george7941

The engine will not start now. It will crank for a second or two and then the engine starts to bind.The engine turns backwards freely using the alternator pulley. The engine seems to bind only when turning in its normal direction (clockwise, looking from the front of the engine). After this binding I can hear a scraping noise from the rear crankshaft area when I turn the engine backwards. The scraping noise will last for about a sixteenth of a turn of the crankshaft and then the noise goes away and the engine frees up. Tomorrow I will try my barring tool and turn the engine forward manually.

I will also take off the crank sensor and look for signs of a loose tone ring. Hopefully it is not anything more serious than a loose tone ring.

306k km/192k mi on the well maintained engine. It does not burn oil.

Clunk

I recently read of a piece of pressure plate or loose bolt in the bell housing.
It was reported noisy.
Anyone else catch that?

george7941

I have an inspection plate at the bottom of the bell housing and I took it off and everything looks normal in the clutch area. I had someone turn the engine over while I looked and the noise is not from inside the bell housing. Close by but not inside.

SIXSLUG

Can you pull any codes out of it?

patdaly

Can you try levering the flywheel gently towards the rear? Then have someone push in the clutch to see if it is moving front to back.

Could be something weird like a failed thrust bearing or worse, broken crank.

Hope it is only the tone ring, but my luck never runs that way.

george7941

Took another look at the truck today. Only code is an inactive Pid 84 for Road Speed Sensor. I pulled the Crank Sensor and it had no marks on it. I inserted a screwdriver thru the hole for the Crank Sensor and did not feel any looseness in the tone ring.

I will pull off the valve cover and, if necessary, drop the oil pan.

I will also check for crank end play. I have a pull clutch, so I will be levering the flywheel to the front.

patdaly

Shouldn't matter what style the clutch actuator is, the throwout bearing always pushes towards the engine to disengage the clutch, so that force will be trying to push the flywheel forward.

george7941

On my Freightliner, the clutch linkage pulls the thrust bearing back towards the tranny, so this will be the net force on the clutch/flywheel assembly, even if internally, the pressure plate "fingers" are being pushed forward to disengage the clutch. It is a Spicer Angle Spring clutch. My analysis may be wrong but I will find out which way the crank moves when the clutch pedal is depressed when I actually do the testing.

Now that you mention thrust bearing, the symptoms the engine exhibits strongly suggest a worn thrust bearing. Never occurred to me. Thanks. I will keep everyone updated.

I hope I can just drop the pan and change the #6 main bearing, which is the thrust bearing on the Cummins.

Clunk

Can end-play be checked at the harmonic balancer too?
Might be easier to get a dial depth gauge reading w/magnetic base.

george7941

The problem is trying to find something solid enough to pry against to move the harmonic balancer. Obviously the timing cover is a no-no for this purpose. i will see if I can use the cross-member supporting the engine at the front to pry against.

Clunk

I just though it would be an easy location to place the dial indicator, not to move the crank.

I agree all the prying should be at the rear.

Clunk

"The End play is minimum .004 and Maximum .017, normally they are less than .010 and more than .006. If you take out the sensor and reach in with a flat screw driver "GENTLY" see if the ring is loose, you will have to turn the motor over quite a few places as the ring has a one quarter cut out so you can remove it from the crank. It is mounted between the #6 rod and the # 6 main cap. It is called the Crankshaft speed indicator ring. We called it the speed timing sensor. If it is loose or damaged You have to remove the oil pan, and #6 rod to gain access to the ring."

Thanks jpringle3@hotmail.com !!!

george7941

Hi, guys! No progress to report. I pried on the clutch pressure plate and could not get the crankshaft to move at all. I even had a friend turn the engine over slowly with the alternator pulley while I tried to move the crankshaft to the front and I also stepped on the clutch pedal to pull the crankshaft back and there was not any noticeable movement of the crank. I don't have a dial indicator, so I don't know exactly how much end play the crank has.

Here are some photos that you might find interesting.

This one shows the pull clutch. On the right hand side you can see one of the two fingers of the yoke on the clutch linkage which moves the release bearing back to disengage the clutch. The tube running down from the release bearing is used to lubricate the release bearing.
http://i299.photobucket.com/albums/m...1/100_0220.jpg

This is the VP44. Easy to get to on this truck.
http://i299.photobucket.com/albums/m...1/100_0221.jpg

This shows the drivers' side of the engine. You can see that the crank sensor is very easy to access since the starter is mounted on the passenger side.
http://i299.photobucket.com/albums/m...1/100_0222.jpg

Lastly here is a view with the tilt hood up.
http://i299.photobucket.com/albums/m...1/100_0223.jpg

Enjoy.

george7941

Update. It wasn't the thrust bearing or the tone ring. It was just a defective starter which I will be replacing tomorrow. It looks like the starter bearings failed and that is causing the starter rotor to seize up. This led me to think the engine was binding.

Yesterday I pulled this truck with another truck and bump started the engine and confirmed that the engine was not binding. The engine is noisy but the noise is coming from a failing viscous clutch fan hub bearing . I will replace the bearing also tomorrow. That bearing isn't cheap, it cost me $142Cdn plus taxes at Cummins.

patdaly

Cool, glad to hear it wasn't anything really bad!