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Deck surface accident

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Hey guys as title states when i was taking the edges off on the deck i slipped with the dremal. The scratch is 3mm long and about 1mm deep it goes from the coolants passage out towards the the edge of the deck. It is nowhere near the cylinder do you think this will be a problem? To me it seems that it would not worry it overly just after a second opinion. Obviously its not ideal.

Also there is a water gallery that is close to the cylinder that may have been done on abit on to much of a angle. Now i have measured the "fire ring" in the head gasket and it is 3.1mm wide and from the bore to the closest grind spot is 6.2mm there isnt much i can do about it now but what do you think?

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I'd say you'll be just fine as the mark doesn't get to the outside of the deck. You do need to be incredibly careful when doing this and you really don't need to chamfer as much as it appears you've done. All you need to do is just remove the rough finish which takes a light touch with the dremel or die grinder.

As for the fire ring of the head gasket, I'd be surprised if this presents any issues at all due to location.

Thanx for the reply andre. I will keep this in mind for next time its definitely it is easy to get carried away.

Also andre at what point is it a good idea to change bearings if they have bore gauge marks in them? I have seen this asked before but i have had to measure bearing clearance a fair few times because i was having a few funny things go on with the tunnels and wanted to see the affects on the bearing clearances. The marks that have been left can just be felt with my nail when oiled but not with a finger tip. Would like to stick with the bearings if i can as these are the shells the clearances were set with but if they are going to give problems i will get a new set and go through check clearances again if i have to. Will try get photos when i am back at work

The marks from a bore gauge generally aren't a concern and these can be polished using the paper side (never use the abrasive side!) of some light emery paper and a lubricant. Just a light rub is all that's required to smooth the marks away.

The marks ended up beng to deep to polish out from repetitively measuring the clearances to work out a few things for myself with tunnel shape/size

I did end up putting another set of the same shells in that i had in my tool box and the clearances worked in my favour ever so slightly.

They were bearings from mock up on my old block that didnt work out in the end.

They do have scratching in what appears to just be the very top layer from having a crank rotated on them at some point. Do you think the scratching will course a problem? Or should i just buy another set of mains and go again?

The attached photos are of the worst 2 shells sorry for so many pictures just hard to get good photos

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Those shells all look pretty ugly as they are however I'd be surprised if the majority of that wouldn't dissapear with a light polish using the technique described earlier. If in doubt then a new set of bearings is always the safest option however often these sort of marks are more cosmetic than anything.

Hi,

I don't mean to jump your post Jesse, but what are the benefits of chamfering the edges of the block?

Is this done around the coolant/oil passages and the outside of the block face ?

Yes maybe not as far as i went but just to take the sharp edges off from the machine work and remove the potential for a crack to start as there is no longer a sharp edge for the crack to start at. Andre covers this in the engine building course mate

Hi Karim, when the surface of the block is decked by our machinist this results in material around the holes in the deck that can break away and go through the engine. All we're trying to do is remove these sections to aid reliability. It can also help remove stress raisers that can be the source of cracks starting.

Hey andre i went back to my block tonight to start gapping my rings and i have found a little bit of corrosion just starting on the deck surface. The corrosion can not be felt at all with a fingernail or finger tip just seems visual. I have always tryed my best to keep it fairly well oiled as i was always worried about this happening. Is there anything you could recommend to prevent this? I managed to get some photos that it stands out well in. To re deck the block is a 6 hour drive plus a new head gasket. Do you think it will cause a problem?

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Hey andre i went back to my block tonight to start gapping my rings and i have found a little bit of corrosion just starting on the deck surface. The corrosion can not be felt at all with a fingernail or finger tip just seems visual. I have always tryed my best to keep it fairly well oiled as i was always worried about this happening. Is there anything you could recommend to prevent this? I managed to get some photos that it stands out well in. To re deck the block is a 6 hour round drive plus a new head gasket. Do you think it will cause a problem?

Attached Files