The search continues...crankwalk?

[Dr. Marneaus]

So i crawled under the jeep with it running this morning and listened around for a while, I still cant pinpoint the sound, but i feel like I can hear it at the front and rear of the motor.

I turned it all off, pulled the flexplate/TC covers and took a good look at everything.

No wear on the flexplate bolts (i dont see how there could be, they sit behind the ring gear on the flexplate, and the flexplate is a good 1/2" away from the covers it seems?

The starter gear clears the flexplate completely, so thats fine...

I grabbed a screw driver and gently pressed the torque converter forward and back.

There is a tiny amount of play in there, I can feel it, it almost "sets" into place when i bry it forward with a teeny tiny "thud" (as it hits its limit of movement.

I held my hand on the harmonic balancer when i did this and could feel the same teeeeny amount of movement as well.

If I had to guess how much it moved (I had no real way of measuring) I'd say it moved maybe 1/32 of an inch. MAAAAAYYYYYYBE 1/16 of an inch at the absolute maximum.

Would this be a problem? Could this be making my tap tap tap tap knock rattle knock knock noise?

How much endplay is bad? should it have been 100% stiff?

Also, i saw a tranny bolt that looked like it had backed out a little, so i'll try to tighten that.

[The Colonel]

Crankshaft endplay should be 0.003 to 0.008 inch.

Got a dial indicator you check it with?

[Dr. Marneaus]

Originally Posted by The Colonel

Crankshaft endplay should be 0.003 to 0.008 inch.

Got a dial indicator you check it with?

No, i dont have any measuring tools other than a ruler.

This noise came outta nowhere though, and i find it hard to believe that it could have developed and worsened in the 1500 miles that I've owned it...

[The Colonel]

Originally Posted by Dr. Marneaus

This noise came outta nowhere though, and i find it hard to believe that it could have developed and worsened in the 1500 miles that I've owned it...

Which noise are you currently chasing-do you have a link to the beginning of the thread?

[Ristow]

if you can feel/hear it you have way too much.

my old 401 did this,the ring gear was hitting the bendix on acceleration.

[Dr. Marneaus]

So.....new motor then? New FSJ?

Will this one eventually just blow up? Not sure what this really means. Truck runs and drives 100% smooth and whatnot...just makes tapping noise at idle and when im coasting down only. Not under acceleration not when driving (atleast not that I can hear).

I'm not sure what would cause the actual noise though? Nothing on the outside is hitting anything that i can see, so, internals I suppose.

Sorry I'm such a noob.

List of problems continues...low oil pressure, endplay, leaks from everywhere...

[azpackrat]

The crankshaft end play is controlled by the thrust face on the third main bearing, so new main bearings may be in order. I wouldn't wait too long, I have a 401 crank that needs to be repaired because the thrust face wore too far and deteriorated the thrust surface on the crank. Pull the main and inspect the thrust face, it's a flange like side surface on the main.

[The Colonel]

Originally Posted by azpackrat

The crankshaft end play is controlled by the thrust face on the third main bearing, so new main bearings may be in order. I wouldn't wait too long, I have a 401 crank that needs to be repaired because the thrust face wore too far and deteriorated the thrust surface on the crank. Pull the main and inspect the thrust face, it's a flange like side surface on the main.

X2, if you catch it early enough you may be able to get buy with just new main bearings.

[Dr. Marneaus]

I have a feeling all of those things I need to do are beyond me, haha. Never done anything that invasive before...and well, first off...I dont even have a garage. Just a driveway.

[tgreese]

Sorry if this is blindingly obvious, but it's hard to own an old car if you can't work on it. If you really have a crank walk problem, you have a couple of options that do not involve replacing the bearings. You could pay someone to fix it, you could buy a rebuilt engine and install it yourself or pay someone to install it, or you can find a used engine and do the same.

In Las Vegas, especially going into the winter, I would not hesitate to yank the engine outdoors. I'd think it mostly depends on whether your neighbors/landloard/covenant permits you to taer down the car and keep it torn down for a while.

If you've decided it must be crank end play, I think the next thing to do is to drop the oil pan and look under the #3 main bearing cap. This won't be very complicated - drain the oil, remove the pan, unbolt the cap and look. You'll need a torque wrench to put it back.

