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-   -   How to 'rotate engine' ?? (https://www.cherokeeforum.com/f2/how-rotate-engine-122072/)

Roler Jan 28, 2012 03:37 PM

How to 'rotate engine' ??
 
Hi guys,
Could someone please explain how to "rotate engine with the engine starter motor for three revolutions"?
I thought rotate meant cranking, however this is mentioned in a FSM about sorting out starting issues and the battery is disconnected for this, so cant 'crank' it.

mdnov Jan 28, 2012 03:43 PM

Do you want to turn the motor over with the battery not hooked up? I just want to make sure that I am understanding you correctly.

Roler Jan 28, 2012 04:40 PM

Sorry, cant find the specific section in the FSM anymore.
It said to rotate the engine with engine starter with for three revolutions.
But you cant rotate it without the battery begin connected, now can I?

E.g. checking spark at the secondary ignition cable, it says 'roate the engine', which I understand means cranking the engine (with the starter motor/'engine starter')

So, is there another way (at all) you can rotate the engine?

mdnov Jan 28, 2012 05:26 PM

Ahhh, so you want to check the spark. The battery has to be hooked up to do that.

Roler Jan 29, 2012 07:25 AM

yeah, I understand, but can one rotate the engine without the battery hooked up?

And how do I so-called "rotate the engine for three revolutions" !?

DrShaggford Jan 29, 2012 09:09 AM

You can rotate it without the battery however that will not work for checking spark. It would be helpful if you let us know WHY you need to rotate the engine. You said "E.g. checking spark at the secondary ignition cable" is that why? If you do not need power for this you can simply throw a 3/4" wrench on the front of the main pulley and rotate it by hand.

Zack92MJ Jan 29, 2012 09:33 AM


Originally Posted by DrShaggford (Post 1496252)
You can rotate it without the battery however that will not work for checking spark. It would be helpful if you let us know WHY you need to rotate the engine. You said "E.g. checking spark at the secondary ignition cable" is that why? If you do not need power for this you can simply throw a 3/4" wrench on the front of the main pulley and rotate it by hand.

this.

caged Jan 29, 2012 01:06 PM

pull the coil wire. leave the battery hooked up. but you won't get spark.

tetrad Jan 29, 2012 03:26 PM


Originally Posted by DrShaggford (Post 1496252)
You can rotate it without the battery however that will not work for checking spark. It would be helpful if you let us know WHY you need to rotate the engine. You said "E.g. checking spark at the secondary ignition cable" is that why? If you do not need power for this you can simply throw a 3/4" wrench on the front of the main pulley and rotate it by hand.

I'm going to have to align TDC soon, and was wondering... which way does the engine naturally rotate (ie which way should I rotate it)? And will it only turn that way or will I clobber something by spinning it the other way?

Roler Jan 29, 2012 05:45 PM

Thanx guys, sorry I could not provided more info, but this is what I needed. Will also await answer to tetrad's question.

PatriotGT Jan 29, 2012 06:08 PM

A simple way to find out which way it rotates is to look at the fan blade,
following belt travel. It pulls air in. Same direction as you tighten the harmonic balancer bolt
(at least on mine)

DFlintstone Jan 29, 2012 06:21 PM

It turns counter-clockwise to for the driver. (that's anti-clockwise if your continent is up-side down). Most easily done with a 3/4 socket after pulling the E-fan. (just two little bolts). You will never get a spark like that thou!

sam24th Jan 29, 2012 06:23 PM

Not sure why your checking for spark when your trying to do it with the battery disconnected. You can pull the coil wire or CPS sensor and neither will allow the engine to spark. If you pulled the battery cable you can rotate the engine by hand by putting a wrench on the crank pulley and rotating it clockwise while standing in front of the block or counterclockwise if your inside of the vehicle.

Best way to check for spark without a timing light is to leave the battery connected. Pull the main coil wire and attach a sparkplug to it and ground it out. You should be able to see a spark while cranking if your ignition system is in correct operating order.

EDIT: I guess I posted at the same time as DFlintstone LOL.

Roler Jan 29, 2012 06:37 PM

thanx guys, but please stop ralking about getting spark, thats no longer the issue haha. But its good to see so many quick and adequate replies. ;)

DFlintstone Jan 29, 2012 06:41 PM

^post 13 "post edited"^


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