Hey All and thanks for any assistance in advance.

I have a '94 4Runner SR5 with the 3VZE. AT 4x4.

I bought this old girl about a month ago and have been chasing bad vibrations. I rebuilt & balanced the driveshaft, put new Koyo bearings in the front and new front disc rotors.

Things got better but the other day I heard a loud "noise-of-the-apocolypse" while on the highway.

It looks to me like the rear oil pan mounting flange of the actual engine block has cracked. There is a new oil leak there and I'm thinking I am looking at an improperly installed 2nd engine that the previous owner did.

Before I take this old girl out to be shot, I was wondering if there are any opinions about this.

Many thanks!

 

Is there an transmission/engine mounting bolt there? It looks like someone used the bolt to draw the engine and transmission together which is a no-no.

 

Not exactly sure where exactly to look but heading under there now.

 

Here's a couple of photos. Driver's side bell housing bolt is obviously totally loose.
It's backed out about a 1/4-inch.

Passenger side bell housing bolt looks ok.

Will have to get a socket on those to check.

I don't see where a transmission / engine mounting bolt would be in this area.

 

Yeah it looks like someone cracked it putting in an engine or transmission. If you look at the picture below, the bottom-right bolt hole corresponds to the cracked area of your block the best I can tell from your pictures. I don't think this crack is the cause of your oil leak though. Your leak could be coming from anywhere back there... valve cover gasket, rear seal, oil pan... etc.

 

Much appreciated.

I do not see the flange which is parallel to the ground which is broken in my picture.
Is this flange on the bottom side of the rear block picture you posted?

Does this basically mean a new engine / rebuild or at the least pulling the motor to fix?

Also, would the loose bell housing bolt(s) cause stress factors which could cause this crack (or some other nightmare) ?

 

Here is another picture. The bolt is on the passenger side rear of the engine. When the pan and other items are removed, you can see where it is parallel to the ground. The engine in this picture dirty so it is hard to see the bolt hole, but it shows you what it looks like with the pan off...

 

Yup.
I see it now. AWESOME.
I guess it's either a motor swap or the ol' girl is done.

Many thanks for your time.

 

I would not pull or rebuild the engine based on that one crack. There are enough bolts holding the two together that it won't make much of a difference. If numerous bolts were left loose, I could see how that would crack the flange, but I think the most likely reason for the crack is improper engine or transmission installation.

 

Would you just tighten the bolts and see what happens or what is your take on the next move?

 

That is exactly what I would do. I would tighten the bolts, monitor the oil leak and listen to see if that noise re-occurs. If the noise does come back, make note of the speed, gear or any other conditions when it happened.

I would also try to pinpoint the leak with an inspection mirror to see if it is coming from up high in the engine and dripping down or if it originates lower like the rear main seal or oil pan.

 

Thanks!

 

Some interesting finds while under the car:

Pretty much all transmission and bellhousing bolts loose. Looks like 2 bellhousing bolts are just missing.

And the winner is: The passenger side bellhousing transmission support bracket IS JUST NOT THERE. (I attach a pic of the part I got off the web).

No doubt the previous owner POS who did the engine swap must have cracked the block and then could not install the passenger side bracket - so he just stopped and put the car up for sale - and I fell for it.