LSX_Burb

Hello all, I am a new member to the forum, but have been using this forum for years for information regarding various ls related items. I have a 1999 K1500 Chevrolet Suburban that is LQ4 swapped, but is currently down due to a blown engine.
I have recently acquired a replacement LQ4 core block over the weekend. Upon disassembly of the block, I found that when the number 5 rod broke, it caught the oil galley and made a small hole in it. Has anyone had any luck with welding a hole like this in a cast iron block? I feel very iffy about it being that the oil galley is under pressure constantly. Any and all help and insight is much appreciated.

mk3cn4

iTrader: (3)

(bug.. posted to wrong thread)

bthomas

iTrader: (1)

If I were to attempt that repair… I’d say best practice would be to clean the **** out of it, try to get as much out of the pores as possible.
Heat it up, a large area, not just the immediate spot. Oven would be best, but a propane weed torch would work too.
weld it with a nickel rod.
apply post heat
peen it with a needle scaler while still hot
apply heat again, and slow reduce the heat. Cover with a bunch of insulation to hold heat in. (This why an oven would be better and easier)

basically same process as welding up a cast diff.

Go back in with bore scope and find you welded closed the galley, drill galley out again…
Always worry about will it crack and leak some point in the future and kill new motor….

Long story short you’ll probably find it far easier to source another block.

RB04Av

Best way to repair that is a trip to the junkyard.

LQ4s are a dime a dozen. You can buy a good one for FAR less than it will cost to "fix" that one, then "rebuild" it. Cut your losses and move on.

grinder11

iTrader: (1)

Here's an opinion that may raise eyebrows!! Fill galley with oil, add 100 psi air pressure from the compressor, and see IF it leaks. If it does, where does the oil flow to, and how much? If it doesn't leak, your choice. Depending on usage, this block could be salvaged even if it has a small leak. Think about how piston oil squirters "leak" in 8 places, and you leak (maybe) in just one. Again, a LOT depends on how the engine will be used. Cast Iron CAN be successfully welded, IF you know what you're doing. If you're really set on welding it, stop asking here now, and ask these questions of a certified welder, one with a lot of cast iron welding experience. There are guys out there who could fix this. Like anything, good work isn't cheap, and it may not be economically feasible. My .02, and I've been wrong before......

RB04Av

This is the crux of the biscuit, right here.

Thimk of it like this: forget about whatever busted block you have. Zoom out to The Big Picture. Which is, you have a blown LQ4, and you want a working one to replace it. That's all that matters. Best path for you is the one that involves the least $$$, the least labor, the least time, and the least risk. Now, the $64,000 question: is jacking around with that busted block that you now have, and you have to buy pistons, at least one rod, bearings, rings, misc machine work, gaskets, lifters, ... the list goes on, ... The Best Path To Follow, given those underlying facts?

Put on your blinders. Blown-up LQ4 to working LQ4. Point A to Point B. Looking at the criteria I listed above (which of course aren't meant to be exhaustive, there may be others too) does jacking around with a bunch of scrap metal fit those?

Cut your losses on that s*** you got ripped off for. Hit the local buzzard nest. Pry em off of THE CHERRIEST LQ4 you can find. Hell, step up to a LQ9. Probably STILL cost less, be quicker, take less effort, and assume less risk, than messing around with ... that GARBAGE in those pics.

dixiebandit69

Please, good sir, tell me what utopia you live in where 6.0s go for a "dime a dozen.," and what does a "dime" in your money convert to in US dollars?

Nobody in my area will let a 6.0 go for less than a grand, and that will probably be a worn out, smoking wreck that needs machine work.

OP still has options, all of them less than $1K . First of all, he can find some thin tubing the same size or slightly larger, and sleeve the galley.

Next, he could drill the hole out larger, then tap it for a 1/8" or 1/16" pipe plug, then drill the bore out to get rid of the protrusion. I would never trust any weld to hold in that environment.

HEY OP: IF YOU DON'T WANT THAT BLOCK, I'LL TAKE IT.

DualQuadDave

iTrader: (6)

For a hole that big, I would drill and tap it and stick a set screw in it with serious epoxy on the threads. Would be a better repair than any welding.

You can use an angle drill to get in that space.

1FastBrick

iTrader: (16)

Get it magnafluxed first. I had one that had some minor damage similar to that. No cracks present. Instead of messing with it, I left it alone. Sold it to a some one that needed a block and last I heard it was running with out issue.

The other repair option was to ream out that port in the damaged area and Epoxy a brass tube in place that ends a little past the damaged area.

RB04Av

The US.

I don't have the good fortune to live in Texas though, where I freely admit, whenever I've been there and looked around, trucks are FAR AND FEW BETWEEN. Really quite a surprise. NOBODY has any kind of trucks down there, maybe they don't do construction or farming or hunting or anything? Iunno. Rarer than frog hairs for whyever. So I can see why LQ4s might be harder to come by down there than around here.

On car-part.com, once I get past all the "reman" ones for $4k, cores are $500. Running guaranteed good ones are $1500 or so up to $2k for a low-mileage one. I can't imagine how anyone could possibly have welding done on a block, then do anything remotely like a long-term-reliable rebuild on it even doing all the labor besides the machine work, for less than that. Or even close for that matter.

pdxmotorhead

My rube golberg version,,,
larger drill bit, drill through that hole into the block, tap and put in a iron plug with teh locktite that requires a plasma cutter to remove... .
Then use a long drill through the galley to drill through the plug.

Of course when I did this I was dirt poor and young and it was a 500 dollar truck... But it ran for 3 years till I sold it..