to store the lifters. I guess they really don’t need to be matched to the cylinder, but I am a little OCD.


Yes, keep each lifter with each lobe...do not mix them up. Lifters wear into cam lobes.

I mark them with a paint marker, after cleaning the tops. 1I1 (#1 cylinder, Intake, 1st lifter to front), 1I2, (#1 cylinder, Intake, 2nd lifter frim front) 1E1 1E2....and so on for all 8 cylinders.

Put them upright in a flat box on a few of those blue paper shop towels that you can buy almost anywhere (Costco, Walmart, Home Depot....they virtually have no.lint.) They will drain some. Leave them alone. When it is time to re-install them, wipe them off with more blue paper towels and liberally apply some assembly lube to the sides and the top. (Torco is the absolute best.) Don't forget to put a dab of assembly lube on the tip of the valve stems.


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