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Rod clearance again, (got my dial bore gage)

Posted By: Moparnut426

Rod clearance again, (got my dial bore gage) - 02/18/09 01:01 AM

So I got my dial bore gage and I miked my crank, zeroed my dial bore gage, and measured my rod with bearing in and I have .002 on the button. My question is do I have to measure each rod with each bearing because I am leaving a very tiny mark on the bearing from the dial bore gage. I cant feel it with a cotton glove on. It this bearing shot, or can I use it still? Am I being too anal about the marks?

Thanks

Kasey
Posted By: Anonymous

Re: Rod clearance again, (got my dial bore gage) - 02/18/09 01:08 AM

the proper way is to measure each journal and each bearing.
don't worry about the little scratch, it'll have no effect.
looks like it's coming along great.
Posted By: Moparnut426

Re: Rod clearance again, (got my dial bore gage) - 02/18/09 01:16 AM

As far as my mains, What should they be, and Im having it line hones so I should wait till its done correct? Or can I use a "book" spec, and measure the cran main the same way?

Thanks Dan the Man!!

Kasey
Posted By: Acme Rocket

Re: Rod clearance again, (got my dial bore gage) - 02/18/09 01:29 AM

I usually check 1 rod and 1 main. But i also check all the housing bores main and rods and mike all journals. I also mike each bearing with a bearing mike. You should check the housing bores on the mains after you get it back from your shop. Sometimes it can be very tricky keeping all the housing bores the same size. I have never worried about the small scratch. Hope this helps
Posted By: Cab_Burge

Re: Rod clearance again, (got my dial bore gage) - 02/18/09 02:55 AM

You should be able to tell your machine shop that is doing the align hone what size you want it to end up being, on the big side of the factory specs or the small size. Ask them about that as it does have an effect on how much main bearing clearnances you end up with. I would take the crank to the machine shop and have THEM measure it with THIER micrometers and then decide on what size the main bores should end up at so you get the clearnances you want, take the main bearing with you also if you have them, if you don't have them now get them before having the work done. I measure every rod and main bearing torqued up and write them down as soon as I'm done measuring each one, I also maesure every rod and main bearing surface on the crankshaft and write them down so I can do the math to see what the actual clearnances are I'm a firm beleiver in having the clearances on the loose side instead of the tight side, .002 to .003 on the rod bearings using steel rods and .025 to .035 on the mains with stock type main caps
Posted By: jamesc

Re: Rod clearance again, (got my dial bore gage) - 02/18/09 02:59 AM

Quote:

.025 to .035 on the mains with stock type main caps

Posted By: Sport440

Re: Rod clearance again, (got my dial bore gage) - 02/18/09 03:05 AM

Quote:

Quote:

.025 to .035 on the mains with stock type main caps






Its what them truck bearings call for. mike
Posted By: Moparnut426

Re: Rod clearance again, (got my dial bore gage) - 02/18/09 03:44 AM

Quote:

You should be able to tell your machine shop that is doing the align hone what size you want it to end up being, on the big side of the factory specs or the small size. Ask them about that as it does have an effect on how much main bearing clearnances you end up with. I would take the crank to the machine shop and have THEM measure it with THIER micrometers and then decide on what size the main bores should end up at so you get the clearnances you want, take the main bearing with you also if you have them, if you don't have them now get them before having the work done. I measure every rod and main bearing torqued up and write them down as soon as I'm done measuring each one, I also maesure every rod and main bearing surface on the crankshaft and write them down so I can do the math to see what the actual clearnances are I'm a firm beleiver in having the clearances on the loose side instead of the tight side, .002 to .003 on the rod bearings using steel rods and .025 to .035 on the mains with stock type main caps



Oh Im definatly going to have the shop check it out, but Im one of those guys that wants to check everything my self, I know im not a pro builder, but piece of mind goes a long ways when my foot is going through the floor on this puppy.

I measured them all individually and #3 is a bit tight at .0016, #6 and #7 are both at .0018, All the rest measure from .002 to .0021. Im going to have Kecks machine in Iowa do the work, Im just curious.
It doesnt help that I used to be a machinist, and took many night engine machine classes in college.


Kasey
Posted By: Cab_Burge

Re: Rod clearance again, (got my dial bore gage) - 02/18/09 04:03 AM

Quote:

Quote:

Quote:

.025 to .035 on the mains with stock type main caps






Its what them truck bearings call for. mike

I don't really know or care what they call for All I know is what I end up with I wish that I could get a little less sometimes but having to much clearnance is way better than having to little, like a lot of things in life
Posted By: jamesc

Re: Rod clearance again, (got my dial bore gage) - 02/18/09 05:12 AM

comon Cab where's your sense of humor i knew what you meant
Posted By: Sport440

Re: Rod clearance again, (got my dial bore gage) - 02/18/09 05:48 AM

Quote:

comon Cab where's your sense of humor i knew what you meant




I knew what you meant too It was just a decible infraction on the mains that we were funning you about.

Dont mind me though Cab, You just keep up your good work. You relentlessly help tons of people around here.
Posted By: Cab_Burge

Re: Rod clearance again, (got my dial bore gage) - 02/18/09 06:58 AM

Quote:

Quote:

comon Cab where's your sense of humor i knew what you meant




I knew what you meant too It was just a decible infraction on the mains that we were funning you about.

Dont mind me though Cab, You just keep up your good work. You relentlessly help tons of people around here.

Oops, I didn't catch the decimal error on the mains, nobody wants twenty five thousands bearing clearnances, even the top fuel or Harley guys
Posted By: 69Cuda340S

Re: Rod clearance again, (got my dial bore gage) - 02/18/09 02:16 PM

Quote:

Oh Im definatly going to have the shop check it out, but Im one of those guys that wants to check everything my self, I know im not a pro builder, but piece of mind goes a long ways when my foot is going through the floor on this puppy.



That is the only way to go, check it all yourself. Check the main and crank journals for taper and out of round too. My crank had .003" run out when measured at the #3 main bearing and some clearances were too tight. Ended up turning the brand new crank 10/10 to get it right.
Posted By: maximum entropy

Re: Rod clearance again, (got my dial bore gage) - 02/18/09 05:09 PM

Quote:

the proper way is to measure each journal and each bearing.
don't worry about the little scratch, it'll have no effect.
looks like it's coming along great.

Posted By: PS Arrow

Re: Rod clearance again, (got my dial bore gage) - 02/18/09 08:48 PM

Quote:

Quote:

comon Cab where's your sense of humor i knew what you meant




I knew what you meant too It was just a decible infraction on the mains that we were funning you about.

Dont mind me though Cab, You just keep up your good work. You relentlessly help tons of people around here.



Decible infraction??? Was Cab being too loud???
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