Big Block big time setback, cracked galley plug boss, anyone seen it before?

We we're scheduled to race at Eagle Field July 31st, completely rebuilt 454, .030 over, big solid roller, about 600 horsepower,, anyway, my son had the engine built at a central california race shop. After installing the engine and doing the fine tuning, it develops this big ass oil leak, in the vicinity of the rear main. So we thot,,,,,, after further review we find the cam galley plugs in the rear of the block had been drilled and tapped and in so doing we're cracked. I attempted to outline cracks with red...
Oil pours out of the cracks while we run the drill and pre-oiler at 65 psi.
So I present this dilemma to the many master engine builders on the hamb.
Anyone seen this before? I have not.
and the million dollar question is...
Can it be fixed or is the block junk..
This was a 2 bolt block converted to 4 bolt mains, not splayed, just a billet set
of caps.

 

plugs over tightened, doesn't look good.

 

it is fixable.... worth it?

best case scenario the engine has to come apart!!!

 

I hold out some hope of returning it to the race shop, but having them pay someone else to fix it, or replace the block, and then reassemble since my son paid them and the work was supposedly warrantied,, that has yet to be determined. We just found this tonight, and so he is going to decide how to proceed tomorrow.

 

If your machine shop tapped the plugs,and installed the plugs they are liable!!!! Bummer man sorry to hear. Its hard enough as it is to get your stuff out of machine shop jail,but to have this kinda stuff happen in the middle of a season just sucks!!!

 

I thought they all came with threaded plugs. This is a big block, not a small block.

 

Find someone that knows how to stitch repair,engine will not have to come apart and the method is very reliable. I don`t have the link but it is easy to find.Google cast iron stitch repair and go from there.

 

now that you mention it I think the small blocks are even originally theaded in the back right? Its just the front of the small blocks that come with the plugs from the factory??? either way..... If the machine shop took these plugs out as they should have.... they usually install them.. If they installed them its their deal. If you installed the plugs you might have yourself an uphill battle!!!! good luck!!!

 

They are out of Turloc Ca. should keep costs down. Good luck

 

to stitch that would require some kind of retapping. I would not repair this with engine still together!!! especially something that looks like he put a little heart and soul into....

 

Big Blocks all have tapped plugs, this was overtightened either this time or a previous time but it should have been caught well before now by whoever assembled the unit. Stitching will not work because the boss is cracked and stitching is used to fix cracked surfaces such as heads or blocks where there is a surface which cannot spread when the taper plug is installed.

The damage is done so what I would do is remove the plug and define how far the crack goes in and how much of material is left that may be tapped for a plug to be installed deeper into the lifter galley. You may be able to get enough threads and shorten up a plug enough to get a seal. Since this is a taper pipe thread you need but a few threads to create a seal. If there is enough to get some threads the broken boss can be shortened to allow the tap and plug to pass through.

Removing the intake and the lifter will give you access to catch any chips and putting wheel bearing grease on the flutes of the pipe tap catches a majority of the chips.

It appears as if this block has had a lot of machine work done to it that would not be repeated on a replacement block in time for your race so if the block is junk careful inspection and a bit of creative engineering could get this engine sealed up and ready to race.

 

Will post back when I have something definite,, still waiting,
I am curious and anxious as to what the outcome will be since I was hoping to drive the car
as well as my son..

 

It comes down to who installed the plugs......sorry to hear about it and i hope it all gets figured out this season

 

Pipe threads are tapered.
Tighten the plugs too much, and you see what happens.

 

grunt force trauma.....
Call the shop.
Tell them your are bringing the engine (intact) back to them.
(take your drill and oil pump drive adapter)
SHOW him where it is leaking ( he won't believe you on the phone)
TELL him you will be back (two days before the next race) and will be picking
it back up WITHOUT an oil leak.
Don't leave your drill or adapter......
Been there ( on both sides)
The engine will have to come apart. I used a lathe and cut down new plugs so they would not restrict the cross passage. Its a good thing he used pipe dope on the threads so they will come out. Install the plugs using a good epoxy to fill any hidden
cracks (most will be near the head of the plug though).
Before you take the engine re-test it with the drill and adapter.
On all of the BB engines I have worked on the plugs stick out between one and two threads......these are flush....bad bad wrenchman

 

Thanks for all the good info, but We have 0 confidence in the shop to perform the repair, hoping to have them pay to have it done at another shop, and or refund the total amount of the bill plus another good block wth all the work included.. looking at about 5 grand. We'll just have to wait and see, will post back when I have more info.

