Engine Rebuild gone wrong?

[new-to-engines]

Hello all, I'm currently in the process of rebuilding a Kubota D600 block engine, mine is actually the marinized version (Universal M3-20) but it's still a Kubota block so I was hoping I could come here for some help. I believe this engine block was mainly used on the G5200.

In removing my last freeze plug I ran into some trouble getting it out and began to drill through it but I made the huge mistake of drilling partly into the cylinder wall, I'm kicking myself but coming here to see how disastrous it is. I have attached a photo below I don't have a great sense of how deep it goes in, it is not into the cylinder wall but I'm not sure how much thickness is left. I'm going to take it to a machine shop next week to see what they think but I've got a few questions below, welcome any thoughts thanks!

1. What are the repair options? Will they be temporary fixes or leave me with long term issues?
2. It looks like I can get a new block on Ebay for $500 is it worth taking the risk of a repair or should I just opt for a new block?

 

[lynnmor]

It might be OK, take some more photos and try to get in focus at the drill mark, the current photo is too far out of focus to give a good diagnosis.

 

[GeoHorn]

I’ll go out on a limb and say you’re probably all right. I’d epoxy that tho’ to guard against corrosion.

 

[acruxksa]

Not to make light of your situation, but essentially it will be fine or it won't.

Seems like one of those situations where you should just see what happens before throwing the baby out with the bathwater.

As I see it, you got a few options:

1) ignore it and see what happens.
2) attempt to braze or weld the divot.
3) throw the block out and replace it.

I'd ignore it, then if it is or becomes an issue, attempt to braze/weld it (or have someone else attempt it) and finally if neither of the above work or the weld/brazing repair cracks the block further replace the block.

That being said, I know nothing about repairing damaged engine blocks, but did stay at a Holiday inn Express once. Also, I have a lot of experience dealing with my own mistakes. They happen to everyone.

 

[Kubota Newbie]

Welding / brazing - no, iron block, it'll create a hard spot on the inside of the liner. Will likely crack.
Epoxy - maybe, if a really good industrial grade. Heat transfer might be different.

That appears to be a sleeved block so there's no real issue with combustion sealing after you replace the sleeves. If that's the case and you didn't go through the block liner, chamfer the edges a little, install a new sleeve and move on.
If it's not a sleeved block well then you have the option to epoxy it and hopefully it is still thick enough to be ok, or, put a cylinder liner sleeve in it.
If it's a sleeved block and you went through the liner, and, if you didn't make too big of a hole, a good automotive machine shop could probably put in a tapered cast iron screw used to fix head cracks and it'd be ok.

 

[DustyRusty]

Clean up the area around it with sandpaper and put a dab of epoxy on it. To me, it doesn't look deep enough to do any damage.

 

[Runs With Scissors]

Hard to say from that pic, but it doesn't appear to be too deep to me.

If it were me, I would just leave it alone.

I think the epoxy thing has the potential to cause more harm than good.

I don't know of any epoxy that would actually add any amount of "structural integrity", and having a chunk of epoxy swirling around in my cooling system would not give me a "warm and fuzzy" feeling.

 

[GreensvilleJay]

curious, so found this for the block. Where is the drill scuff ? Front 'face of block ? I agree not 'deep',probably not a problem but...
What's the part with orange paint you drilled ? I can't see which 'depression' it is.
If really concerned, clean off the rest of the paint in the 'depression' and FILL it with a good 'metal' epoxy. Allow to cure for at least 3 days at room temperature.

 

[chim]

Since nobody else mentioned it, I guess there's nothing to it but when I zoomed in it looks like a smiley face shaped crack from the left side of the drill mark? Casting mark?

 

[hodge]

Your machine shop will be the best judge of whether it's an issue or not. I'd wager that it'll be fine like it is.

 

[fried1765]

Clean up the area around it with sandpaper and put a dab of epoxy on it. To me, it doesn't look deep enough to do any damage.

DITTO !!!

 

[D2Cat]

If you fill it with epoxy you'll need something to hold it in place as it dries. I'd use a piece of duct tape.

 

[The Evil Twin]

The problem with using am epoxy (Locktite Metal Weld) is that the surface needs to be exceptionally clean. Otherwise, it will not bond well. Personally,

 

[GeoHorn]

Whenever I need a clean, no-residue surface….This is the stuff I use. (also it’s safe for plastics
Walmart or Amazon, etc. about $10

 

[new-to-engines]

Thanks all for the replies, took a better picture which probably can only do so much still. I did my best to try and get a rough measurement and think a conservative estimate is 2mm but probably a bit less than that. Measuring the distance from the inside of the sleeve to this wall I'm getting somewhere between 4mm and 3.75mm. So with that is 1.75mm enough thickness?


EDIT: Also it is a sleeved block so it sounds like if I get it resleeved then this won't be an issue. I'm taking it to a machine shop later next week to see what they think. Depending on what they quote me I may end up with a new block as I can get one for $500. This is my first engine rebuild so not sure what to expect in prices from the shop.

 

[new-to-engines]

curious, so found this for the block. Where is the drill scuff ? Front 'face of block ? I agree not 'deep',probably not a problem but...
What's the part with orange paint you drilled ? I can't see which 'depression' it is.
If really concerned, clean off the rest of the paint in the 'depression' and FILL it with a good 'metal' epoxy. Allow to cure for at least 3 days at room temperature.

Yup it's the front face it's the freeze plug hole that lines up with part 40 on the diagram

 

[North Idaho Wolfman]

It does not look like you hit the sleeve, so I don't think resleeving it would do you much good.
I would have the hole mig or tig welded or even just gas welded and call it a day.

 

[Vlach7]

Small wire or rod, minimal amps to decrease penetration/damage.
Keep us updated what you do and how it works/lasts.

 

[Flintknapper]

It does not look like you hit the sleeve, so I don't think resleeving it would do you much good.
I would have the hole mig or tig welded or even just gas welded and call it a day.

^^^^^^

This.

The only secure repair would be to braze or weld the void.

The intent being to prevent a 'crack' from developing later. It isn't a matter of strength (the cylinder bore is sleeved). But if a crack were to start, no telling what might become of it.

Trying to fill a tapered void with an epoxy product is not likely to be successful or stay put. The different expansion/contraction rates of the materials (cast iron vs. epoxy) is almost a guarantee it will break the adhesion over time.

Cast iron can be welded or brazed (with pre-heating).

 

[The Evil Twin]

^^^^^^

This.

The only secure repair would be to braze or weld the void.

The intent being to prevent a 'crack' from developing later. It isn't a matter of strength (the cylinder bore is sleeved). But if a crack were to start, no telling what might become of it.

Trying to fill a tapered void with an epoxy product is not likely to be successful or stay put. The different expansion/contraction rates of the materials (cast iron vs. epoxy) is almost a guarantee it will break the adhesion over time.

Cast iron can be welded or brazed (with pre-heating).

Yup. Back in my days as a field steamfitter, I would weld cast iron all the time. Don't use TIG, as localized heating is too high and you can cause cracking that you may not see. Best bet is MMA (stick weld) with 7018 rods. Preheat it with a heat gun to a few hundred degrees. Do not, under any circumstances, cool it with anything afterwards.