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Discussion Starter · #1 ·
Having a problem with installing the rocker arms on a 98 4.0 with 235k.

To make a long story short, I drove the Jeep from California to Las Vegas, the Jeep drove around town fine for a few weeks, had been using/losing some coolant, but when I tried to drive from Las Vegas to Florida I only made it to Arizona. A shop there did a compression test and coolant test and said I had a blown head gasket. I had it towed back to a friends house in Vegas to work on it.

I pulled the head and found the #1 and #6 pistons to be a lot cleaner than the other four, I figured from the coolant leaking in there. I got up all the parts I needed to put it back together, and have the head on.

I kept all my pushrods, rocker arms and stuff in order.

I'm trying to put the rocker arms back on now and they aren't all lining up with the top of the valve correctly.

I think I need to bring each cyl to TDC before tightening the rocker arms down?

Whats the best way to know the piston is at TDC(screwdriver in spark plug hole?), which way should I rotate the engine, clockwise or counter-clockwise?

Any help very much appreciated.
 

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The crank makes two full revolutions for each cam shaft revolution so you have to know which TDC rotation crank is on to get cam lobe in proper position
TDC compression stroke vs TDC exhaust stroke for both TDC piston one at top but one only TDC compression has both valves closed

A friend had a 302 boss 69 stang with solid lifters
I did the cold adjust then went to lunch told him to do same proses after running for hot adjust and he screwed it up completely as he did it 360 degrees out on crank


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That's odd. Did you remove the lifters too? If they're seated properly, everything went back into the same spot, meaning you didn't switch the position of anything or turn a push-rod upside down everything should go together fine. Make certain the lifters are properly seated against the cam and didn't move upward, sometimes they can be tight in their bore for one reason or another and not sit against the cam lobe. Also make sure the push-rods are properly seated in the lifters. Good luck.
 

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By the picture it looks like Intake valve is wanting to open. Like Digger84 said you need to be on Top Dead Center of the compression stroke for the cylinder you are working on so that the both intake and exhaust lifters are on the bottom of the cam lobe. There are several "old school" ways to make sure you are at TDC compression. I would start with cylinder #1 and roll the crank until the #1 piston is up and both intake and exhaust lifters are on the bottom of the lobe. You can make sure they are on the bottom of the lobe by looking at the pushrods (rockers removed) they should be level with each other. Once you establish TDC on compression stroke for cylinder #1 then tighten the rockers for cylinder #1.
Now you just rotate the crank 120 degrees clockwise and you will be set up on cylinder #5 (next in the firing order), then rotate for cylinder #3 and so on for the rest of the firing order (1,5,3,6,2,4). You can always confirm that the cylinder you are working on is a TDC on compression by making sure the pushrods for that cylinder are level with each other.


NOTE: All of the above is assuming that you do not have a lifter sticking and the pushrods are seated in the lifter correctly (not on the side) like demarpaint suggested.
 
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