Hi. Can anyone explain the procedures to find top dead center? Step by step if possible, more or less "finding top dead center for dummies" please

 

I imagine what you want is TDC for #1 piston for timing purposes?

Because each piston in an engine has a TDC, #1 piston is the one engine makers use for timing other devices on the engine

There is usually a mark/line on the crank shaft's pulley to denote #1 TDC and then a pointer on the front engine cover, when the pulley's mark/line and pointer are lined up then #1 piston is at the top of its cylinder, TDC.

BUT.......................with a 4-stroke engine each piston must pass thru TWO TDC's to complete one full cycle
The 4 strokes
1. intake stroke, piston is going down, intake valve open, sucking in air:fuel mix
BDC(bottom dead center)
2. compression stroke, intake valve is closed piston is going up, compressing air:fuel mix
TDC, spark plug fires to ignite air:fuel mix<<<<< this is the TDC used for timing
3. power stroke, air:fuel mix is ignited and explodes pushing piston down adding power to crank shaft
BDC
4. exhaust stroke, exhaust valve opens and piston is going up to push out the burnt air:fuel mix(exhaust)
TDC
1. again, intake stroke

So to find the correct # TDC you need to pull out #1 spark plug
Then rotate the crank until #1 is on Compression stroke(2.), you can use a compression gauge to see compression building up, so when mark/line on crank pulley comes around to the pointer you will be on TDC between compression stroke and power stoke, which is the "timing TDC"

Or pull out all the "other spark plugs" and leave #1 in place, rotate crank until you feel it slow, harder to turn, you are on compression stroke #1, can miss it, it gets hard to turn, this TDC mark is the one you want

Or if you are just timing a distributor or crank sensor then put pulley on TDC mark, install distributor or crank sensor and try to start engine, it is doesn't start then pull it out, rotate it 180 deg and reinstall, perfectly timed, lol.

 

Yes it's for timing. I am sorry I am somewhat mechanical. Brakes, ball joints, plugs, wires and oil changes but the whole camshaft synchronizer and ensuring that its right makes me doubt myself. I have read that you have to bump the engine is the a way to manually get it into top dead center? I have installed the new camshaft synchronizer and Cps. I took pictures and marked the tab location on the old one prior to removing it. Did the same with the new one but I doubt myself. If I messed this up the truck would have a rough idle all the time wouldn't it?

 

No, it would turn on CEL with a code that said CPS doesn't match Crank sensor or similar

Main timing sensor is on the crank shaft, and they ran engines for years with just that one sensor, Cam sensor was added for fine tuning and better emissions

Just unplug the CPS and see if it runs differently

 

Awesome thanks. I will do that tomorrow it's raining cats and dogs right now. I figured the cel would be on if something was screwed. Haven't had the truck that long. Just noticed the chirp one day and figured it out using a piece of wood like a stethoscope.

 

So I unplugged the cps. No cel,. Idle didn't change too much but with a little shot of gas it sputtered

 

Assuming 3.0l Vulcan engine, what Year?

 

2006 3.0l rwd

 

So I have been driving it. There is an occasional sputter when it idles. Almost undectable. But really nothing other than that no power loss. Idles at around 700rpm.

 

700 is OK for manual trans Ranger, a little low for automatic


Just FYI, the 3.0l Vulcan engine is designed as a high RPM engine

Most engines get best torque(power) at 2,400-2,800 RPMs
The Vulcan gets best power at 3,400-3,800 RPMs so 1,000 RPMs higher

So "drive it like a rented mule", lol, thats the way it was designed
Many complain about the 3.0ls lack of power, i.e. 3.SLOW, and they are not V8s, but many drive them like a regular engine so are shifting at 3,000rpms to next gear, yes NO POWER that way

At 3,500-4,500 you are NOT over REVing the engine

In 2006 the 3.0l Vulcan got best torque at 3,900 RPM, so even higher than older versions
Best Horse Power is at 5,000 RPMs

 

Do you think I should take out the camshaft synchronizer and reinstall it or leave it be? No check engine light at all.

 

Its fine if computer thinks its OK, computer has some lee way to adjust the "timing" so it doesn't have to be "bang on" like a distributor did, a few degrees one way or the other is closes enough.

If you notice the crank sensor is fixed, no adjustment, and its tone wheel is keyed to crank, so computer uses that as TDC for #1, then it looks at when Cam sensor shows TDC, and matches it up to cranks TDC, but it must be within a few degrees, or it will set a code.

The Cam sensor only rotates at 1/2 the speed of crank, so if crank is at 1,000rpms, Cam is only at 500rpms, this gives the cam sensor better "resolution" for when to open injectors for best performance and economy, which is also lower emissions.
If an injector opens just before its intake valve opens then some fuel will be wasted on the back of the hot valve(evaporates/carbonizes), if too late then not all the fuel gets in so lean burn and O2 sensor tells computer to add(waste) more fuel
If injector opens and intake valve open then air flow sucks most of the fuel in, so best performance and best economy, not as good as direct injection, because some fuel does stick to intake port and the back of the valve, but best that can be done with this type of system

 

Ok awesome. Thank you for all the info. Things seem really good so I figure I will leave well enough alone.