Top Dead Center (258) - JeepForum.com
Search  
Sign Up   Today's Posts
User: Pass: Remember?
Advertise Here
Jeep Home Jeep Forum Jeep Classifieds Jeep Registry JeepSpace Jeep Reviews Jeep Gallery Jeep Clubs Jeep Groups Jeep Videos Jeep Events Jeep Articles
Go Back JeepForum.com > General Technical Discussions > Engines & Drivetrain > Top Dead Center (258)

Introducing MONSTALINER™ UV Permanent DIY Roll On Bed LineHalloween Savings to die for!We have Engo 10k Synthetic IN STOCK!!! Hurry while supplie

Reply
Unread 07-17-2002, 09:08 AM   #1
Infedel
Registered User
 
Join Date: Apr 2002
Location: Washington
Posts: 87
Top Dead Center (258)

What's the best (and easiest) way to get your engine top dead center?

Infedel is offline   Reply With Quote Quick reply to this message
Unread 07-18-2002, 12:46 AM   #2
Quan
Registered User
 
Join Date: Mar 2002
Location: Bannedville (By Moronderator)
Posts: 1,098
excuse me? what did you just say?
__________________
[b]There comes a time... In every mans life, when decisions... have... to be made. Whether to toil, to labor, or just plain piss your days away.[/b]


[b][COLOR=green]Green[/color] Jeep Club Member #15[/b]
[b]My Jeep Made Me Broke Club Member #2[/b]

93 YJ I-6 w/ stuff

Keep the [COLOR=blue]greasy[/color] side down
[URL=http://members.cox.net/quanno/ford88.html]FORD 8.8 INFO HERE![/URL]
Quan is offline   Reply With Quote Quick reply to this message
Unread 07-18-2002, 05:48 PM   #3
lostboy
Registered User
 
Join Date: May 2001
Location: NY
Posts: 533
did you take it apart?...that makes it a bit more complicated ..otherwise it's a cinch...TDC...and this usually refers to the compression stroke (the cylinder will be firing on this stroke)....just line up the TDC mark on the harmonic balancerwith the 0 mark on the timing chain cover....pull the distributor cap off ..and the rotor will be very close to the place where the #1 spark plug wire comes out ..if it isn't..rotate the crank another 360 degrees til the mark lines up again and the rotor points at the #1 spark plug wire..this is TDC for the #1 cylinder...if ya took it apart before makin sure it was there to start with ...that's more complicated.....tell us what you need to do and we can help.....and spend 15.00 on a chilton's manual...better yet ...make freinds with a mechanic...just kiddin ..hang in there...ity isn't too complicated if you're willing to spend the time to learn
__________________
89 yj w/ mopar mpi and 4.0 head.94 ax-15 tranny and t-case, more mods comin.
lostboy is offline   Reply With Quote Quick reply to this message
Unread 07-22-2002, 10:42 AM   #4
Infedel
Registered User
 
Join Date: Apr 2002
Location: Washington
Posts: 87
Just rebuilt

Just finished putting in the motor. Somewhere in trbouleshooting an ignition issue (fixed with the Nutter Bypass), i think i got my distributor set wrong. When i fired up the engine the first time, the timing and everything was balls on. There was a knocking up front (i'm thinking the water pump), so i turned it off after a little while and quit for the day. Came back the next day to try and figure out how to eliminate the knocking, and when i started it up, it acted like the distributor was off and the cylinders were firing oddly. When i woudl go to turn it off, it would run on for a couple seconds after the switched 12V had been turned off already. This isn't suppose to happen. I'm a bit baffled and annoyed. I'm about to peel off the grill again and see if I can't get it TDC and reset the distributor. I was hoping for a more accurate way than "put your finger over the #1 spark plug hole and crank until you find maximum compression".
Infedel is offline   Reply With Quote Quick reply to this message
Unread 07-24-2002, 12:38 AM   #5
Hippo393
Member
 
Join Date: Apr 2002
Location: Kent, Ohio
Posts: 155
What's a "Nutter bypass"? Is that like a "Nutter-Butter" cookie?

