K1 rod install

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   I need help. I'm assembling my 401 using the K1 rods, but I can''t seem to get clarity on which way the offset on the big end is suppose to face. Where two rods share the same journal, are they suppose to be offset toward each other? Said a different way, the "bump" out on the one side of the big end of the rod faces away...toward the throw, and the narrower parts of the two rods sharing the journal face each other? 

The K1 direction don't clarify and the TSM is no help. Any help would be appreciated. It's my first rebuild (though plenty of experience with motorcycles). 

Many thanks. 

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Steeno Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Apprentice Joined: Aug/24/2011 Location: Ottawa/Canada Status: Offline Points: 88	Post Options Post Reply Quote Steeno Report Post Thanks(0) Quote Reply Topic: K1 rod install Posted: Aug/04/2012 at 7:02am
	I need help. I'm assembling my 401 using the K1 rods, but I can''t seem to get clarity on which way the offset on the big end is suppose to face. Where two rods share the same journal, are they suppose to be offset toward each other? Said a different way, the "bump" out on the one side of the big end of the rod faces away...toward the throw, and the narrower parts of the two rods sharing the journal face each other? The K1 direction don't clarify and the TSM is no help. Any help would be appreciated. It's my first rebuild (though plenty of experience with motorcycles). Many thanks.

SKeown Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Addicted Joined: Jul/30/2009 Location: Texas Status: Offline Points: 3085	Post Options Post Reply Quote SKeown Report Post Thanks(0) Quote Reply Posted: Aug/04/2012 at 8:06am
	They offset away from each other with the chamfored sides toward the crank's radious. You'll see the rods centered on the wristpins when correct. SKeown

Steeno Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Apprentice Joined: Aug/24/2011 Location: Ottawa/Canada Status: Offline Points: 88	Post Options Post Reply Quote Steeno Report Post Thanks(0) Quote Reply Posted: Aug/04/2012 at 9:17am
	Okay, thanks SK I'll just restate so there is no question or confusion: with the big rod end offsets away from each other on the shared journal as you mentioned, one of the effects of this is that the rod beams of the two on the shared journal are closest to each other in terms of being "side by side" so to speak. Correct? I will test the rod orientation in the bores without the pistons to help confirm this...I should be able to eyeball it, I suppose. Knowing this is important when I'm installing the pistons onto the rod, correct? That is, piston orientation (valve reliefs to the top toward the intake side) must be established along with the how the big end of the rod is placed on the journal. Apologies if this is obvious or repetitive, but I don't want to assume too much. I think I'm clear on it but want to be doubly sure. As well, my membership doesn't yet allow posting pictures which might make it easier than describing with words. Many thanks

SKeown Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Addicted Joined: Jul/30/2009 Location: Texas Status: Offline Points: 3085	Post Options Post Reply Quote SKeown Report Post Thanks(0) Quote Reply Posted: Aug/04/2012 at 12:00pm
	Looking at the bearing bore of the rods you'll see one side chamfored, that's there to clear the radious on each side of the crank's journal. The actual beams of the rods when installed will be seperated the MOST. SKeown

Steeno Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Apprentice Joined: Aug/24/2011 Location: Ottawa/Canada Status: Offline Points: 88	Post Options Post Reply Quote Steeno Report Post Thanks(0) Quote Reply Posted: Aug/04/2012 at 6:49pm
	Thanks SK Got it. It's all together now....and appears to be correct :))

