OK, Here's a New One.........

After all the repairs to the heads, block and stuff after my latest blow-up (self induced, owned it), I am assembling the motor and checking everything, I mean everything.

Poured the cylinder, 10.4 or 10.7 compression depending on which gasket, Went to put in the pushrods and the replacement tubes that were installed don't have enough clearance for the exhaust pushrod. How thin can I grind that tube and what would be the best tool to use?

Thanks again, hope someday to put some good news up on this message board, you guys have helped a lot.

Scott

 

The tube is .725 OD and .625 ID pressed into the Veney head and exposed to the intake port, how thin can I grind for pushrod clearance?

 

Scott,
How many threads are showing on the adjusters. Especially on the exhausts. The more you have, the further the centerline of the adjuster ball moves away from the center of the tube, pushing the pushrod into the tube. Also, what kind of pushrods, if straightwall 7/16th you may have to got to the elliptical, 7/16th to 3/8th. If those measurements are right, that's a pretty thick tube, but I wouldn't take more than .025-.030" just to be safe.

 

I have 4 to 5 threads showing. This motor went together before the tubes were replaced. The interference is on the intake side. The pushrods were in this motor and fit (barely).

Any ideas on how thin I can cut the tube?

 

Height on lifters will also make difference here.

 

I wouldn't grind the tubes
find the right pushrods 4-5 threads are a bunch
do you have a 5/16 ball or 7/16 adjuster
if it is 5/16 find a ball bearing that size and measure the length with it in and let me know i will look and see what all lengths i have laying around
sounds like you need longer ones 7/16-3/8 taper both ends works good

 

ok heres a knew one

You may need longer pushrods.

 

Pushrod Clearance

I had the same problem on one motor. I also had about 5 threads showing under the rocker arm. Same binding problem. I ordered longer pushrods that had less than one thread showing solved the problem. That being said, I run AJ2 fuel heads and the pushrod tubes that run through the intake ports are made of brass and are probably .020 wall, definitely not the thicker wall that you have now. My pushrods are so long that you have to completely retract the adjuster ball to even get the pushrod to go under the rocker. Works very well now, no issues. Oils properly too, which the shorter pushrods and more adjuster thread did not oil properly.
Just my $.02

 

Apologies for my brain fart, was thinking the tubes were .100" thick, realized they are only .050", not sure I would take much of any off of the tubes. Like has been said above, longer pushrods to minimize the amount of threads showing is about the only cure. What that is doing is minimizing the amount of side to side travel (from intake side to exhaust side, looking from the front of the engine to #1 rockers) of the adjuster ball as the rocker moves through its travel cycle. The further the adjuster is extended, the further away the adjuster ball is from the center of the tube.

 

BAE so different but the tubes do the same thing if you uprate the rocker gear, iv just dented the tubes where need be and live with the fact they rub a but i think most guys stuff is the same from what iv seen tbh if you let them hit they will dent the tube themselves...done that too

 

I do have the 5/16 ball. I'll be back on the motor tomorrow and will let everybody know what simulating a longer pushrod does.

Thanks for all the replies
Scott

 

Today's word "Amazingly Close"

After a very responsive machinist asked advice from Hemi experts that do Hemis all day and all night at the races this weekend (thanks by the way), he made a house call to measure and find the solution for the new pushrod tube interference problem. After moving the rockers as suggested, the tubes clear, they are "Amazingly Close". I will touch the bottom edges of the tube with a reamer bit jut to get a few thousandths.
Thanks for all the help and replies, I had some slightly longer pushrods in the bin as well, that helped too.

Maybe I'll post some good news after the weekend, fingers crossed.