Jump to content

Recommended Posts

Posted

I am trying to confirm accuracy of the TDC pully mark with pointer. I removed the head plug above the #6 cyl and expected to be able to insert a long piece of wire through the hole to confirm piston position for TDC. Beyond the threaded hole is solid metal (carboned up). What am I missing here?

Thanks in advance

Don

Posted

..using the metal rod will get you close enough if you are wishing to establish the timing mark on the lower pulley compared to the TDC of the timing tab..if you are just a degree or so off..would not let this concern you..you have already confirmed the presence of carbon within the cylinder..time it as per the specs and the original mark/position..

Posted

To be accurate, you can put a wire or screwdriver down the hole and use it as a stop. Turn backwards until the piston touches, mark the pulley, turn forward until it touches again, mark the pulley. TDC is exactly half way between the marks.

If you use a wire be sure to bend a T handle on the end. You do not want it to fall down the hole or you will have to take the head off. Guess how I figured this out lol.

Posted (edited)

No I dropped a wire down the plug hole of a Triumph motorcycle doing the same trick. After I took the head off I made a special tool of brazing rod, bent into an L with the measurements marked in red paint. That one fell into the engine too. So I made one in a T shape too big to go down the hole.

Triumph motorcycles have no timing mark as such, you time them with the piston 7/16" below top dead center. So you have to find TDC, mark your measuring stick, measure down 7/16, turn the engine 1 full turn then stop it at 7/16. Turning the engine by putting it in gear and turning the back wheel. So it is easy to drop something down the plug hole if you are not careful. You can't use a screwdriver because it hits the gas tank.

Edited by Rusty O'Toole
Posted

never messed with a Triumph motorcycle and tuning..but I did own a Norton 850 Commando..I accidently went past the mark, (plate moved fast) and killed the engine..I retarded it but found out quickly not enough it seems, I kicked it, it kicked back and I was on my butt for a good 15 minutes and limped for over a week..found out later that my wife's family though me wierd that I had 5 licensed and registered motorcycles, GLH, 41 Dodge truck along with the daily driver...(we had just met)

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.

Terms of Use