Crank Journal / Throw sizes (for bearings)

[l0nestar]

I got my crank back from being collared and measured the crank journals and throws, I can't seem to find any information on the specs for the throws. Crank was never turned,re-ground, or micro-polished. Is everything within tolerance?

Everything was measured with a set of Starett calipers, but in Inches. I used the program Convert from Josh Madison http://joshmadison.com/software/convert/ It is free and I _HIGHLY_ recommend it to anyone.

Thanks

Crank Journals:1 2.1636" 54.95544 mm2 2.1640" 54.96560 mm3 2.1638" 54.96052 mm4 2.1634" 54.95036 mm5 2.1632" 54.94528 mm6 2.1633" 54.94782 mm7 2.1632" 54.94528 mmAverage:2.1635" 54.9529 mm

Throws:1 2.8884" 73.36536 mm2 2.8881" 73.35774 mm3 2.8881" 73.35774 mm4 2.8881" 73.35774 mm5 2.8881" 73.35774 mm6 2.8882" 73.36028 mmAverage:2.88167" 73.35944 mm
Modified by l0nestar at 2:37 PM 2/12/2007

[Sil240]

Take a look in the FSM,It might say, if not I know the bearings go by color code or something. You can google or something to find out what the sizes are.

[l0nestar]

I looked at the FSM (Pages EN-217 - 220) but it did not say for the throws. Where do you find the color code? Is it on the backing to the bearing?

The Pin Grade on my crank is a grade 1 if that helps.

[Sil240]

My machinist told me.

Yeah its either color codes or numbers or a combination of both.I can't remember, its been like a year and a half since i had it done.

[RB_Dreamin]

Everything was measured with a set of Starett calipers, but in Inches. I used the program Convert from Josh Madison http://joshmadison.com/software/convert/ It is free and I _HIGHLY_ recommend it to anyone.

are you serious?

[l0nestar]

... yes? Am I serious about which part? The measuring or the program?

[l0nestar]

If you mean, "Are you serious that you measured it in inches" then yes, because that is all that the shop uses. It should not matter if you measure in inches or mm, as long as you have enough precision, it won't matter. I could have measured it by furlongs or nanometers, as long as there is enough precision, it won't matter. Look at the first post, the numbers on the left are what I received from them (2.16xx") Ten-Thousands precision in Inches, I converted to (54.95xxxx mm) Hundred-Thousandth of a mm precision. I think that should be fine...

[l0nestar]

But if you are asking me if I am serious about the program from Josh Madison, then yes, it is a wonderful free conversion program and I suggest everyone to check it out!

[Sil240]

But if you are asking me if I am serious about the program from Josh Madison, then yes, it is a wonderful free conversion program and I suggest everyone to check it out!

My machinist did the same thing.Measured everything in inches too!!!My guy usually builds like big block etc I guess....

I use http://www.onlineconversion.comThey have everything.

[002-M-P]

Your average for your throws is wrong...its smaller than your smallest measurement, just an fyi

And yes, Convert is an awesome program...I use it alot. Otherwise I would use http://www.convert-me.com

[l0nestar]

Sil240,

Yeah, the guy is used to building big cube (1000+ HP) V8's and Diesels. He did know some about small engines, but yeah, not his bag. Did your measurements look anything like mine? All I want to know is, are they in factory spec? I need to know if I order standard or over / under sized bearings!

[l0nestar]

002-M-P,

Convert is an awesome program. I had used it at University and at my previous job. Thanks for the update on my math I fixed it.

[Sil240]

Sil240,

Yeah, the guy is used to building big cube (1000+ HP) V8's and Diesels. He did know some about small engines, but yeah, not his bag. Did your measurements look anything like mine? All I want to know is, are they in factory spec? I need to know if I order standard or over / under sized bearings!

Tell you the truth I don't remember.I have paper work at home I can look at.But I don't think it was anything specific.I'll take a look for you.

I know there's some other guys who rebuilt their motors also.See if they remember.

I think I remeber the Bearing being REALLY close to L series bearing except the tang being in the wrong place.Look into that.I remember I had to wait a long time to find my bearings.

I got mine from B&E customs.There's a guy in Australia who had them for a great price but I didnt' want to wait.

[l0nestar]

Well, I can get the standard size bearings shipped from FLA tonight / tomorrow. I just need to know if mine are 'in spec' or not, and where to find out what 'grade' bearings I have. That's it!

[l0nestar]

... Anybody?

[RB_Dreamin]

... Anybody?

the reason i asked if you were serious is because you don't need to download a tool to multiply a number by 25.4. google, windows calculator, excel, anything can do it.

what reassurance are you trying to get here with your clearances? are you only ordering main bearings? where are your specs for your rods? rod journals? where are your ID measurements for your mains? how do you expect to know the bearing thickness you need without having the ID measurement?

other than that, your measurements look fine

[eh?]

http://s92978298.onlinehome.us/crank.htm

http://s92978298.onlinehome.us/tech.htm

[Darius]

You must mike your rod ends with the caps torqued down, but without your bearings installed. You already have the outside diameter of each rod journal on the crank. Subtract the journal diameter from the large-end rod inside diameter to find out your bearing+oil film thickness. Subtract out the oil thickness allowed by the FSM and you will be left with the bearing thickness required. Compare the bearing thickness to the chart listed in the FSM and you will be able to select STD, oversized or undersized. I highly doubt that you will have anything but STD bearings, but you have to verify this.

On the crank main journals, simply use plastiguage and torque down the girdle. Remove the girdle again and measure to your best approximation, the width of the plastiguage.

After typing this, I'm basically regurgitating what RB_Dreamin' posted a couple posts up the page...I'm with him

There is no black magic in converting inches to mm. There are 25.40mm in an inch. If you know what significant figures are, there are only 4 sig figs in the inch measurements so you can only approximate to 4 sig figs on your mm measurements. Therefore, round your last number on the conversion up or down.