Also: I notice that there is an oil filter adapter, and in some cases it also holds the sensor. I'm a few miles down the road right now, but I might pop over and look at it, since it would be GREAT if there's an adapter that broke, instead of the block. I would have thought I would have noticed that, though...

 

If the block is cracked in an oil passage, it is done for. The crack can be repaired, but the block would need to come apart and be well cleaned.

I'm not sure if the oil filter adapter ever holds the sensor. They usually are only there on the vans that had an oil cooler.

 

Hmm. Well, the crack appears to be in the fairly thin band of block just above the oil sensor: does that make sense to you? But yes, I would assume any welding would reguire the engine out and apart, which is probably more than I can reasonably justify...

To be clear: when you say "van" are you including the T&C, or no? I think no, if I understand...

 

Yeah, the caravans and T&C's had optional oil cooler. If the crack is in the block, it would be much easier swapping the engine with a used one vs repairing the original one.

 

Hmmm. Seems like a new engine is going to cost $800-$1500, and the install will definitely take it over the cost buying a new van: $1000 labor?. No? I don't have the time, and I have somewhat marginal skills/patience, to do an engine swap. Would it really make sense?

 

The sensor has pipe thread on it, you can try taking in back out, put a few turns of teflon tape on the treaded part then just threading it in finger tight. You might find that this will still seal up at the tread and will not wedge the crack open. Just thinking aloud.
Hank

 

thanks, I sort of tried that. In fact, it may be that the crack has been there a long time, but forcing the sensor too far in forced it open. Anyway, it's not workable now. Also, I checked and it is in the block itself. I didn't even think to warn my helper not to put his weight into it, and I was doing other things. Ugh.

 

Engine aside, what kind of shape is the rest of the van in?

 

Another trick I have used to fix leaks in castings is to use a pin punch and gently pean the metal back to close the crack or pinhole. Put the sensor in first with fresh teflon tape it doesnt have to be very tight to seal up. then GENTLY try to pean it. As you gently punch the metal in it will close the crack. At this stage if you have confirmed it is a crack this may be your only hope to save the block without removing it cleaning it and then welding it. The crack has to be completely free of any trace of oil for welding to work. Then because it is cast iron it should be preheated as well to prevent more cracking. I am a millwright by trade specializing in hydraulics and have done this with success in the past.
Hank

 

take the vehicle to a shop that does block stitching. Maybe they can help you. call your local cummins dealer and ask them for a recommendation. they had a problem a few years back and a lot blocks needed repair....

 

The above methods are the preferred method. I've also seen a $6.99 tube of JB Weld fix cracks too. For the price, sure worth a try.

 

Stitch welding a coolant passage is usually an acceptable fix, but one in an oil gallery is never anything I would trust. Getting it clean enough to weld would require hot tanking the block as even if you clean the outside, oil will wick up the crack when the welding heat is applied. Something like this would make a vehicle not to be trusted for anything but short trips. No one likes an engine failure, especially when far from home.

 

Stitch welding a coolant passage is usually an acceptable fix...

Andy, it's not welding.....

http://www.locknstitch.com/fix_cracked_engine_block.htm

This is done as a last ditch effort. Works sometimes fairly well on cast iron. All depends on the skill of the "stitcher"...

 

Well, on further consideration, I think the block was cracked when I bought the van. I realize now that the previous oil sensor was not inserted very far, and that (despite there being oil all over the place, including dripping off the sensor from the leak above), the sensor threads were clean. When I back out the sensor, the crack mostly closes up, and the leak becomes sorta minor (well, my guess is it will be a quart/month, but I haven't seen yet: before, it varied from indetectable to 1/2q/mo, perhaps).

Alas, replacing the engine isn't worth it to me, and I can't really live with this kind of problem (it'll bug me too much). So I've gotten a different minivan (Honda Odyssey 2001) which I'll be getting into shape, and then selling the T&C. Thanks for everyone's help, this is a great site, but I'm probably signing off. Enjoy your T&C's!

 

Is the rest of the van in great shape? If it is it might well be worth putting a used $400 engine in it, even if the labor costs over $1,000, and then selling it.

 

Interesting comments, btw, on "metal stitching": I don't think it would apply to this case though: the area of the crack is highly non-flat, and too inaccessible to do in place without LOTS of parts removal, so it would still be quite expensive (in either time or money). Still it's an interesting approach.

 

No: there's not much rust, but it's SERIOUSLY banged up. I bought it for cheap ($1300), and it looks like it might have been rolled once (a couple big dents on the roof where there shouldn't be). Then I had a minor front ender, but enough to require a new radiator. I popped in a new water pump while I was at it, I had to replace both axles for inspection, I just did the valve cover gaskets, oil pan gasket, and 3 of 4 tie rod ends... oh well. As far as I can tell, I've got the oil leak back to where it was, which is miniscule: maybe a quart every few months. The big ordeal is that I have a mystery coolant leak which I thought I finally found by pressurizing the system -- the thermostat housing gasket -- but I've fixed that and I think it's still leaking. It looses about 1-2 quarts almost immediately, and then stays there. Never overheats. I had a shop look at it, they pressurized it and dyed it and couldn't find it either.

 

Given the condition of the body you're probably right; it isn't worth a whole lot of investment. Regarding the coolant leak, I'll lay odds the issue is one or both "O" rings in the timing chain cover which allows a small amount of coolant to leak into the oil pan (very bad for engine bearings).

 

Find someone that has a welder (knows how to use it) and a torch. May as well have them hit it with a nickel rod while heating the whole area and see what it can do. Or junk the thing lol. Dents on the roof bay be from people dancing on it, my van has a similar condition from that reason... If it were rolled, nothing would really be right in any body gaps or doors closing properly.

 

J-B Weld has done amazing things. Worth a try for sure. My Neighbor has used it successfully on the transmission, I believe, for his 1953 ex-military Dodge Power Wagon.

 

Yeah, maybe it wasn't rolled.

I think the leak is in the radiator. It's a new radiator, only a few months old. But I've noticed 1) it only leaks down about 4 inches, no matter how long I let it go before filling (and it leaks down that far quickly), and 2) there's often some trace of fluid right around the cap, even when I'm VERY careful to fill it without spilling. However, under pressure (20 psi) there's no discernible leak. Very strange. New radiator cap (though the old one appeared fine) and no clog in the tube to the overflow (I can blow through it).

The radiator is one with plastic ends and Al fins/tubes.

 

4" from the very top?? That's not so bad (very small quantity) and likely due to air getting sucked into the system during cool down, most likely from the overflow/reservoir piping. Does the level in the reservoir increase after each time you top up the radiator? In other words, is the system actually losing any fluid.