My ongoing saga

[CJim7]

As some of you have been reading and offering advice/insight, I've been having issues with my freshly rebuilt 401. I finally got it running only to be confronted with some bad issues.

Anyway, I pulled the dizzy (thanks Cheapjeap) and a valve cover and checked oiling again. This time, as I spun the oil pump shaft with the priming tool, I got no oil to the rocker assemblies...

Odd I thought since I had checked all this beforehand and had primed the pump confirming oil to the rockers.

So I pulled the oil pump off and what would normally be one gear that slides onto the boss and another gear with the shaft....turned out to be not what I expected. The shaft had broken off the drive gear, rather broken free, and was not turning the gears.

I've seen this only one other time with a new set of gears, not on mine, but I guess it was my turn. I reinstalled another set of gears and reprimed the pump. Got good flow to the rockers. I still have yet to drop the dizzy back in and fire it up...

My only wonder is how bad is my engine screwed up now running dry

Dammit

 

[fishinfool98]

Hopefully you didnt run it long enough to mess anything up
i would do a compression test and see if any of them are have a big diffrence

did you do an initial compression test after the rebuild??

 

[CJim7]

Hopefully you didnt run it long enough to mess anything up
i would do a compression test and see if any of them are have a big diffrence

did you do an initial compression test after the rebuild??

No. Ironically, this engine had a complete rebuild about 3000 miles ago. Short history is that a wristpin froze up on me and scuffed up the #8 cylinder bad. I had it sleeved and replaced the piston. When I took the engine apart, all of the cylinders looked great...cept for that one.

The shop honed the cylinders for me when it was in there this last time and I insalled new rings.

My big concern running no oil like that is the bearings and cam lobes.

An update on all this is I got the dizzy dropped back in and fired it up and now (for the meantime) it runs great. Good oil pressure, no noise, etc.

I may have dodged a bullet on this one. Im firmly beginning to believe that this engine hates me.

 

[Petescj]

I hope you did. How long did you run it dry? Maybe it only broke free right before you shut it down?

An update on all this is I got the dizzy dropped back in and fired it up and now (for the meantime) it runs great. Good oil pressure, no noise, etc.

I may have dodged a bullet on this one. Im firmly beginning to believe that this engine hates me.

 

[Cheepjeep85]

Has it ran with good oil press. Before and did you still happen to have break in additive in it if so it might not have done any damage to the bearings or cam. Man id pull a main cap and see what the bearings look like, then id run it change the oil and repeat to make sure there aren't any left over metal pieces from the oil pump shaft

Sent from my DROID2

 

[Old Dog]

Has it ran with good oil press. Before and did you still happen to have break in additive in it if so it might not have done any damage to the bearings or cam. Man id pull a main cap and see what the bearings look like, then id run it change the oil and repeat to make sure there aren't any left over metal pieces from the oil pump shaft

I agree with Cheep, better safe than sorry. It will only take a couple hours.

I once had a engine that hated belonging to me, it finally comitted suicide idleing in the driveway.(poped a valve head that junked the piston & block)

 

[CRETE4U]

I think you dodged the bullet on this one. If you had much damage you'd probably know it. If it does bother you and it probably will, it wouldn't hurt to pull the pan and pull a cap for peace of mind.

 

[CJ]

Since 401's are getting pretty rare, I would definitely pull the main and rod caps and check them. Forged 401 cranks just don't grow on trees ya know...

Sent from my DROID.

 

[elwood blues]

^^^ CJ makes a good points, 401's are getting harder and harder to come by, if you've got the time...

My 2¢

 

[Cheepjeep85]

Have you figured anthing out on this yet?

Sent from my DROID2

 

[CJim7]

I drained the oil, pulled the filter and dropped the pan...checked for metal, came up negative. Pulled a couple bearing caps and they looked ok. Im running good oil pressure at this point.

As it stands, I either take the motor apart again or run it until I see an oil pressure problem. Right now the engine runs without any audible suspect noises...the real test will be under load. I have no desire to take this thing apart again. If I encounter an oil pressure drop, I'll know I took out some bearings and then I'll go from there...sucky as that will be.

But for right now, Im just going to put 500 miles on it, change the oil and filter, and see how it goes.


Still, the noise it made is bothersome. It's not a spun bearing, that's not something that goes away with the addition of oil. Not sure exactly what it was other then something got hot and expanded. It will probably reer it's ugly head in the future. But...Maybe I got lucky, who knows for sure at this time. :dunno:

 

[mylittlecj5]

We fired my Buddies CJ after he rebuilt his motor (first rebuild for him). We heard this screeching noise coming from the lower end. Stopped it and restarted it a couple times, but it kept making this weird noise.
Had good oil pressure the whole time.
He kept fretting about how much time he had into the motor, and "what if I did something wrong?!"
Finally located the problem.









It was the dust shield on the bellhousing rubbing on the flywheel as it turned. We relocated it and the noise stopped!

Just thought I'd relate a little story that has nothing really to do with your saga! :laugh:

 

[CJim7]

We fired my Buddies CJ after he rebuilt his motor (first rebuild for him). We heard this screeching noise coming from the lower end. Stopped it and restarted it a couple times, but it kept making this weird noise.
Had good oil pressure the whole time.
He kept fretting about how much time he had into the motor, and "what if I did something wrong?!"
Finally located the problem.










It was the dust shield on the bellhousing rubbing on the flywheel as it turned. We relocated it and the noise stopped!

Just thought I'd relate a little story that has nothing really to do with your saga! :laugh:

I've done that before. It makes a terrible noise

 

[CJim7]

Funny story, we were all out wheeling one afternoon and I developed a bad knock in the engine. I thought great....lost a bearing.

So we loaded the Jeep up on a buddys trailer and brought it back home pretty much expecting the worst.

crawling around underneath it, I noticed the dust boot missing where the clutch shift fork goes into the bell housing, but didnt think much of it. I pulled the metal dust cover off and a nicely sized rock fell out, one about the perfect size to fit through the hole in the bell housing where the boot should have been. Must have been ratteling around against the flywheel/clutch components. My buddy and I sat there thinking for a moment....there's no way.....

We fired it back up and it ran fine...