Really stuck push rod tubes...

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pkboxer
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Really stuck push rod tubes...

Post by pkboxer »

Anyone have experience with really stubborn push rod tube removal?

These were either glued in or are welded by corrosion.

I've tried pulling them per snowbum's advice, drifting them out and even made a puller to try them. No luck...

And before someone says just leave them in and don't replace them...they really need to be replaced now. Really really.

I'm just doing to plug the tube with a rubber bung and flood them with PB blaster and let sit for week.

Anyone ever have to machine them out? Did that work out fine?
'74 - R90/6
Kurt in S.A.
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Re: Really stuck push rod tubes...

Post by Kurt in S.A. »

What about collapsing them inward? I wonder if you can get some kind of pliers with a lot of power and begin to crunch the tube in on itself...

Kurt in S.A.
the quinner
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Re: Really stuck push rod tubes...

Post by the quinner »

If they are already destroyed and being replaced...

Place the cylinder at the edge of a sturdy work bench with the base of the cylinder on the bench and the pushrod tubes hanging over the front of the bench. Either clamp the cylinder to the bench or have a stout assistant with heavy gloves help you. Find some beefy Vice-Grips and lock them securely onto the tube...just "above" the brazed on ring (a few times, I've had to literally crush the tube with the vice-grips to get the required purchase). Heat the area of the cylinder where the pushrod tube is...when it's hot enough, the pushrod tube will usually come out with some twisting on the vice-grips...REALLY stubborn tubes might require hammer blows on the vice-grips. **Keep all twisting motions or hammer blows in-line with the tube...you don't want to hog out the bore in the cylinder.

Heat and the very strong purchase on the tube are the keys.
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pkboxer
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Re: Really stuck push rod tubes...

Post by pkboxer »

Kurt, collapsing them inward is an option I was thinking of. The only reason I was hesitant, is if it doesn't work, then thought it may make it harder to machine the tube out since it'll be all buggered up.

Quinner, the vice grips and heat was the first attempt. Nothing, didn't budge.

Then I made a "puller" put a 1/2" bolt w/the head removed inside of the tube and then drilled a 1/4" hole through the tube and bolt and tightened the nut on the end of the bolt.

This pulled straight on the tube w/ a strong force. Didn't try it with heat though.

Saw other post where people warned about applying heat to the cylinder. Yes it gets hot in use but I was concerned about warping the cylinder somewhere important.
'74 - R90/6
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George Ryals
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Re: Really stuck push rod tubes...

Post by George Ryals »

Have you tried using a can of Freeze It? Liberally spray inside the tube on the head end of the cylinder. You could try a slide hammer hooked into the hole you have drilled through the tube.
Smile it's contagious!
'74 R90S, '67 /2 Conv w/sc, '66 R50/2
'74 Harley FXE, '72 Harley FLH w/HD sc
'69 BSA 441 Victor Special, '74 R90/6 Basket case
'85 R80RT wreck for parts
Major Softie
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Re: Really stuck push rod tubes...

Post by Major Softie »

George Ryals wrote:Have you tried using a can of Freeze It? Liberally spray inside the tube on the head end of the cylinder. You could try a slide hammer hooked into the hole you have drilled through the tube.
Since the aluminum changes size more than the steel tube, I would think you'd have to be awfully fast using the Freeze It. With heat, you're using the differential expansion to your advantage.

OTOH, if you heat the whole thing and then spray the Freeze it inside the tube, it might just fall out. Course, you might create cracks in the head too...
MS - out
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dougie
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Re: Really stuck push rod tubes...

Post by dougie »

I would first try sticking the cylinders in a hot oven for an hour or more. Get them hot through and through.
I have had good results doing other jobs that way.
I've spent most of my money on women, motorcycles, and beer.
The rest of it I just wasted.
Deleted User 62

Re: Really stuck push rod tubes...

Post by Deleted User 62 »

dougie wrote:I would first try sticking the cylinders in a hot oven for an hour or more. Get them hot through and through.
I have had good results doing other jobs that way.
Yep, and do it when your wife isn't around... ;)
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George Ryals
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Re: Really stuck push rod tubes...

Post by George Ryals »

I'm bettin' that the interface between the steel tube and aluminum head will slow up heat loss of the head enough for the tube to shrink before the head looses enough heat to catch up. And I agree heating the head before freezing the tube would be more of a sure thing.
Smile it's contagious!
'74 R90S, '67 /2 Conv w/sc, '66 R50/2
'74 Harley FXE, '72 Harley FLH w/HD sc
'69 BSA 441 Victor Special, '74 R90/6 Basket case
'85 R80RT wreck for parts
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pkboxer
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Re: Really stuck push rod tubes...

Post by pkboxer »

OK, I've got 2 of the 4 out, then ran out of time.

Combination of my puller I made and some heat.

More heat than I thought would be needed and it seemed to help to put some on the tube itself, maybe so it went inside of the opening in the cylinder.

I did think of using the freeze spray to super chill the new tubes for installation (along with heating the cylinder) but now have a line on some free dry ice.

Thanks all
'74 - R90/6
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