 

Why did you use them in the first place if no confidence in them? Is it a reputable shop or just a small shop doing work cheaper to get the business?

 

Shop choice was made by my son, it's his car.
It is a widely known shop in the central valley of ca..
I havent heard a lot about them, good or bad,
I do know that the mustang club frequents that shop,
While the engine was being built they called my son a few times to explain why the cost kept getting more and more. so not sure about reputable, not in my opinion,
wonder if they like ford's and sabotage chevy's,,

 

That actually might be a blessing in disquise. This same " race shop " installed the billet mains, meaning they drilled and tapped the outer holes, and align honed the mains when they were finished. Not only could this set back saved all of the bottom end of your engine build, could maybe have saved your sons life too. Those are definately tapped from the factory, and they have been installed way too deep. Sorry for this disaster you have had to experience. Maybe some members here can recommend a real engine shop, or you can check with some Cali. boat people/racers. They will have engine builders that KNOW Big Block Chevrolets. Best of luck. TR

 

I hate going out on a limb without seeing the block, but Ive saved more BBC's than most have built. A small pin hole at the end of the crack is first, to keep it from spreading. Dpeth here is critical, as you dont block any cross drilling. Now you would need to fill the existing hole with a cast iron plug like a Iron-Tite, using the correct tapered tap. This would be epoxied sealed in place and allow to dry completely. Now you can drill and tap for a smaller pipe plug. You MIGHT be able to use a 1/8" NPT plug. This might require using a 1/16" NPT pipe plug. It will be risky in the fact that the hole corner of the boss might crack and just fall out. Someone experienced and very patient should be able to repair this, again this is ONLY a educated gues without being there in person. My best to you and your son, TR

 

If you really want to save the block, you might strip the block, set it up in a mill and mill the area that's tapped for the pipe plugs down flat past the cracks. Then tap the galleys for a straight plug (I think you'll always have problems if you use a tapered plug in the damaged area) and use a plug with a gasket to seal the galleys. As said before the depth of the plug would be critical, check it carefully to make sure you aren't blocking one of the crossdrilled passages.
And no, I've never seen this done before. I've never seen a block with 2 cracks like that either.
Larry T

 

Looks like they were installed with a rattle gun ............................

 

That's a shame about the block. I understand you want to run soon. I would switch out the block myself. Got to be a bunch of good blocks out there. They are everywhere here. I'd bribe a reputable machine shop to do a block asap and assemble it myself. Doesn't take that long. Surely someone around there could help you out. Lippy

 

I have to agree here. It's very seldom that the one who damages something is fit to repair it. Also, as mentioned it "may" be possible to repair without taking it apart. Do that by having someone running the priming tool in the distributor hole while the repair is being made to insure an outward flow of oil to flush chips out as the repair is being made

 

To the O/P and those playing along, please dont think my repair was meant to do without a total disassembly. That was NEVER intended. Also, you mentioned " roller cam ", when you get those old plugs out, be sure to check to see if the " race shop " installed restrictors in those galleys. I think it could be saved. TR

 

Or a 36" breaker bar, and three RED BULL energy drinks. TR

 

I'm doing this in bits and pieces because I got stung in the face by a wasp yesterday, and I am very allergic, and I'm walking around sick and dazed and confused. The restrictors for the non Bow Tie blocks can be of 2 types. For one type you need to remove the cam and the rear bearing and look into the groove for the oil channel to look for the restrictors. Isnt bad, since you have to do a complete tear down to fix thir correctly and clean it all out. The second type of restrictor, well you might actually be looking at the back end of them. They are built into the galley plugs that your looking at that have been installed improperly. These are simply easier and not necessarily better. I prefer the ones in the oil galley groove, more work, the possibility of breaking a tap is very good, but a much cleaner job. This type also allows me the engine builder to decide what diameter hole to put in for the restriction. TR

 

Damn TR, sorry about the Wasp deal. Had one crawl in my coke can, I took a drink, got the little bugger in my mouth and he stung me on the roof of my mouth before I could spit him out. Lippy

 

Wow, sorry to hear about the wasp sting TR, nasty little buggers,
hope you'e feelin better,,
We get a lot of them round here too, I use carb cleaner to shoot em down and or kill their nests.

 

Those cracks could be TIG brazed by a professional.