hi n dry

Hey all! I recently set about changing the distributor cap on my 1990 XJ and the cap holddown screw broke off in the housing. Great! So I decided to pull the distributor out of the block and take it to the bench to drill out the broken screw. I first rotated the crank to bring the timing mark up to the timing tab while watching the the rotor coming around to the no. one cylinder position. I removed the hold down bolt and pulled the distributor out. I had also pulled the plugs to change them so I shown a flashlight into the cylinders to just have a look and noticed the no. one piston was down instead of at TDC where I thought it would be. After fixing the broken screw I went to put the distributor back in and apparently the crank pulley is 180 out! Is that possible? What do I do to get it right? Did I screw up the distributor removal procedure? Somebody please help! I do most of my own car repairs so I do know a few things, but I might of screwed this up somehow. I don't want to try and start it till I understand what went wrong, Thanks!

Ant.

Just rotate the crank 180 degree and line up marks ,
Then replace the dist with rotor facing position No. 1...

I have a 99, cherokee and my No. 1 is at the 5 O'clock position..

I would start with the rotor facing the 4 o'clock position and as it slides in the rotor will turn to the 5 O'clock position once completly seated...

Ant...

freegdr

It ran b4 you pulled it out dont turn any thing . Put dist back in exactly as you pulled out.....

hi n dry

Well I've been considering your guidance but just not understanding what is happening. I bring the no. one piston up and feel for compression so I know I'm on the right stroke but the piston is about half way down the cylinder for the power stroke before the timing mark arrives at TDC. Re-installing the distributor is easy enough but things just aren't in sync.

DFlintstone

The crank pulley is two piece with a ring of rubber separating the outer ring. They can, and do fail. Maybe that's what's going on. Sometimes you can see the rubber sticking out.

Don't forget most of the books and diagrams are wrong, #1 is at 5:00 as viewed from the side.

Ant.

It is very simple to do, Just take your time.. I know it can seem over welming at times.. I used to think this was so hard to do but like I said it is very simple...

Here is an image to help you..




First you will need to get the timing on the motor on TDC, Pull the # 1 spark plug, stick your figer over the hole where the plug goes. Have someone rotate the crank till you feel pressure on your finger, Then stop. ( now rotate crank clockwise till timing marks line up ). Now take the dist. in your hand with the rotor on it.. Position the rotor at 4 O'clock position.. Now start to slide the distributor in place, as it slides down the rotor will rotate to the 5 O'clock position... If rotor goes passed the 5 O'clock position when fully seated, then repeat process but start at 3 O'Clock instaed of 4 O'Clock..

Good Luck,

Ant...

DFlintstone

That is not correct. There will be pressure nearly as soon as the piston starts up on the compression stroke. Top Dead Center, (TDC), can be tough to nail without the timing mark. There at least three ways to get pretty close, but if the harmonic balancer, (crank pulley), is shot, better to start there.

If the mark is not up/on, on, with # one or six up, the pulley should be changed. Since actual straw is pretty rare, a guy can use a drinking straw to get pretty close, feeling, watching the piston, ('s) come up.

Otherwise, a nice post, (as usual), Ant!

DFlintstone

Ant, if it read "rotate the crank till you feel pressure on your finger, Then continue clockwise until the mark lines up with TDC" (That's if the outer ring/mark on the pulley has not moved), you would have nailed it! (with a nice diagram Btw)

Ant.

Well thats I was trying to say, I think I did have to go a little further when I put my motor back together.. Hope he gets it...

Man I remember when I first started working on my own car(s), I thought it was realy hard to find TDC, I remember being realy intimidated with doing that step..I would never do it.. I always had someone else do it for me.. LOL..
And the part that I realy didnt like was swapping timing chains, I was always scared I was gonna screw something up, But it is rather simple now..


Ant...

DFlintstone

Gotchya", Yep. Dad more or less threw me in the water and would come if I didn't come back up! There is such a thing as "valve crossover" . That's where the opposite cylinder (#6 here), is coming up on exhaust. You can lay a straightedge on the rockers, (for #6), and get it even with the head. As #1 comes to TDC on compression, #6 is just finishing exhaust and opening the intake valve. When those are perfectly even, the mark should be near TDC. That would be "crossover" for #6. Booger is, the valve timing might not be exact to a degree. (you can also check a slipped timing chain that way if your pulley mark is reliable)

Besides the "straw method" you can attach a fitting and tube to the plug hole and fill the works with oil. TDC will be very close to where the oil is highest in the tube.