Cummins Canoe (A Stepvan Story)

[PlethoraOfGuns]

The engine ran perfect! Even started down to 14 degrees f with no grid heater or glow plugs. But, it was low on oil, so I think we're going to blame that. The dipstick read good on the oil level, but when the oil was drained, only 5qts came out. This engine is supposed to have 10qts. We think it has the wrong dipstick in it. Too long of a dipstick. I paid cash for the van 6 months ago through an internet ad at a price which was a good deal at the time. Now, not so much of a good deal. And with diesels, there is no such thing as reasonable budgets...

 

[PlethoraOfGuns]

Engine out of the van, time to dig into this mess and make something go right.


It looks so lonely in there...

 

[PlethoraOfGuns]

Got the engine in the garage.


Time to tear this down and see what the issue is.


Took off the clutch and flywheel. Started a "part to keep" pile.


Showing off our confidence that we know what we're doing.


Diamonds, no wait, turbochargers are a girls best friend!


Flipping things over and going in.


Ah, there she is! Crankshafts are supposed to be one piece.


She still "ran", but it was very violent and broke both engine mounts.

 

[PlethoraOfGuns]

Dug deeper into our mess...


Went looking for a killer dowel pin.


And taking suggestions from others to fix the crankshaft, we're gonna give it a whirl. At this point, anything is worth a shot.

 

[Buddha.]

On the Deboss Garage YT channel he put a 4bt in a Tahoe. He said the 4bt is more unbalanced than the 6bt so he put a bigger harmonic balancer on it.
I wonder if broken cranks are a common thing with the 4bt.

How do the bearings look? Metal shaving in the oil?

 

[OverlandNA]

Cummins 4-390, 4B, 4BT 3.9L Crankshaft

Casting No. 3903827, 3907803, 3929036, 3908031, 91832

www.agkits.com

 

[PlethoraOfGuns]

The 4BT does vibrate more than the 6BT. Broken cranks aren't common, but they do happen. This isn't my first one. It does say made in Brazil on it, not sure if that has anything to do with it. This engine just had a normal crank pulley on it. We'll be sure to get a proper harmonic balancer on it when we get it back together. Bearings look a bit brown, but not melted. Lots of shavings and chunks everywhere. We'll need to hose it out with some hot water. Little bit of spraypaint, good as new. Hope the crankshaft fix will hold. We'll go easy and keep the rpm's down of course. New crankshafts are out of our budget. Have plenty of JB Weld and duct tape laying around though!

 

[OverlandNA]

There is at least one used crank on ebay now.

 

[hbabler]

Wait. You are planning on fixing the crank with JB weld? If so good luck, please let us know how that works out.

 

[PlethoraOfGuns]

Crankshaft was a pain to line up straight and set right with the JB Weld. We'll let it set up for a few days.


In the meantime, we're gonna need some new bearings. It looks like with the low level of oil, the main bearings were getting some oil, but not enough volume to get oil to the rod bearings.


Good news is that the rods and pistons are in great shape!

 

[Corneilius]

If you only JB weld that crank together you will be a legend. If it holds you will be a Hero!

 

[ITTOG]

If you only JB weld that crank together you will be a legend. If it holds you will be a Hero!

Close but no. If you jb weld it then you are not very smart. If it holds you will be a legend.

Sent from my Pixel 5 using Tapatalk

 

[Bikersmurf]

4bt Cummins Crank | eBay

Find many great new & used options and get the best deals for 4bt Cummins Crank at the best online prices at eBay! Free shipping for many products!

www.ebay.com

 

[dcguillory]

Obviously joking guys.

 

[PlethoraOfGuns]

Oh geez, ya'll are really putting the pressure on us! Now I'm not sure if the repair will hold. I guess maybe we can get a new crankshaft... ?