Hello All,

Real bonehead question. In the proccess of rebuilding my 99 vulcan. Pistons, crank, cam, lifters, cyl heads, timing gears and chain, timing cover and oil pan are installed.

Going for the new synchro at this point.

Crank and cam are still in the 'just installed' position. They have not been rolled, the keyways and marks are still lined up.

0 (tdc) is right on the mark to the right of the crank position sensor.

Is this my TDC on compression or intake stroke? Is this the position that I want to install the synchro??

Yes, I could postpone synchro install until intake, rods and rockers go in, to roll it over to check the for suck or blow at the plug hole, but I am famous, or infamous, for setting distributers 180 out, so I wanted to try to head this off at the pass.

Thanks for any input.

 

It should be. The best way to tell is to put a bit of tissue paper into the no. 1 spark plug opening and turn the crank clockwise. As soon as the piston starts coming towards the top on the compression stroke it will blow the tissue out of the hole. continue turning the engine to TDC and then you're ready to install the cam position sensor. Do you have the tool to hold the sensor in position as you insert it?

 

OK. I do understand that.

I guess what I meant to ask was when the timing set is freshly installed, and the timing marks are all lined up, what stroke would the crank be in? I'm trying to figure out, in the factory, when they put these together, the timing marks are aligned. When they drop in the synchro, does it go with the timing set marks still aligned, or do they roll the crank once.

 

Turn the crank until #1 intake valve closes. The continue until the TDC mark lines up.

 

Cylinder #1 should be at the top of the compression stroke (both valves closed).

Check out this thread with photos of where the camshaft position sensor synchro should be:

https://www.ranger-forums.com/engine-drivetrain-122/how-replace-camshaft-position-sensor-synchro-1999-3-0v-114186/

 

OK I get where TDC is on the damper with those pics.

I am curious about the marks on the timing set. When the crank mark and keyway are up and the cam mark is down, is that tdc on compression, or is it tdc AND 360 out?

 

To try to simplify what I am asking, which drawing represents TDC on the compression stroke?

 

Example one would be TDC on the compression stroke but its still best to double check with the tissue or with your thumb over the spark plug hole

 

Thanks Guys,

I just did it the way in the books. FYI: It turns out that ( with this motor anyway ) example one did in fact sit on the top of the compression stroke.

Thanks again.