Steeno Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Apprentice Joined: Aug/24/2011 Location: Ottawa/Canada Status: Offline Points: 88	Post Options Post Reply Quote Steeno Report Post Thanks(0) Quote Reply Posted: Aug/06/2012 at 2:35pm
	While everything appreared to look right, once I torqued the rod bolts, the crank was very hard to move. I checked and rechecked the clearances -- bearing and side -- all was good. But it looks like the K1 rods differ from the stock rods -- where the bearing is slightly smaller in width than the cap and rod where they seat, the K1 rods orient the bearing closer to the crank throw and the stock rods orient the bearing toward center of the journal leaving a space for the crank/journal radius. The stock rods also have a nice, clearly larger, chamfer where is comes against the throw. The K1 has no such bevel, both sides have a slight and equal size chamfer. The effect of all this is that the K1's clearly have some heavy interference with this radius once it is torqued. Even to the naked eye, with the rod cap off and the rod seated in the journal, the interference is clear. This is my first AMC rebuild, so I've spent most of the day, checking, rechecking trying to see if I've made a goof. I even tried the rods backwards to mimick the stock rod where there bearing is clearly spaced away from the radius on the crank. The effect of this was successful in the sense that it provided the necessary clearance I needed, but the rod was slight off center of the piston, and the bearing oiling hole faced opposite -- its suppose to be oriented to the interior of the engine etc. The crank radius is not huge -- where the finished journal meets the throw -- its a stock dimensions, and the bearings and bearing surface are in good shape. And as I said, all the clearances are dead on...it just seems like the bearing needs to be spaced away from the throw...as it is with the stock rod. I'll call K1 I suppose, but it seems pretty clear that I'm going to have to have a machine shop do some work to fit the rods -- cut a chamfer I suppose -- but that will reduce the width of the bearing. Reducing this surface area doesn't seem like a good idea. Is it possible that the bearings are unique to the rod -- that I should get K1 bearings, instead of stock??? I guess I'm naive, I really thought the K1 rods would a nice addition -- strong and with the full floater which had the added benefit I could install wrist pins without machine shop. Has anyone else had difficulty with K1 rods? Any suggestions or solutions are welcome. Thanks.

SKeown Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Addicted Joined: Jul/30/2009 Location: Texas Status: Offline Points: 3085	Post Options Post Reply Quote SKeown Report Post Thanks(0) Quote Reply Posted: Aug/06/2012 at 3:51pm
	How much rod side clearance do you have? You may have to chamfer the bearings, but first try King brand bearings from Summit. You won't need to alter the rods, you just need to get the bearings off the crank's radii. Slightly narrower bearing surface wont hurt. SKeown

addic Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Nut Joined: May/01/2008 Location: Kansas City Status: Offline Points: 370	Post Options Post Reply Quote addic Report Post Thanks(0) Quote Reply Posted: Aug/06/2012 at 4:14pm
	I also purchased K1 rods. will have to check mine
	73 401 Pierre Cardin X P1 73 401 Pierre Cardin X F3 70 X 390 4spd 69 X 401 6 spd 69 AMX 401 auto BSO 73 AMX 401 4speed pc 73 vette 427sb 5spd 73 vette convt.? 08 zx14

Steeno Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Apprentice Joined: Aug/24/2011 Location: Ottawa/Canada Status: Offline Points: 88	Post Options Post Reply Quote Steeno Report Post Thanks(0) Quote Reply Posted: Aug/06/2012 at 4:24pm
	My side clearance is fairly generous at 0.012. Seems like lots from the posts I've seen on similar topics. When I torq everything in with the bearings clear of the radius (that is, backwards, as I mentioned earlier), it's fine. I wasn't able to get through to K1 (wasn't able to wait on hold). I'll try them again tomorrow. I'll look into the King bearings from summit as well. I'm sure it wouldn't even need to get the rods chamfered...if I could get a little space between the throw and the bearing. I'll let you know what K1 says. Thanks.

SKeown Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Addicted Joined: Jul/30/2009 Location: Texas Status: Offline Points: 3085	Post Options Post Reply Quote SKeown Report Post Thanks(0) Quote Reply Posted: Aug/06/2012 at 5:55pm
	Are we talking AMC replacement rods or are you adapting Chevy rods to an AMC engine? No matter what, you dont want the bearings touching the corner radii, but .020 side clearance is common. I run .016 clearance in a 7500 RPM engine. Go to amcdragracing.org, look under "members projects" and find "reviving the wannabee", there you may find some good imfo. That was a couple of years ago, but I went back and forth with Tom (owner of K1 at the time) about something, I cain't remember what though. Check it out and let us know the outcome. SKeown Edited by SKeown - Aug/06/2012 at 6:13pm