I'm quite familiar with the 'ol "put yer finger over the #1 spark plug hole" routine! ha ha If you've done that, you don't need to do it again. Pull one of the plugs. Is it fouled? If not, are you getting spark? If so, then battery and coil are ok; rotate the distributor an inch at a time (it should be rotatable about 2 or 3") until it fires right. What is the condidtion of the points? Also check if the plug wires aren't just 180* off on the distributor (that's a longshot, I know). Keep the grill on and us informed.
Hippo393 is offline   Reply With Quote Quick reply to this message
Unread 07-24-2002, 11:08 AM   #6
Infedel
Registered User
 
Join Date: Apr 2002
Location: Washington
Posts: 87
The Nutter Bypass

John Nutter came up with what is now termed the Nutter Bypass. Rather than trying to explain and getting it wrong, here's the URL: Nutter Bypass
Infedel is offline   Reply With Quote Quick reply to this message
Unread 07-27-2002, 09:37 PM   #7
lostboy
Registered User
 
Join Date: May 2001
Location: NY
Posts: 533
I used a method found in the Jeep engine book. It involves removing the valve cover and using a dial guage. Basically, rotate the crank until #6 is at TDC;back off 90 degrees(counterclock),and set the dial guage to 0. rotate the crank clockwise until the guage reads .012 of lift. At this point,the timing mark should line up with the timing mark on the cover. This procedure is used on the exhaust valve rocker for #1 cylinder.
Just remember this gives you TDC for #6 so when you set your distributor back in, you'll either have to rotate the engine another 360 degrees until the marks line up again,or set your distributor back in on # 6..HTH
__________________
89 yj w/ mopar mpi and 4.0 head.94 ax-15 tranny and t-case, more mods comin.
lostboy is offline   Reply With Quote Quick reply to this message
Unread 08-02-2002, 11:54 AM   #8
Infedel
Registered User
 
Join Date: Apr 2002
Location: Washington
Posts: 87
Beating a Dead Horse

So i pulled apart my Jeep engine again last night. Getting to be quite a pro at it. I figured out what the knocking was. A screw that hold the first pully to the harmonic balancer was poking through the back side of the harmonic balancer and manged to chip away at part of the timing cover. Nuts!

I tried to use the wifes thumb to help me determine pressure in the #1 cylinder. I think she needs to go back in for calibration, it didn't work out too well.

While scratching my head and wondering why this isn't simpler, I made an observation. The Harmonic balancer has the tic mark that you pick up with the timing gun (strobe light). The timing gun fires with every firing of the #1 cylinder, which allows you to see this tick mark. I thought to myself, well how do you know you go the harmonic balancer on there correctly in the first place, in order to have the tick mark collaberatively lined up with the firing of the #1 cylinder. Well, the harmonic balancer is keyed into position on the crankshaft, so therefore, as long as the crankshaft is installed correctly, then the tick mark on the harmonic balancer will always have a direct relation to the orientation of the #1 piston.

What i can't remember though, is how many revolutions of the crankshaft there are, to the # of times the distributor rotates through 360 degrees. Is it 2 rotations of the crankshaft for every full rotation of the distributor? I think so. So really by using the any of the methods listed here, you still have a 50/50 chance of getting the #1 cylinder TDC the first shot.

Please provide criticsm, comments, etc...

Thanks!
Infedel is offline   Reply With Quote Quick reply to this message
Reply

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the JeepForum.com forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid e-mail address for yourself.
Note: All free e-mails have been banned due to mis-use. (Yahoo, Gmail, Hotmail, etc.)
Don't have a non-free e-mail address? Click here for a solution: Manual Account Creation
Email Address:

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.


Thread Tools


Suggested Threads





Jeep, Wrangler, Cherokee, Grand Cherokee, and other models are copyrighted and trademarked to Jeep/Chrysler Corporation. JeepForum.com is not in any way associated with Jeep or the Chrysler Corp.