Anybody have this happen?

[ITSA426]

My 1967 440 lost most of its oil pressure while my son was borrowing the car.  I thought it had spun a cam bearing because I had no visible oil above the camshaft.  Engine idled fine but had lots of lifter clatter.  It wouldn't come much above idle but had enough power for him to nurse it about five miles home.  While starting a teardown I found the intermediate drive shaft broken at the base of the hex.  The oil pressure was right below the bottom of the normal arc.  I run a Melling high volume pump, which apparently still has the hex part of the intermediate shaft still in it.

Now I'm wondering how much of the engine is going to be reusable.  I have the correct 915 hp heads on it.  I haven't seen the camshaft yet but not optimistic.  I guess my biggest concern is what to do with the heads.  Any danger the crankshaft is OK?  This is a time I'm looking for good opinions.

I've got another 440 lined up but this engine was a correctly dated hp block so I'm a little bummed.  Advice?  The intermediate shaft was new with the build about 4,000 miles ago.  Never seen that happen on a Mopar.

[RallyeMike]

If it truly was 5 mins, the block and heads are probably fine, but opinions from afar have little value. I wouldn't give up on it - you're just going to have to tear it down and inspect.

[Kern Dog]

In 2006 I was coming back from the 7-11 several miles from my house. The engine started running rough and the oil pressure dropped. It was getting dark and I decided to nurse it home. A teardown revealed a broken RH rocker shaft! 4 lifters popped out of the holes, 4 pushrods laid in the lifter valley. I changed the cam and lifters, replaced BOTH rocker shafts and put in new pushrods. It ran great after that. I pulled the engine 5 years later to freshen it up. The rod and main bearings were fine but I replaced them anyway. The valve guides were fine. To recap, even with low oil pressure and driving 4 miles, the low rpms and low load resulted in no visible damage.
I probably got lucky.   

[GreenMachine]

I'd install a hardened shaft, change the oil, and run it. Check oil pressure hot and idling, if OK, I wouldn't worry about it.

I've seen a few of the hexes on stock shafts show signs of twisting on engines I've had over the years.

[heyoldguy]

Remove the oil filter and cut it open with a filter cutter. Look for engine debris in the can. Cut out the filter element and press the oil out and examiine the element for debris between the folds. Nothing in there? Replace the intermediate shaft with a HP one after inspecting the oil pump rotors for damage.

Customer brought me a set of cylinder heads from his truck with a small block Ford. Said, "Check these valves. I've had them redone from another shop twice. The guides must be too tight because they keep sticking and bending."

Nothing wrong with the guides, the other shop had done nothing wrong, and I told him so.

Brought me out to his house to look at a small foreign FWD car. Wanted to know if I could replace a piece of the aluminum block that the clutch knocked out when it blew up pulling away from a stop sign.

I said, "Who is driving when all this stuff happens?"

"My son."

"Uh huh," I say.

[BSB67]

I'd install a hardened shaft, change the oil, and run it. Check oil pressure hot and idling, if OK, I wouldn't worry about it.

This

[John_Kunkel]

I, too, agree; replace the intermediate shaft with a HP version and run it.  

BTW, all the shafts I've tested had the same hardness, it's the shape of the transition from the round shaft to the hex that makes them HD.

[ITSA426]

Thanks John, and everyone else.  Mine was the one on the left.  It broke right at the top of the hex.  Is there a separate source or part number for it?  I'll get the other one ordered ASAP.  No real harm in trying it out.  I've not seen this on a Mopar but a friend of mine had this happen on a small block Ford and it trashed his whole motor. 

Any problems to look for in the heads?  I'll pull the valley pan 'cause my kid brother dropped one of the little nuts off the coil down the distributor hole and we can't seem to find it.  That'll give me a chance to look at the cam lobes for anything obvious.

I wouldn't have thought to try to run it.  Thanks.

[heyoldguy]

Mopar Performance P3571071

http://www.manciniracing.com/mopbrbhemfla.html

https://www.summitracing.com/parts/dcc-3571071

[ITSA426]

Got it coming.  Thanks for the link.

[PRH]

Personally, I'm less optimistic that there is "no damage" done with the motor running for 5 minutes and zero oil flowing. And that's if the run time was really only 5 mins.

That being said, I think it's worth the time and effort to change the oil and filter and see what you find.

Since the oil pump wasn't turning/pumping, there should be no debris in the filter now.

What "I would do" is drain the oil now and look for debris in it.
If it came out looking okay, then I'd swap out the filter and refill with fresh oil.
Run the motor(with the new drive gear of course) for 15-30 mins, keeping an eye on the oil pressure.
Then pull the filter and cut it open, and see what's inside.

[ITSA426]

I like that.  Filters are cheap enough.  I didn't see anything obvious in the oil, but I'll check the pan when I dump it.  It never went to zero oil pressure.  The gauge stayed just below the bottom of the operating range arc.  As far as I know, the engine never went to high RPMs after that.  It would bog down with any serious throttle effort.  Lots of lifter noise and no oil spilling off the rockers.  I'm more optimistic than I was before, but I'm wodering about valve train damage.   I guess it's all repairable.

[PRH]

With the shaft sheared off, I dont know how there would be any oil pressure.
The pump is no longer turning.

The two times I personally have seen the shaft sheared off it was because debris got caught in the pump.
And both of those motors were "toast " as a result.
Badly scuffed pistons/bores, and wasted bearings and cranks that needed to be turned.

I forgot to mention, before I went ahead and slid that new shaft into place, I'd be checking to see how easily the pump turned with a priming tool.
It should feel pretty smooth and free of any binding.
If that passed the test, then I'd be sure to do a thorough priming of the system with the new oil and filter before starting the engine.

[ITSA426]

i think there was just enough binding on the shaft ends to allow some turning because I had some oil pressure.  no real marking on the broken end of the shaft.  I can look inside the cylinders for scoring without pulling the heads so I'll do that.  The engine didn't overheat.  I was going to just replace the oil pump and pre-oil the engine before cranking it.  I've now heard that I shouldn't have been driving a high volume pump with the stock shaft.  I didn't know that.  I'm wondering about the wisdom of high volume pumps an a street motor.

Valley pan is coming off next so that will give me a chance to look at cam lobes.

If nothing else this will give me a chance to do some detailing under the hood.  The car is in storage about 100 miles from me so I only get to play with it on weekends.  If I need to, I can throw in another 440.

[PRH]

Sounds like you've got a back up plan if necessary.

Definitely don't need the HV pump in that application.

[NitroNeal]

Ran for 5 minutes? Seems like it always took me about 5 seconds to kill my Dads stuff.