TDC Question

[Steeman01]

Hey everyone,

So I am confused as to where my indicator is showing TDC to be in reference to the markings on the crankshaft pulley.

According to the Rootes workshop manual I have, the largest and first marking is TDC (see photo attached). However, I got the car running fairly well but was surprised to see timing close to the 35° mark (using a timing light). I did not have enough swing in the distributor to get anywhere close to the 6°-10° BTDC recommended. So I pulled the valve cover and found TRUE TDC by hand cranking the camshaft (with a socket) and waited until the exhaust valve on the 1st cylinder opened and closed, then the intake valve on the 1st cylinder to open and close, then I used a feeler through the number one sparkplug opening to set the piston to TDC, within reason). This put the timing indicator pointing just shy of the 35° mark (see attached picture).... What the heck??

It idled great at the 30° and drove great and stayed at it around 85°C....

I'm at a loss...

I even check the points and their gapped appropriately at .015...

Thoughts? Advice? Help!!

SP

 

[AlsPine]

Hi, The outer iron ring of the damper has slipped due to the rubber part of the damper has gone bad and not gripping any more.
Wouldn't drive it until you replace it as it could come off and damage your radiator.
when you replace the damper, the timing marks should be back where they should be.
Sunbeam Specialties has them listed in his catalog, so give Rick a call to see if he has one available.

 

[AlsPine]

If you don't need the manual crank feature of the bolt that holds the damper on, Rick has a standard grade 8 bolt replacement.
You will need a deep socket to remove the damper bolt. If you are lucky, a breaker bar will get the bolt off, otherwise a air impact wrench will be needed.

 

[Steeman01]

Whew! Thank you @Alsp!! I thought I was losing my mind! I'll be calling SS tomorrow and ordering the part!

 

[AlsPine]

Hi, Did you get a damper?

 

[Hillman]

The best way to find TDC is with a piston stop. I made one from by:

• knocking the porcelain out of an old spark plug
• welding a nut to the top
• grinding the bottom of a bolt that fits the nut smooth
• screw the modified plug into the spark plug hole on cyl 1
  
• screw the bolt into the nut

Then turn the engine by hand until the piston hits the stop and can't turn any more. Mark the front pulley. Turn engine backwards until stop. Mark again. TDC is 1/2 way between the marks. To be more precise, screw the bolt in or out until the distance between the marks is minimal.

That said you likely have a bad damper but you may have wear in the keyway where the damper fits on the crank. When you get a new damper, double check its TDC with the piston stop.