connecting rod bushings

L

L-head

Senior Member
I have heard that rod bushings need to be "swedged" instead of just pressed in and then honed. What type of machinery is used to do his type of work? Is it really necessary?
 
Yes , it really should, Any automotive machine worth it's salt, should have Sunnen pin hone. There is a special tool that goes in the mandrel that will swedge the bushings before honeing them. Walt
 
I've put together a bunch of engines and have changed very few rod bushings. They don't wear out very often. Check em first, very few shops can do it right.
 
Original FORD replacement bushings are steel-backed and a ***** to press in. They are good-to-go as installed and honed.
 
I would just add this here, while I understand "reasonably-loose" pins (generally speaking) will not be an issue in most cases, it is really in the customer's best interest to start "new", as in all clearances. We like to see between .0005" and .0007" on both the rods and the pistons. Full race units slightly more.

The correct procedure installing the bushings, like mentioned above, is "burnish" the new bushings, then hone to size. We're not talkng "steel-backed", different rules for these.

When we actually install the bushings we heat the pin end of the rod, this eases the bushings in place without "peeling" them off. This part of the procedure is the same for the "steel-backed" pieces. We have a dedicated rod-heater and can control the temps, we install pressed wrist pins using this same method. Even though they are "pressed", they are pushed in by hand!

(Add) John, using the rod heater and controlling the temps makes it much easier installing the "steel-back" pieces.

Thanks, Gary in N.Y.

P.S. In the 2 photo's below, showing a "used" 8BA rod, you can see the wear difference between the vertical and horizontal clearance AND the actual total amount between the bushing and the pin. The "0" on the guage would represent the real pin diameter, .750". This wear is from normal use and is inherent in all bushed rods, Flatheads or otherwise! This particular rod shows over .0015" vertically and over .0012" horizontally. This is simply too loose on a rebuilt Flathead unit.
 

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i agree,too loose.ron is correct.many shops dont do it right.in the right hans they can b right.u need to ck every thing .if you r rely on some one else u need some measuring tools.or have the guy show u but those machinist can b so defenseive.
 
jake197000 said:
i agree,too loose.ron is correct.many shops dont do it right.in the right hans they can b right.u need to ck every thing .if you r rely on some one else u need some measuring tools.or have the guy show u but those machinist can b so defenseive.
Click to expand...

Gish Jake, your texting. How old are you?
 
Hi guy's, just corrected the horizontal and vertical numbers in the my above post.

Thanks, Gary in N.Y.

P.S. The majority of the wear will be in the vertical position, not the horizontal. This is inherent on just about all bushed rods.
 
Just curious, How do tou know .oo15 is too much? It doesn't make any noise.
Who makes the rules here?
 
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