Idler arms early a vs 67 up cars

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stretch

I cut my cars!
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I am considering modifing my 65 K-frame to accept the later model idler arm so I can take advantage of the added frame mount and a through bolt at the frame pivot. Do any of you know if the mount end is all that changed? Is the taper at the center link the same? Is the overall casting dimensions the same making the mount the only difference? Have any of you made a similar modification?
 
I have heard of people modifying a 67 K-frame to take the 68-up idler, but there was a lot of skepticism on the forum as to whether it could be done accurately enough to maintain perfect geometry. The response was, with plenty of 68-72 A-body K-frames available, why not just swap? I don't know how different the 65 K-frame might be, dimensionally, but if the idler is the same exact unit as the 67 idler, you would think it could be done. I am not sure if it is worth it, however. The bayonet-mount idler is perfectly adequate so long as it remains sufficiently tight. The problems occur when the nut is too loose and it can move around, destroying the tapered hole and ruining the K-frame for all intents and purposes. Even in these cases the idler arm itself is usually fine — it's not the problem.
 
67 can be modded to 68-72 if you make a geometry correct accurate jig made off a 68-72 K frame. Pix below are A 67 slant 6 K that using a jig I made to mod it into a V8, and another jig into a 68-72 K frame. There are more slanty Ks than V8 Ks. If you have a rotted or bent V8 K frame and a solid , straight slant 6 K frame, it makes a lot of sense to convert it. The idler arm mount and RH V8 mount for the converted slanty K came from a V8 K that was rotted out in the middle. Motor mount is done. I still need to weld the 68 up idler mount in, and unbolt the jig. Then sandblast and paint it. The jig holes are drilled and welded to steel tubes that accurately locate the bolts so there is no slop in it.

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67 can be modded to 68-72 if you make a geometry correct accurate jig made off a 68-72 K frame. Pix below are A 67 slant 6 K that using a jig I made to mod it into a V8, and another jig into a 68-72 K frame. There are more slanty Ks than V8 Ks. If you have a rotted or bent V8 K frame and a solid , straight slant 6 K frame, it makes a lot of sense to convert it. The idler arm mount and RH V8 mount for the converted slanty K came from a V8 K that was rotted out in the middle. Motor mount is done. I still need to weld the 68 up idler mount in, and unbolt the jig. Then sandblast and paint it. The jig holes are drilled and welded to steel tubes that accurately locate the bolts so there is no slop in it.

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That jig off the steering box mount is sheer genius.

That said.......If you read the MP suspension book on how to set up the Mopar front suspension, it becomes clear that getting it "close" in regards to the idler arm angle is really "good enough". The book shows how to get the arm in exactly the correct position by filing the top and bottom holes, so as long as the bracket is in the ballpark, you got it licked.

Of course, when you have a really simple jig like that, it makes it pretty easy to get it dead on, and there's certainly nothing wrong with that.

ALL THAT said, Is this really a mod that you NEED? "I" have not witnessed ANY failures of early A body idler arm brackets. I'm sure it's happened, but it just must not be that frequent. But that genius jig even makes me think about it.
 
Thanks rusty.
I had done the motor mount jig off a 68-72 V8 K awhile ago. Worked great as you bolt the V8 mount to the jig cut the slanty motor mount off, and grind smooth. Then using K frame shoulder bolts it centers it in place to weld it. This can also be used to check a K frame for straightness, and to seam weld a K frame on the welding table without wattage.

I had been brain storming the other jig for the idler arm for awhile. Then over new years holiday my son and I were separating out a huge box of automotive hardware. I found the metal tube spacers in the box, and knew right then I was going to use them to make the idler arm jig so I set them aside. The rest is history.

Heres a different pic of idler and jig, and 2 more of K frame jig.

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I have the bracket from later model K to put on my 67 K if I ever need it. No more than the car is driven, the 67 idler may last longer than I will.
 
Ok, now back to the original posters question? can you use a 68+ idler on a 65?


Alan
 
I would imagine you would need to use the 68 idler and pitman arms as a matched set. A 68-72 idler bracket. Not sure where these would position the center link. You would want to change the pitman and idler as a set. If theres a length difference between the 68-72 idler and the early A pitman arm, and you dont do this, it will change the Ackerman angle when steering the car.
 
Or, if you are having trouble finding them, I have all of them ++ Brand New ++
The 1962 - 1966 "A" Idler Arm
The 1967 -- one year only -- "A" Idler Arm
And, of course, the 1968 - 1972 "A" Idler Arm....
All U.S.A. made !!!! P.M. me, if you need or want....
 
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