Repairing Drilled Engine Block

[DarkBlack]

Oh no... now you've started a whole "tape vs dope" debate, that'll take us through the next 3 pages.

…says the guy who posts every 5 minutes

 

[onetonford]

They might have picked that location because it has a oil passage thru there. If so no good to be repaired. Personally, I would not waste My time on it.

 

[manzer7]

I had the dealer install a new engine in my Kubota L4740 when it spun a bearing

In order to get the new engine from Kubota, they required the dealer to drill the block

Now I would like to rebuild this engine and am wondering what it would take to repair the drill hole

See pics

I would use J B Weld ! I've had good experience with it on my 1946 Willys CJ-2A Jeep repairing the front Head Bolt that got stripped. It comes out like cast iron ! If it is drilled right into the whole block - I would try it even inside the bore hole. If it doesn't pan out and provide the same finish in the cylinder then I would junk it.
THAT is my opinion of what I would do. Try it out ! Have fun at it . . . . . . .

 

[GeneSimm7]

Why did they want the dealer to drill the hole into the block?

 

[Page2]

Jeesh, why bother? You have a spun bearing, AND now a hole in the block! The bearing itself would be expensive to fix, and sleeving an engine is not cheap either. ---- Unless you are doing it yourself just to see if you can, then tear it apart and have fun!

 

[Gord Baker]

What is the concern with sleeving if into the cylinder?

 

[MRTOES]

Question....if the hole goes through to cylinder wall is it below the ring travel? If so thread the entire hole and insert threaded rod with sealer....otherwise junk it...
I personally would not buy a Kubota, no offense to anyone but they work too hard to do things like this. As another dealer at one time I saw too many small Kubota owners coming to me with tractors that ran hot with scalded piston walls and no sleeves....

 

[1Mech]

Looking into cost of sleeving it

How far down, from the top, is the hole drilled? If it is like halfway down, outside of the combustion chamber and below ring travel, why not just JB Weld it and give it a good honing, as long as nothing passes over it other than the piston skirt?

 

[1Mech]

So, once you spend the money to fix the "destroyed" engine, what do you plan to do with it, keep it as a spare or sell it?

 

[DarkBlack]

Jeesh, why bother? You have a spun bearing, AND now a hole in the block! The bearing itself would be expensive to fix, and sleeving an engine is not cheap either. ---- Unless you are doing it yourself just to see if you can, then tear it apart and have fun!

I’m still waiting to hear what bearing spun that deemed it more economical to replace the whole engine. Main, rod, or cam? Just one bearing? There’s got to be associated damage resulting from, and causing the spun bearing. Over reved, no oil pressure?

 

[sandman2234]

Maybe he is wanting to make some money on Craigslist or Ebay by selling it? Probably not, since he is considering fixing the hole in the block! A lot of those sellers just describe it as "Runs Good" and forget the hole! (Can you tell I recently had a bad purchase?)
David from jax

 

[heyinway]

Block is scrap. Most like Kubota, until Kubota does them dirty...then it's all $$$$. Once you ruin a Kubota block or head, it's scrap...not worth the cost to begin repair. Once they fail, they aren't worth the time or expense to patch.

 

[TheEquineFencer]

If it's a dry sleeved block, and the drilled hole isn't through an oil galley or water jacket, I'd take it to a machine shop. Machine a long cast iron "pin" and have them machine the end of it for the same diameter of the cylinder, heat the block, chill the pin and slide it in with red Loctite. You can have them machine "blank" the ID of the cylinder for a stop for the pin. Yeah, that's a lot of work, but I's still you block to do with as you want.

 

[POGuy]

If that serial number on the block is ever required for parts or service, there could be some grief for the "last one" holding the bag. Between that and an expensive repair process, I would be VERY WARY of going through with your plan. If EPA required them to do this, they (kubota) will be loath to get crossways with them (EPA). And do you plan to offer full disclosure to the next owner of that engine if it comes to fruition. I wouldn't do it.

 

[DarkBlack]

EPA…engine block serial numbers . Some of you guys crack me up with your government fear mongering about a little tractor engine. Be afraid… be very afraid

 

[5030]

Engine machinist/builder here.
The first move is to get it apart to assess if the rest of it can be machined and rebuilt.
The outside wall hole is not critical to operation or engine life if tapped and plugged. Don't over think it.
If concerned about the serial number when acquiring parts the aftermarket does not care.

It used to break my heart when Chevy would sledge hammer a perfectly good 427 vette block.

I dread to estimate how many perfectly good GM pickup trucks and Stellantis Vipers I ran through the crusher when I worked at a scrap yard in Detroit way back when. The crusher would render a good car into a metal cube in about 45 seconds. When we crushed them, there was always a rep from the auto company on site to make sure they were crushed.

Got to pick them up as well from the old, defunct GM plant north of Detroit and from Stellantis in Toledo. I'd go down and up with a 45 foot open top trailer and back up to the loading dock and they would literally shove them in head to tail until the trailer was full and it the last one didn't quite fit, they made it fit.

I saw lots of really nice vehicles get crushed. Only thing they lacked were tires and rims.

 

[WinterDeere]

EPA…engine block serial numbers . Some of you guys crack me up with your government fear mongering about a little tractor engine. Be afraid… be very afraid

Agreed. I'd be more worried and pissed about the time I wasted in rebuilding a questionable block, not worrying about serial numbers.

If you want a spare motor, I'd be shopping for one out of a junked tractor, before ever pouring time and money into a drilled block with a spun main bearing.

 

[POGuy]

EPA…engine block serial numbers . Some of you guys crack me up with your government fear mongering about a little tractor engine. Be afraid… be very afraid

Yep, it's all fun and games till the **** starts rolling downhill. There are a lot of "delete" manufacturers that never thought they would be held to account, but hey, you do you !

 

[Willie B]

Cast iron is a product full of challenges when you weld. Cast iron is porous, it isn't pure iron, there is a component of air, other impure gasses. Heat it to molten, there is a risk of poor fusion.
Then! you have a metal with low tensile strength. ALL welds shrink in the cooling process. A weld in the middle of the block will heat the existing iron very hot, It puts new metal in the space white hot. Everything hot will shrink. In the middle of a large block of iron with little tensile strength, shrinkage equalls cracks.
I would do all I could to avoid welding. Brazing is a choice, doesn't heat the cast iron as hot. I'd choose to avoid great heat. Tap the hole, put a NPT plug in.

 

[DarkBlack]

Yep, it's all fun and games till the **** starts rolling downhill. There are a lot of "delete" manufacturers that never thought they would be held to account, but hey, you do you !

Other than be fearful… I don’t get what you are trying to say.
We’re talking about a simple block. That’s it.
Not the exhaust, emissions system , computer system , injectors, heads, valve train…..

This or any other block could be built to be the most restrictive, stuffed up emissions compliant poor excuse of a diesel, or a rip roaring coal rolling powerhouse…..or simply brought back to what it originally was