ET: Engine (Twin) Pushrod in love with cam follower!

[Bill Cannon]

I decided to play another game with the Egli to try to stem continuing leaks from pushrod tubes.

I already replaced the seals with O-rings 18 x 3 mm and black sealant but the leaks persisted.

I have found some slightly thicker O-rings at 3.53 mm and decided to fit them without removing heads.

So timing cover off and remove cams one by one to give as much access as possible. Rear cylinder done without problem but moving forward to the front cylinder I find that the inlet pushrod won't come out of the cam follower!

I remember when assembling the engine that I noticed this new pushrod was tight in the new follower so I used grinding paste until it rotated freely in the socket. But clearly I did not relieve enough metal as whatever I try I can't lift or rotate the pushrod from the follower.

Any ideas?

 

[davidd]

Bill,

I would guest that the timing cover has to come off anyway because the follower needs to be inspected, if not replaced. With the cam out you may be able to block the movement of the follower and pry up on the push rod. It sounds like you did the right thing during assembly. If there is a slight lack of support as a result of different shapes between the follower and push rod, the bulb on the push rod will collapse and become wider.

I pulled this one out of the racer when I had to adjust the clearance several times. I was racing and just plopped another push rod in and hoped for good luck. It is still in there years later.

I now check them dry and rub the push rod into the follower and check for shiny spots. I stone the shiny spots until I get no more shiny spots. Big Sid told me he uses a drill press and paste to mate them, althougth I have never tried that.

David

 

[greg brillus]

I've seen them sitting in the hole but not actually bottomed, then they eventually do bottom and it leaves a tiny steel ring suspended between the ball end and the main shank section of the pushrod. I make a point of checking the fit of all new push rods and cam followers now, making sure the ball is bottomed in the socket, that it spins freely, and that the push rod can move/pivot back and forth. This last bit is dictated by the reduced area behind the ball itself, and sometimes this needs modifying ...........All in a day's work when working on these engines.

 

[Bill Cannon]

Thanks guys, how do you pry the pushrod, I'm thinking I might have to make a slotted lever to get under the ball end. I've tried pliers of various shapes and grips without success.

 

[greg brillus]

Bill you might need to clamp on to the push rod just above where it goes into the follower socket with a good pair of small vise grips, and use a flat blade screw driver and lever/twist the screwdriver to pry the jaws of the vise grips including the push rod out of the socket. Any burrs on the pushrod can be linished out, and I simply grind a few thou off the OD of the ball end of the pushrod so it enters and spins freely in the follower socket. If you are suffering leaks from the tube seals, might I ask what kind of breather you are running, as leaks are common from an engine that struggles to breath properly. I have also found on some engines that the tubes do not align well with their bores in the crank case. In these instances I also use a smear of sealant before massaging the "O" ring into the housing, then wipe off the excess afterward. If you are unsure, just nip up the castellated gland nut into the head with no O ring at the bottom first to see if the tube pulls to one side or in the center. You might be surprised what you find. Good luck.............Greg.

 

[Bill Cannon]

Thanks Greg. This is a series D engine with new TP top end kit, so I am using the usual open pipe from front ex. valve cap over the engine and into a catch tank (read cycle water flask!). I should probably get rid of the banjo fitting as I know it can be restrictive. I'll put that on the list.
Bill

 

[brian gains]

all this talk of grinding and linishing, do the ss (?) push rod ends work harden or is that not an issue.

 

[Bill Cannon]

I think you are right Brian but it's only the tiny area in contact at either end.
Any way Greg's method was successful in removing the pushrod and I've used the Big Sid method in the drill and ground the end into the follower from various angles and cleaned up the pushrod with emery cloth and all seems well. Just about to put the cam back in and box up.
Job done, thanks again.
Bill