Low buck 440 build, bad turn

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RGAZ

Diehard
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Ok so against my better judgement I picked up a disassembled 71 440 from a local guy. He appeared to be organized but I am guessing not now.

So I am assembling the bottom end after cleaning honing etc. block is marked underside and the old bearings he left behind confirm 0.001 underside. I picked up some king bearings and when I torque to spec they lock the crank. So I whip out the Plastigage and there is like no clearance. So I try a different piston position and get the same. I put in the old bearings and same result (my uh oh moment).

So now I think he may have mixed up the caps. That or the rods are warped. Here come the questions:

Is there a way to re-match the caps?
Keeping this low buck, should I get some cheap rods and move on? What are the cheapest option?
Or do I need to bail and take it to a machine shop and blow my budget?

Thoughts?
RGAZ
 
With stock rods……..If the rod caps are on the wrong rods, it’s usually fairly obvious by looking at the way the chamfers meet at the parting line.
After matching the caps to the rods based on the chamfers, then torque to spec and measure with a bore gauge to verify sizing and roundness.

If the crank sizing is oddball, just have it ground to a normal size.

My experience has been that engines aren’t very forgiving of crank bearing “issues”.
You want it to be as right as possible.
 
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Ok so against my better judgement I picked up a disassembled 71 440 from a local guy. He appeared to be organized but I am guessing not now.

So I am assembling the bottom end after cleaning honing etc. block is marked underside and the old bearings he left behind confirm 0.001 underside. I picked up some king bearings and when I torque to spec they lock the crank. So I whip out the Plastigage and there is like no clearance. So I try a different piston position and get the same. I put in the old bearings and same result (my uh oh moment).

So now I think he may have mixed up the caps. That or the rods are warped. Here come the questions:

Is there a way to re-match the caps?
Keeping this low buck, should I get some cheap rods and move on? What are the cheapest option?
Or do I need to bail and take it to a machine shop and blow my budget?

Thoughts?
RGAZ

If you are lucky. the person who disassembled the engine may have used punch marks, letters or numbers to locate the caps proper position.
 
He did punch the caps but not the rod, he did it on the bottom instead of the side like I’m used to.

Crank shows 2.370” but I don’t love my micrometer.
 
You need to see if you rod journals are round and what size they are, you could have the caps backwards and you can find where they fit.
 
You need to see if you rod journals are round and what size they are, you could have the caps backwards and you can find where they fit.

Is there a sure fire way to ensure they are not “backwards”? Do the tangs go on the same side or opposite?

Matching the chamfers is not as obvious as I would hope. My manual is not much help at this level of detail.
 
Tangs on the same side.

“Matching the chamfers is not as obvious as I would hope.”

That’s where the bore gauge comes in.
You do your best to match the caps to the rods, torque to spec, and measure.
It’s unlikely you’d get all 8 wrong by matching them up.
Any that don’t measure good get some mixing and matching until they measure good.

If you don’t have a dial bore gauge for this, frankly even if they were easily identified/matched by the chamfers…….. you’re guessing if they’re round and to size.
 
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Have a bore gauge and measured with bearings installed and the numbers did not make sense. It would suggest the bearing needs to be much thinner which is not possible. They could be out of round so it would mean a set of rods needed.

Bummer again.
 
Have a bore gauge and measured with bearings installed and the numbers did not make sense. It would suggest the bearing needs to be much thinner which is not possible. They could be out of round so it would mean a set of rods needed.

Bummer again.
My suggestion is to measure the rods without the bearings.
Make sure they are round and to size on their own first.
This is the check to make sure the caps are on the correct rod.
Torqued to spec obviously.

If the bearings are for an undersized crank, they “should” be marked as such.
 
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2.370” would be .005” under.
I doubt you’ll find bearings for that.

The Clevite bearing book shows the std shaft diameter for the rod journals should be 2.3740-2.3750”.
 
My suggestion is to measure the rods without the bearings.
Make sure they are round and to size in their own first.
This is the check to make sure the caps are on the correct rod.
Torqued to spec obviously.

If the bearings are for an undersized crank, they “should” be marked as such.
Ok, I’ll get on that. Yes, the bearings I removed are clevite 0.001 US marked and the new King ones are 0.001 US marked.

I truly think I have the caps mixed up. Maybe by checking each bore I can match them up or at least confirm the rods are out of round and therefore fubar.

Good advice guys.
 

Ok, I’ll get on that. Yes, the bearings I removed are clevite 0.001 US marked and the new King ones are 0.001 US marked.

I truly think I have the caps mixed up. Maybe by checking each bore I can match them up or at least confirm the rods are out of round and therefore fubar.

Good advice guys.
I probably have a spare set of 440 rods plus a set of NOS 440 rods. I could probably come over and tell you what is going on.
 
I confirmed that the caps were mixed up. I setup a method to check every cap against each rod. I used a bore gauge and three points of checking. It was pretty obvious with that data how to match. Here is my basic process for posterity:

Clamp the rod in a soft jaw vice.
Clean all parts. Apply each cap with lube. Torque to 45 (no need to stretch the bolt). Lay straight edge on each side of the opening face. If the two halves don’t match both chamfer and flat, it’s not close. Otherwise, using bore gauge set to 2.500” check for zero vertical and 45 degree each way. All three numbers should be the same and close to zero. Be sure to rock the gauge properly to get a good reading. Repeat for each cap and choose the best match. Replace all Rod bolts when done. Pics:
IMG_3053.jpeg
IMG_3054.jpeg
IMG_3055.jpeg


I also reverified the bore gauge with the micrometer noted in the pics because some numbers were way off.

Hope this helps others.
RGAZ
 
For the record:
Cap 1 was on 8
Cap 2 was on 2
Cap 3 was on 3
Cap 4 was on 4
Cap 5 was on 5
Cap 6 was on 1
Cap 7 was on 6
Cap 8 was on 7

So they were half right. All my fit work was done with piston 1 and 6 so it all makes sense now!!

RGAZ
 
For the record:
Cap 1 was on 8
Cap 2 was on 2
Cap 3 was on 3
Cap 4 was on 4
Cap 5 was on 5
Cap 6 was on 1
Cap 7 was on 6
Cap 8 was on 7

So they were half right. All my fit work was done with piston 1 and 6 so it all makes sense now!!

RGAZ
Nice work. In my experience with the older motors, The rods and caps were both numbered the same, so pretty hard to mess up.
 
The rods did not have any numbers on them. That’s the problem that required this process. Previous owner marked rods with paint pen and clearly messed up.

Caps are the only thing marked and only on the bottom.
 
I like to restamp fresh numbers onto the rod and cap if what’s already on them isn’t clearly identifiable(or are “symbols” like I’ve seen on a few sets.

I want to be able to have the rods and caps be separated and mixed up on the bench, and have it be basically zero effort to match them back up.
 
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