Thanks. Someone mentioned to be about being careful with messing up the timing. I don't 100% follow how that occur. If I'm finding tdc, relieving all pressure on the rods and torquing everything back up to spec, how does timing play into this ? Is there any special start up procedure?

 

No way to mess up timing unless you get into the cam plate and remove the cam gears....

They probably meant making sure the pushrods are on the base circle (cylinder at TDC) when you torque down the rocker arms.... and wait for the lifters to bleed down before rotating the engine.... open pushrod tubes and make sure you can spin the pushrods with your fingers. That's how you'll know they have bled down, then rotate the other cylinder to TDC to torque that one... again, wait for lifters to bleed down before rotating the engine after that cylinder is done....

It's not that hard... just follow the manual and take your time


PS- here's an old pic I took when I did the rocker plate drill mod..

 

Awesome , thanks for the pics. So really the 2 ways to ensure no pressure/tdc are spinning the pushrods and also the rocker arms should have a little play too correct ?

 

Looking at this picture, it appears that the lower rocker box gasket is being shown upside down. I'm assuming that the picture was taken to demonstrate what the wrong way looks like--leaving the tunnel next to the index finger unsealed by the gasket, and blocking the breather operation like in the statement.

The gasket ridges that seal that tunnel are visible in the picture, and when flipped over right-to-left, cover that tunnel in the head perfectly. It's a little confusing because the bolt holes line up either way.

All the best,
Shane

 

Unless I misunderstand your question, there are two separate concepts here... forgive me if you already understand this....

1) finding TDC to keep the least amount of stress on the pushrods/rockers (valves closed) when assembling or disassembling the rocker arms.... 2) After torquing the rockers, waiting for the lifters to bleed down before turning over the engine..

The problem you are trying to avoid is this; If the rockers are torqued down and the lifters haven't bled down, the valves are under tension, and could be partially open, even with the cylinder at TDC, and the cam on the base circle.... If you were to rotate the engine at that time, a valve could be hit by the piston = damage... Once the lifters bled down, with the cylinder still at TDC, the cam still on the base circle, there is no tension on the valves and they are fully closed... there is then no risk when rotating the engine.... This could be what someone meant, when they cautioned you about "messing up the timing"

Many things will decide how long it takes for the lifters to bleed down. I have had them bleed down in like 5 min. and I've waited 35 minutes one time. Once, I did one cylinder in the evening, then did the other the next morning... not because it took that long for the lifters to bleed down, I was just tired and wanted to go to bed...

Good luck and enjoy yourself, it's actually kind of fun working on Harleys.... once the mystique is gone..

 

You are correct. I took the photo both ways and am still learning how to put in arrows to make salient points like this or the oil return holes I normally drill out.

 

Thanks for that info. 2 questions . Are you saying the lifters need to bleed down once the project is complete and I want to start the motor? Not sure if I fully understood.

Second question. I can only get tdc one at a time correct? So when I finish one rocker box and start the rear one I would need to rotate the engine to tdc for the 2nd cylinder ?

 

Found my answer on having to find tdc on each cylinder.

Still didn't understand about bleeding down the lifters. Aren't they already bled down before I remove the rocker assembly ? Thanks

 

He’s talking about on assembly. Say you start with the front cylinder, it’s on the base circle, when you install the pushrods and torque the rocker. You need to wait for the lifters to bleed down before rotating it and putting the rear cylinder on the base circle.

 

Gotcha , understand now. How do you know when it's safe to rotate ?

Don't the lifters bleed down when you initially find base? Or do they go back up when your working on everything