Well I guess this block is toast

[Zambo]

Hauled the 400 chevy sb out of the old rustbucket truck I just bought. Well I was putting it on the stand and when I was tightening one of the stand bolts, the damn corner of the block cracked off where the bolt hole was. Its the hole right next to the oil filter. I'm guessing this thing is junk (no great loss though, this motor was thrashed anyway), but I figured I'd put a pic out here so the local experts can add their two cents as to if you can fix something like this or if its even worth it. Sorry for the crappy pic.

 

[Ziggy]

You may be able to get a remote filter to spin on there and just move the location.

 

[Zambo]

Well the problem isn't really the filter, the seat is fine. I'm worried about mounting the transmission without that bolt boss there.

 

[bigone721]

I wouldn't even worry about something like that, I've ran lots of engines with only a couple bolts holdin' the engine and the trans together and never had a problem. If this did scare you though you could run some braces from the trans to the engine like the factory uses on 4X4s.

 

[Zambo]

Well if this motor was built I wouldn't hesitate to put it in the truck, but this thing is completely thrashed and needs to be rebuilt all the way. Would you spend money to rebuild a motor with this block I guess is a better question.

 

[lstrong]

No, I have seen transmissions break bell housings that the bell housing were not tight enough.It's not even worth the small chance something could happen.

 

[Dezertpilot]

It can totally be fixed, I posted a small video from Brodix and the repairs they have done on cylinder heads is AMAZING! But the entire integrity of the block might be in question, is their a lot of rust running through the water jackets?

 

[Zambo]

It can totally be fixed, I posted a small video from Brodix and the repairs they have done on cylinder heads is AMAZING! But the entire integrity of the block might be in question, is their a lot of rust running through the water jackets?

Where is that video? I haven't pulled the heads yet but looking into the journals where the intake manifold was I can see rust inside the heads so I'm guessing its in the block too. I'm no expert obviously so I don't know what is a lot of rust and what is normal.

 

[Dezertpilot]

http://www.brodix.com/repair/repair.html

Here it is!

 

[Zambo]

Wow, I wonder why someone would choose to do that rather than just buy a new head, that can't be cheap.

 

[Dezertpilot]

No I bet it is $!!! But if your heads already are fully P&P'ed, plus a bunch of other high end add on's it probably makes it worth it. But the one shot of the corner fully missing that blows my mind how they fix it.

 

[partybarge_pilot]

If you still have the piece that broke off it's an easy fix.

 

[Zambo]

If you still have the piece that broke off it's an easy fix.

I do have the piece, its just one hunk, it didn't crumble or anything. How do they fix it? Just weld it back in, redrill and tap the hole?

 

[scottm]

It can be welded, but the strength of the block will be in question. The lower bolts are in tension from the weight of the engine and transmission, and repared cast iron is not known for good tensile strength. A midboard engine plate will take care of it.

The sbc 400 has a reputation for overheating and cracking the block, particularly around the steam holes between the bores. There is nothing wrong with the design, its just that the average user does not change coolant enough, resulting in rust clogging the steam holes. Dont waste any effort on a repair until its stripped and inspected.

The 400 is an excellent engine, and I have two - one is a stock bore with a 350 stroke BRC crank, which makes a high rpm 374. The other is a 030 over, fully prepped block that is going to get a stroker 400 crank (3.875 stroke) to make a torque monster 416. I don't have any concerns of overheating when its done. Just always run purified or distilled water with good coolant or Water wetter (coolant is better for corrosion protection and water pump life).

 

[partybarge_pilot]

I do have the piece, its just one hunk, it didn't crumble or anything. How do they fix it? Just weld it back in, redrill and tap the hole?

Chamfer the pieces, bolt the block to a bell housing. Stick the piece back where it belongs and weld up. If you have bolt in the hole when you do it the threads will line up.

 

[Zambo]

Thanks for the input fellas, I'll letcha know how it turns out.

 

[Zambo]

One other thing I've learned about this motor is that the 400 seems to stir up a lot of controversy! Everybody I've talked to thinks its either junk or the greatest damn thing since sliced bread.

 

[bajaruner11]

The locating dowel pin is still in place, so I would not be concerned with the fact that one bolt hole is bad.


I would be more concerned with the fact that you have a 30+ year old block on your hands that you may
try to rebuild, it's hard to come by good used 400's anymore. The majority are cracked anyway along the deck
around the water jackets, not to mention the fact that there only good to +.040" over bore. So if it has been
rebuilt once before, it's a goner anyway.

 

[JEFFRPM]

Send the thing to the machine shop get it tanked and magnufluxed if the deck and the main webbing have ANY cracks toss it in the dumpster get a world block their cheap compaired to the dart or brodex ones.

 

[Dezertpilot]

World, I think it is just came out with a brand new 409 aluminum block. It is in the new Hot Rod magazine. Imagine that block bored and stroked