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[TJohnson]

I'm a new TDR member and just purchased my inlaws 93 TD. The truck has 135K and gets 22 MPG in the city and 24 on the Hwy. I was told that the valves had never been adjusted on the truck since it was purchased new.



I tried to locate TDC using the instructions found on several good web sites but could not get the pin to go in the hole. I also tried turning the engine over using the altenator bolt but it only slipped. I eventually put a socket on the lower pulley and good gracious what a job! It took all I had to turn that big boy over!



I'm in the Air Force and payed a visit to our motor pool mechanics and their advice was to not mess with it. They stated that they never have any problems with Cummins. I just want to do what's right because I plan on passing this truck down to my son.



I figured I'd give the forum a try to get the experts opinion.



93 2WD extended cab, K&N air filter, straight exhaust.

 

[drturf0]

did you try to turn the motor backwards with the alt. pulley ? that normally works but only if you are turning the motor backwards.

 

[DavidGardner]

Use a 22 milimeter socket eith a rachet on the alternator pully. Stand on the passenger side of the engine and pull the rachet handle toward yourself slowly. This should work. If you try to turn it the other way it will just slip the belt. Done mine several times and this always works. I have never been able to engage the pin they talk about. Cant even find it!

Good luck.

 

[TJohnson]

So if I'm looking at the front of the engine, is backwards counterclockwise?

 

[drturf0]

yes counterclockwise , thanks dave that was a better disc. them i gave him , my mind just went bl___________ank.

 

[TJohnson]

How do you know if you're TDC if the pin is not engaged? Are you saying to look at the gap in the valves?

 

[DavidGardner]

Yep-Standing in front of the trk looking tward the cab, turn it counter clockwise.

 

[Matt S]

Welcome to the site. For the first time it may take 2 people, one to turn the engine over and the other to push on the pin. It is a good idea to mark the crank pulley when you find it. You can also look at the vavles for the tension to be released and adjust them that way. I found that was easier than the book as I didn't seem to match what the book said when they were supposed to be loose.

 

[NuttyMopar]

Finding TDC

I agree with the 'taking 2 persons first time' theory. It is hard enough to get your hand down around that pump to even FIND the plunger, then to also reach around and turn the motor over. I just can't see how any ONE person can do that. I also agree with the MARK your crank once you find TDC. It makes life so much easier after that is done. Since I have done that, I just crawl under the truck and turn motor over using the bottom pulley and wait until I see my marks. It did take me several times to find TDC using the plunger but once I found it, (and I couldn't believe I did), I marked the crank.

 

[CRWilliams]

I bought the barring tool from Snap-On, $40 well spent. I can lay under the truck and turn the engine over and use a pry bar on the pin at the same time, it takes some practice but is fairly easy. Snap-on also makes a tool that clamps on the alt. pulley and sandwiches the belt allowing you to turn the engine over, I need to find out what the price is but it might be worth it.

 

[Scot]

Oddly enough, one of the wrenches I built out of 3/16 plate to change the waterpump on the wifes Explorer also fits the nut on the fan of the CTD. The wrench being about 24" long makes turning it relatively painless. I took a piece of 2x1/4" flatbar about 14" long and pushed the pin by wedging against the KSB valve.



On mine, the pin engages about 1" to the right of one of the big notches on the harmonic balancer. THEN MARK IT