F1loco Posted November 9, 2019 Report Share Posted November 9, 2019 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? Quote Link to post Share on other sites
F1loco Posted November 9, 2019 Author Report Share Posted November 9, 2019 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? Quote Link to post Share on other sites
F1loco Posted November 9, 2019 Author Report Share Posted November 9, 2019 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 Quote Link to post Share on other sites
Motorsport Mickey Posted November 9, 2019 Report Share Posted November 9, 2019 Don, You have a PM, check out the envelope on top of the page, have a read. Mick Richards Quote Link to post Share on other sites
BlueTR3A-5EKT Posted November 9, 2019 Report Share Posted November 9, 2019 Would this help? https://www.macysgarage.com/cam degree.htm Peter W Quote Link to post Share on other sites
dingle Posted November 21, 2019 Report Share Posted November 21, 2019 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 Quote Link to post Share on other sites
RogerH Posted November 21, 2019 Report Share Posted November 21, 2019 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 Quote Link to post Share on other sites
dingle Posted November 21, 2019 Report Share Posted November 21, 2019 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 Quote Link to post Share on other sites
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