Jump to content
F1loco

More timing/TDC issues ...

Recommended Posts

Went to finish this project this morning, but for some odd ball reason I am getting both valves #1 fully closed, rotor on #1, but the piston is actually 180 (BDC)?  If I take it to 180 (BDC) on the degree wheel,  the rotor is actually pointing #3.  The #1 intake valve appears to be fully opened on the cam at the 110 mark per my dial.  So why in the world is the piston at BDC on the wheel when in fact it is TDC, yet my rotor and valves say something different?  If I take it to 180 BDC, which in reality is TDC for the piston, not only is the rotor pointing at #3 on the cap, but the #1 EV begins to open around 140, so at 180 on the wheel the EV is opening and not fully closed.

Suggestions?  

Share this post


Link to post
Share on other sites

Started from scratch again.  I think my cam gear was about 180 out. I now get the rotor on #1 on the non-compression stroke at TDC and the rotor at 4 on the compression stroke (assuming this is the TDC  compression as the intake valve begins to open just before TDC on that revolution, which would suggest the dizzy is 180 out?  Can I change the key w/o dropping the pan?

Share this post


Link to post
Share on other sites

So I convinced myself the dizzy was also 180 out.  Took it out, punched out the pin, and rotated the gear.  It appears to be firing on TDC #1 with rotor at #1, and full lobe on IV#1 open at 110.  Now to button it up and hope I didn't screw the timing too off to get it firing. Of course, that cross brace is up on deck next .... sigh ...

 

-Don

 

 

Share this post


Link to post
Share on other sites

Don,

You have a PM, check out the envelope on top of the page, have a read.

Mick Richards

Share this post


Link to post
Share on other sites

Any chance that the pulley was installed 180 deg. off?  Remembering back when I had a TR3/4, the pulley (and TDC mark) is installed with the crankshaft key pointing down instead of pointing up, as on most cars. This results in the TDC hole on the pulley actually being at BDC.

Berry

Share this post


Link to post
Share on other sites

The TR4/4A crank pulley is a spilt affair and can easily be fitted 180 degrees out. 

I have some form in this department. :)

 

Roger

Share this post


Link to post
Share on other sites
2 hours ago, RogerH said:

The TR4/4A crank pulley is a spilt affair and can easily be fitted 180 degrees out. 

I have some form in this department. :)

Yes Roger, that was my experience, I fit the pulley with the key up and couldn't understand why the pistons weren't at TDC. 

Berry

Roger

 

Share this post


Link to post
Share on other sites

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.   Restore formatting

  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.

Loading...

×
×
  • Create New...

Important Information

Please familiarise yourself with our Terms and Conditions. By using this site, you agree to the following: Terms of Use.