[FSJ Guy]

I agree with tgreese. Easy to check the thrust bearing.

[Ristow]

you need to find the cause of the damage. and it's a slim chance the thrust face on tjhe crank isn't damaged.

it is more often caused by an automatic transmission,mainly a bad converter. not fixing the cause will promptly cause a repeat failure.

[WHSII]

These Gents can help you with the cause and effect of your Jeep problems, but I have an idea that might help you locate the exact point of the noise.

Take a broom handle from a push broom, (make sure it is a solid handle, out of wood) put it against the front of the engine, put your ear against the opposite end. Move the contact point in different locations on the engine, you will hear it get louder when you get closer.

This works very well locating the exact point of noise, such as when trying to find out if the bearings in the water pump are going out, or if it is the power steering, or alternator.

A poor man's stethoscope!

Hope this helps,

[Dr. Marneaus]

I've been using a stethoscope all over the motor and cannot pinpoint anything. Maybe i just have bad hearing, haha.

And i should clarify on the lack of ability and garage and whatnot:

What I mean is that I am 100% willing to dive into these bigger more advanced problems. I am enjoying learning everything thus far, as i'd never done half the things I've done thus far on the jeep. I love puzzles and problem solving, and in my mind the jeep is a big puzzle.

that being said, my issue currently is that i'm renting at my friends house, and there's a pool table where my jeep should be (a pool table that has never been used...but thats a different topic, haha). So, I more or less need to keep the jeep "together" I can pull stuff out that I can put back in weekends, but I'd prefer to keep it mobile in the long run.

Hopefully in a few months I'll be moving in with my girl, into a house with a garage ripe for the using! So, thus far i have been using my time to gain knowledge, and save money for some of the bigger projects that can come in the spring.

And end goal of my is to either get a 2nd 360 to rebuild, or rebuild the one that is in the jeep because that is something I have always wanted to do. I think it'd be an awesome learning process, as has been the rest of this ownership haha.

Anyway, I need an oil change anyway, so I might be able to drop the pan in the next week or 2. A new gasket probably wouldn't hurt either, haha.

Thank you all for the info, this is pointing me in the right direction, and I know I say it a lot, but I'm sorry for being such a noob and asking so many questions, and thank you for helping me along my way. I'm gaining more confidence in my mechanical abilities and knowledge every day.

Is this a loud rattel clank noise? I bought my last jeep with the same noise almost like it was going to come apart on idle.. It was the flex plate.. It was Cracked around the mounting bolts. Sounds almost like your problem....

[CJ5]

Originally Posted by bigblock91

Is this a loud rattel clank noise? I bought my last jeep with the same noise almost like it was going to come apart on idle.. It was the flex plate.. It was Cracked around the mounting bolts. Sounds almost like your problem....

That is a good start. Same type noise on my 03 Suburban. It would tick at idle. I couldnot hear it any other time. Then I begain to hear it coasting and idle only. Upon investigation, the flexplate had all but separated from around the bolt holes.

[Dr. Marneaus]

Its a rattly tick.

I have looked at the flexplate several times, but I've yet to actually "inspect" it.

This weekend I'll remove the bolts (which i have tightened) and teka another look, as well as hit it with a wrench to see if it rings or thuds.

[CJ5]

Originally Posted by Dr. Marneaus

Its a rattly tick.

I have looked at the flexplate several times, but I've yet to actually "inspect" it.

This weekend I'll remove the bolts (which i have tightened) and teka another look, as well as hit it with a wrench to see if it rings or thuds.

The ones I have seen that have cracked tend to crack between bolt holes. The crack runs from bolt hole to bolt hole and in my case it was cracked from and to all but two so when the were removed the plate fell off.

Mine was cracked around the outside of the bolts. The flex plate fell in to as soon as it was removed. I had a rattely click to at idle not under load

[azpackrat]

Even if the flex plate is cracked and that is the source of your noise, a sixteenth of an inch is excessive end play for a crankshaft when you consider the correct tolerance is measured in thousandths of an inch. My advice would be to check the bearing regardless of the source of the noise, it might save you the expense of repairing or replacing the crank.
As far as being a noob and asking too many questions, we were all noobs once and somebody else answered our questions, you can't learn if you don't ask.