I need some assistance, my sportster 07 was leaking from the rear head gasket and the rocker box on the front. I replaced the rear head gasket and rocker box seals, and the front rocker box seals. I use the service manual to torque down all the bolts. After I started it up, it is making a load knocking. I turned it off immediately. What did I do wrong? What is causing this knocking noise?

 

Hi Philip,
A few things to be checked:
Where does the knocking occur, can you locate it?
Did you bleed the tappets long enough?
Used the same thickness MSL gasket, or thinner?

 

Thank you for the reply TomCop. It sounds as if the loud knocking is coming from the rear rocker box/ or head. It is a loud metallic rapid knocking. Also the new rocker box gaskets were thinner, but not by much, it had the original orange coated harley gaskets, and the new ones are bare metal. And I am not sure if I bled the tappets long enough or not. What should be my steps to rectify this noise?

 

There are a few things you need to do. Open the rear rocker box and look for damage or markings. You will also have to check for damage on the valves- piston zone, maybe there was some unwanted contact between the two.
To assemble it again:
Make sure your piston is in top dead center ( both valves closed) when installing the rocker. Tighten the rocker bolts on, feel the pushrods and if you can't turn them , let it rest for 20 to 40 min. You will be able to turn them after this period. Repeat that until you reach the required torque specs of your rocker bolts.

 

No chance you put 883 head gaskets onto a 1200, right? That may sound like a stupid question, but I guarantee you, it happens.

 

Thanks TomCop, I'll break it down again this evening and try it again. Aswracing, I don't believe so, the parts came from the local HD. Last stupid question, I marker the push rods before I removed them, but I start to second guess myself. The rear cylinder, rear push rod is a tiny bit shorted than the rear cylinder, front push rod, correct? The color bands have worn off.

 

Yep indeed that's also something that you need to assemble in the right order. Have fun with it, and learn. From every little mishap you will pick up something.

 

No. The longer pushrods go on the exhausts.

 

So I took everything back apart, reassembled everything, I ensured the motor was top dead center, slowly bled the lifters, torqued everything to specs, ensured the push rods were properly placed, and I still have this terrible noise. I rev'd the motor slightly this time and I now have white smoke. What the hell is wrong. All help or guidance is welcome!!!

 

Hello Philip,
Take out the spark plugs and start the motor, feel where the noise is coming from. While you are at it, do a compression test. Check in the owners manual what the compression needs to be.
I need to ask, did you change anything else in the bike or opened anything else? (Tappers, cam)
Let me know what you have?