Pushrods getting beat up

[65 Eric]

Post by 65 Eric on Jun 7, 2007, 12:21am

Hey all, finally got my 65 running "ping free" and took it on vac. to Oregon, about a 1500mi. round trip. I'm running STD heads, a Andrews "B" cam with solids and one piece aluminum push rods. Bike ran great but after about 500 mi. it got real noisy. I stopped for the night and in the morning I found three of my lifters were very loose. The adjustment screw and lock-nut in the lifters were tight so I pulled the push-rods out and saw that the aluminum tube under the hardened tip was being peened down. The tips were actually rolling down the edge of the aluminum tube and making my push-rods shorter. I re-adjusted them, got to Oregon and ordered another set which was over-nighted to me. I wanted steel push-rods but all I could get were the same Colony aluminum push-rods that I took out. Of course the same thing happened. Has anyone else had this problem and are steel push-rods the answer? btw, made it home ok just had to adjust my push-rods a few times. I've also ordered some chrome-moly tubing and plan on pressing the tips from the aluminum push-rods into them.

appreciate all help,
Eric

[bibs]

Eric.....just my .02 here but I'd lose them pushrods and go with rivera taper lites......they are steel and bullet proof!!!!!I'd venture to say that your pushrod woes will be over with!!!

[65 Eric]

Thanks Bibs!
The aluminum ones are history, I couldn't find steel push-rods in any of my catalogs but I'll look up Rivera on the old 'puter here and see what I can find.

Eric

[bibs]

Eric...shoot me a P.M......I have a dealership with midwest and V-twin....can get 'em for ya cheaper than you can if yud like!!

[wreck74]

The Andrews B cam has a lift of 0.507 thats a lot. you may need to do some spring work to make it work.

[Cotten]

Eric!

Doesn't S&S make steel pushrods anymore?
Although I have encountered aluminum rods that have crushed, most survive for decades. I even used to run a set with aluminum ball ends!
If adjusted loosely, however, the hammering of the valvetrain will fatigue aluminum much more quickly than steel, of course.
Please consider the pounding that has been transferred to the tappet rollers as well.

...Cotten

[Skip]

Mr. Cotten...your opinion please.....in reference to solid push rod adjustment...instead of getting the lifter to the bottom of it's cycle to adjust...have you ever heard of adjusting at Top Dead Center????....someone advised me to do so, and I had never heard of it being done that way until here recently...your thoughts and the draw backs if any......Thanks Skip

[Cotten]

Kinda hard to work them adjusters under valvespring pressure.

....Cotten

[65 Eric]

Gentlemen, thx for your replies,
Wreck74, I'm running STD heads which are set up for a cam with up to a .550 lift so I don't think that's the problem. I didn't actually check them but I called STD and spoke to their "motor builder" and he was familiar with this problem and especially with Colony push-rods. Like Mr. Cotten he also suggested S&S steel push-rods.
Mr. Cotten, I'll be buying a set from S&S. I was going to fab my own but after taking apart the Colony ones to get the tips out I measured the end that presses into the tube and found .0015 difference in the diameters and the finish was so bad it almost looked like threads! No wonder I could grab the tips on two of them and move them up and down in the push-rod and this was the new set before installation. I'll pull my tappets (new) and inspect them while I'm at it.
thx again everyone,
Eric

[PanPal]

I think they meant with the pistons at top dead center. Both valves are closed.

[Skip]

Yes Panpal that is what I meant to say....does that work...it would seem simpler....Skip

[fourthgear]

As far as the TDC adj.of push rods , It would depend on the Cam in there , you could have one still a little on the lobe ramp. The method of the valve opening opposite ( intake or exh.on the same cyl. )of the one you are adj. eliminates that possibility.

65eric
Did it look some thing like this,

normal_DSCN01370177.JPG

[65 Eric]

Fourthgear, damn! no, mine actually had the tips still on them but where the tip meets the aluminum the aluminum was rolled down so evenly it almost looked intentional. The tips being loose caused a constant "peening" of the tube and was perfectly round and even all the way around. I hope some steel ones and a little tighter adjustment is the answer.
Hey Mr. Cotten, are these the aluminum tips you were referring to?

thx,
Eric

[Skip]

Hey Eric...just ordered a set of the steel push rods from S&S....at $65 a set, they had ought be better...I will try anything that may make it better...going to adjust them tight....been running my Colony specials REAL loose so far this year...about 700 miles so far...and only problem I ran into was the damn noise....starting had never been easier...tried to adjust them to the spin no shake rule, and could not even get a back fire....go figure...that is when the local guru told me to adjust them at top dead center...tried it...compression is off the gage...have to retard the timer now and never had to before...starting first kick hot or cold...I am stumped my self...Mr. Cotten says tight, (and as a rule I try to follow his advice and suggestions)...manual states a lot tighter than I have them...I worry about the looseness of them...runs strong though...curiouser and curiouser...good luck to you...sometimes it seems like a crap shoot to me.....Skip

[Cotten]

First,
You shouldn't adjust valves basis piston position because the cam can be timed independently.

Next,
Notice in Fourthgear's photo that the pushrods were rubbing within the covers. That's unfortunately typical of fat aluminum rods. The crushing of the tubing must be considered a catastropic failure in the making.

Back to adjusting,
Aluminum rods have a different thermal coefficient than the cast iron cylinders. That's why the rods need to be adjusted unusually tight, as they can literally fall out when the cylinder has lengthened before hot oil can lengthen the rods.
The period of 'slap' is when damage is done.
Steel rods are more similar to the cast iron, so they can be adjusted easily to a clearance that will remain more constant through the heat cycles of a motor.
Again I must stress that the pounding of loose pushrods contributes to premature roller failure,...and believe me, that's catastrophic!

....Cotten