Join Date: Jul 2010
Location: Pittsburgh, PA
Feedback Score: 0 reviews
I am still struggling with the marks on the plate in relationship with the dampener. How many revolutions does the crank make per stroke? Or, When the marks are in alignment does that always indicate TDC. I guess it's the question of compression stroke or exhaust, right.
The camshaft turns at half the speed of the crankshaft, so there are two crankshaft revolutions per cycle. Although the #1 piston is at the top of its stroke every time the crankshaft marks are in alignment, the boundary between the compression and power strokes (TDC) only occurs every other crankshaft rotation. That's why you need the marks on the camshaft. If you've got a few extra minutes to read it, Wikipedia
provides a good explanation of the four-stroke cycle
'89 F250 2WD XLT Lariat Supercab,
7.3 IDI, C6, 10.25" 3:55, dump bed.
Mods: Gear Vendors overdrive, ATS 085/088
"Frankenturbo", boost and EGT gauges in pod,
K&N air filter, cold air intake, filter minder, rear
work lights, 'monback beeper, pintle+ball hitch,
brake controller, CB.
Wish list: 130 amp G3 alternator, front hitch,
new hood, fresh paint.