Dwell Angle, Timing, and CHT sensor questions, Timing way off (well above 27 Deg) but runs...??? Options

[NJ914]

Looking for inputs from those who know...

Situation: Engine runs but timing is way off. 27 degrees is at 1800rpm[b]. 3500rpm is in the mid to upper 30's. When attempting to adjust the distributor to spec, engine dies. Only runs at higher timing angle. Not sure what the cause is.

1: Distributor gap is currently at 0.018" and dwell is 50-51 degrees through speed range.
Per the Haynes book, 1 degree of dwell can change the timing by 3 degrees.
Spec is 44 to 50 degrees.

Is this correct?

If I open the gap larger to bring the dwell down to 44 degrees, will this help bring the timing closer to spec?

2: Measured the CHT sensor cold and it was 3100 ohms. I believe it is supposed to be more in the 2000 - 2500 ohm range...?

What is the correct range for the CHT sensor cold?

It is supposed to drop below 100 ohms when up to temp. Is this correct?

Could the higher than spec resistance of the CHT sensor be contributing to the timing issue?

[Dave_Darling]

See if you can compare the marks on the fan to the marks on the flywheel.

--DD

[NJ914]

See if you can compare the marks on the fan to the marks on the flywheel.

--DD

Only one mark on the fan which is at 27 degrees...

[VaccaRabite]

See if you can compare the marks on the fan to the marks on the flywheel.

--DD

Only one mark on the fan which is at 27 degrees...

Put cylinder 1 at TDC. BE SURE IT'S AT TDC! Remember that a 4 stroke engine has two full revolutions of the flywheel for every 1 firing event. So you can think you are at TDC, but actually be 180* off.

Anyway, get to true TDC for CYL 1, and mark that with a paint pen through the inspection / timing hole in the doghouse.

You know you are at TDC for Cyl 1 when the piston is at the top of its stroke AND both valves are closed for that cylinder. Tht how you know and are SURE. Since you want to do the valves anyway, you will already have the covers off. I am not usually an advocate of going to TDC for valves, but this is a time when using the Krusty method isn't what you want to do.
This WILL NOT help you if your cam somehow got indexed incorrectly to the cam gear. That is the absolute worst case scenario though. Try everything else before tearing the engine down. It would be a huge bummer to pull the cam and realize that it was correct to begin with.

Zach