Broken Bolt Holes on Engine Block

[jtl]

Hello everyone! I'm new here, though I've been poking around the site for several months now.

I bought a '97 (correction: ‘96) Mazda B3000 back in April. I love the truck but I guess I did a terrible job vetting it. Here are a few highlights:
- The head gasket had failed and someone used head gasket sealer before my dumb ass bought it... now the heads are warped
- Oil leaks from just about everywhere other than through the block itself
- The headliner looks like someone threw a stray cat in there then set off a firecracker (I knew about this one of course, but I think it's funny regardless)
- The driver side of the engine wasn't even attached to the engine mount

I'm quite cheap resourceful so I am fixing as much as I can. I got the engine out of the truck today and confirmed that one of the engine mount bracket bolt holes is broken off the block. I also learned that a second bolt hole is also broken, though I have no idea what it's supposed to be attached to.

My two questions:
1. Is it feasible to repair these without replacing the engine block, or is there a way to mount the engine securely without that particular hole?
2. The broken bolt hole on the left is for the engine mount bracket, but what bolts into the broken bolt hole on the right?

I need to purchase some replacement heads already, so depending on how much of a problem these bolt holes are it might be worth it to just replace the whole motor.

 

[ekrampitzjr]

Replace the engine. You'll never be able to trust a repair on something like that bracket bolt hole.

You also don't know whether replacing the heads is going to fix everything. I doubt it will. For those bolt holes to have broken as they did suggests something violent happened inside the block that you haven't discovered yet.

 

[pjtoledo]

are there any threads left in the mount hole?
depending on how deep the hole is you may be able to use a bottom tap and thread it all the way to it's bottom, then use
a matching bolt that tightens up just before it bottoms out.

I have a broken mount hole in my 2000, a used engine, been fine for the last couple years. I don't do crazy stuff,,,,yet.

the hole below the filter is for the starter & funnel/oil spill thingie.

the oil pan gasket is not factory.

the 3.0 is an easy engine to rebuild, can be a good learning experience so open it up and check it out.
get some plastigage for checking bearing clearances.

 

[don4331]

The only thing I can think of for the broken front bolt mount would be the power steering pump; The 3.0 doesn't have the anti torque shock found in the 4.0.

My guess: this is the 2nd engine in the truck... The 1st one died and this is replacement. And this engine came from a truck which had been hit on driver's front - that would explain a hit hard enough to damage both the block and the oil pan. ( I would check your truck's frame but a hit that hard would normally be a total loss). Alternately, it could be a transverse block from a Taurus or Windstar; I don't know how they mounted accessories. But I know you can use the transverse block as a starting point for a Ranger.

Then when this engine was installed, they didn't get all the air out (3.0 in challenging to get to burp that last bubble). Hence, the overheat/blown head gasket.

I'd be going with @ekrampitzjr and get a new long block, if not whole engine. By the time you get all the parts, its more expensive (unless you really want the learning experience)

 

[Brain75]

If you enjoy driving more than wrenching, go to the junkyard and get a like for like replacement - swap it in a weekend and you can start enjoying your truck again instead of having a project occupying the shop for a year while you get parts, wait for machine shop, etc

 

[SenorNoob]

I had the same problem on my original 4.0. I'm inclined to agree with don4331. That engine came from a wrecked truck.

 

[jtl]

Thanks for the help everyone. I ordered a used replacement from a junkyard but it had the same damn problem - actually slightly worse, I think all three were broken! The guy had it shipped back to him then had one of his guys weld it. I guess time will tell how it holds up.

Now I’m replacing all the old gaskets and seals and timing chain before putting it in my truck. The color inside the coolant ports is concerning me. I think it’s rust but I can’t shake the feeling that I just replaced my old engine with another one someone dumped gasket sealer into.

Would someone mind looking at this please and telling me how bad things are?


Maybe I should have just bought a crate engine…

 

[pjtoledo]

coolant passages all have rust in them, yours doesn't look too bad.
going back to your first picture,,,
just below the freeze plug is a small plug. that's the bottom drain for the water jacket.
I would remove that and flush the crap out of the lower block. other side too.
unfortunately they can be very difficult to remove.

 

[jtl]

coolant passages all have rust in them, yours doesn't look too bad.
going back to your first picture,,,
just below the freeze plug is a small plug. that's the bottom drain for the water jacket.
I would remove that and flush the crap out of the lower block. other side too.
unfortunately they can be very difficult to remove.

Thank you, that’s wonderful news.

Is there a trick to these coolant plugs? The first one rounded out so I hammered a torx socket into it and that held well enough to remove it. Then I bought a better set of Allen sockets to get the other side and to remove the same plug from the old engine to replace the rounded one from the “new” engine. 1/4” seemed to fit perfectly but it is also rounding out. 7mm is loose but 8mm is too big.

 

[jtl]

If you enjoy driving more than wrenching, go to the junkyard and get a like for like replacement - swap it in a weekend and you can start enjoying your truck again instead of having a project occupying the shop for a year while you get parts, wait for machine shop, etc

Somehow it’s still turned into a project lol. I replaced the motor mounts “along the way” which led to replacing u joints in the axles, new ball joints and new tie rods since they’re “along the way” to the mounts, new reman steering gear to because the old one leaks badly and the engine is already out so it’ll be easier. I had to stop myself from buying new leaf springs because “it’s already up on jackstands so I might as well.”

 

[Brain75]

I keep looking at the little tiny spot of oil on the cement and saying "one more thing" ... and I am not even done putting it on the road after paint. It's almost entirely re-assembled, just a few interior pieces while I do electrical work (added 3rd brake like, separated cargo light to it's own switch - that is continuous power, added fog lights, upgraded 9004 to 9007 headlights..... all that list was "since I have it torn apart to paint" was the only reason).

 

[Brain75]

I also didn't figure you would be forced into a junkyard motor "from inventory" sight unseen... I keep forgetting that it seems nobody else has a u-pick-it where they can look at the odo, see if the engine bay has ANY intrusion, etc before even considering that motor as a candidate..

 

[pjtoledo]

Thank you, that’s wonderful news.

Is there a trick to these coolant plugs? The first one rounded out so I hammered a torx socket into it and that held well enough to remove it. Then I bought a better set of Allen sockets to get the other side and to remove the same plug from the old engine to replace the rounded one from the “new” engine. 1/4” seemed to fit perfectly but it is also rounding out. 7mm is loose but 8mm is too big.

they stick in there real good. I've destroyed tools and a plug or two.
If memory serves me correctly, they are common pipe threads. I would have to check to be certain. can anybody verify ????

 

[jtl]

I also didn't figure you would be forced into a junkyard motor "from inventory" sight unseen... I keep forgetting that it seems nobody else has a u-pick-it where they can look at the odo, see if the engine bay has ANY intrusion, etc before even considering that motor as a candidate..

“Forced” is a strong word. A friend recommended car-part as he’d used it in the past for a transmission and some other stuff for his car. The one I did grab had no pictures but 126k or so miles and a 90 day warranty so I figured I’d risk it.

 

[jtl]

they stick in there real good. I've destroyed tools and a plug or two.
If memory serves me correctly, they are common pipe threads. I would have to check to be certain. can anybody verify ????

My bolt sizer matches it with M14-1.25. It threads in all the way but feels a bit loose in there, probably because the sizer has no taper like pipe threads.
I ended up using the same method to remove both: hammer in a torx bit after the 1/4” allen deformed it, then remove it like a normal torx bolt. They’re reliably torx now so I think I’ll just use them as is lol