So i took out my distributor to replace it and some genius decided it would be a good idea to crank the motor while it was out.....FML.... So does anyone know how to find TDC without pulling the head off?
I need to find top dead center
afdude
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easy stick your thumb over the number one cylinder spark plug hole and bump the engine. When you feel air pushing your finger off you know thats the compression stroke. When you are on the compression stroke on the number 1 cylinder line up the marks on the harmonic balancer. If you can not read them you can stick something like a metel coat hanger down the spark plug hole and feel when the piston is at tdc. just make sure its the compression stroke. This is probably the redneck way but its always worked for me.
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This is how you find TDC. Just remember if you pass the 0 mark you can't turn it backwards...you have to go all the way around and find the compression stroke again.
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Why can't you turn it backward? Every engine I have ever worked on could be turned backward? And for Distributor purposes, the timing mark at zero is not rotation critical, that is, it doesn't matter what direction you turn things to get to TDC, once there you install the distributor.Ive always heard your not supposed to turn it backwards because it can cause the chain or belt to loose tension skip a tooth. So Ive always turned it all the way through if I passed tdc. But I guess if you have done it several times with no problems it must be safe to do. Ill keep that in mind next time cause its a pain when you go a hair past and have to rotate back through.
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That's on overhead cam engines with belts. It is more accurate to get to TDC when rotating the engine in it's normal direction as the timing chain will be tensioned as it would be when running.
It ain't that hard to get to TDC without going past anyway.
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Because if you turn it backwards you take the tenson off the chain. So while the mark might line up with the 0 the cam will be off. The amount you are off depends on the amount of slack the chain has.
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My point exactly. And since the distributor is driven off the cam, your distributor indexing would not be accurate.
OK so I did the finger over while turning it by hand and felt for the compression stroke and when i felt pressure i stuck a solid piece of wire down the hole and waited till it stopped coming up.. hope this works Ill post again when autozone gets my distributor in.
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AND you watched for the TDC mark on the balancer to line up with the pointer? FWIW, take a look at your balancer to see and see where the mark is. These 4,0 balancers are known to delaminate and the outer ring moves. You'll be able to see the deteriorated rubber if it has.
thought that you could locate the #1 spark plug wire on the distributer. then draw a line to the bottom of the distributer base. then remove the distributer cap and turn the engine until the rotary button is pointing to the line that you drew.
i thought that this would get it close.
then again maybe i think i may be listening to the wrong voices hahaha
i thought that this would get it close.
then again maybe i think i may be listening to the wrong voices hahaha
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If you guys are driving around with a vehicle who's timing chain is so worn that the cam is a full gear tooth off by rotating the engine backwards you should think about replacing your timing chain. The whole point is to get the distributor in place so you can then adjust it once the engine is running. I have never had a problem getting the distribtor to drop in and then run fine by turning the engine "backwards" to top dead center.
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You can't adjust the postion of the distributor on the 4.0, unless you grind the indexing tab off.
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Correct. That's why it's important to do this correctly. The distributor indexing has little to do with ignition timing. That is done by the ECU. The distributor has a stator inside it which controls the sequential injection firing.
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Yes the cam sensor in the distributor controls when to deliver the fuel :thumbsup: On the 2000+ there is no distributor but there is a cam sensor that does not have an indexing tab...that was fun getting it setup correctly
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It seems the ECU only has a limited range in which it can control the timing. That's why those of us with coil rails have to reindex the camshaft position sensor.
Removing the coil rail should be the hardest part. Indexing the CPS is easy. Remove the sensor, loosen the fork that holds the collar, and line up two holes with a toothpick or drill bit.Yes the cam sensor in the distributor controls when to deliver the fuel :thumbsup: On the 2000+ there is no distributor but there is a cam sensor that does not have an indexing tab...that was fun getting it setup correctly
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Sorry, I was trying to point out that if your chain has so much slack by bringing the crank back a little to TDC that you can actually get the distributor a whole tooth off, you should fix the timing chain before you do anything else. Then again, If people should do whatever they are comfortable with. :thumbsup:
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