Today was supposed to be a good day, but turned out horrible. I just got all my rotating assembly back from balancing and was going to start the assembly. I finished measuring the main bearing clearance and was getting ready to start on the rod bearing clearance when a discovered a nick in the #1 cylinder wall. I wrapped this block up two years ago and shipped it from CA to FL. I am not sure how, when, or where but somehow it was damaged. I am guessing the depth is near .005" and approximately 2.5 mm wide at the widest point. I have quite a bit of money invested in the rods rings, & pistons. I stuck with 2.5L because the block was perfect. However now it is far from perfect. If I had money I know what I would do, but that is also not an option now. What would be the most economical solution to this problem that is not a "band-aide"??? Any suggestions would be appreciated.

Please see pictures below:

 

If it was me...Sunnen makes a tool, that attaches to a drill, that holds the finishing stones and felts; you'll need the paste and work it down flush - you may be able to rent it somewhere or from someone on RL.

I've seen a lot worse run, you just have to be careful removing the ridge, or what looks like one. Is there a ridge or does it just look that way?

 

I'm not sure there is an economical solution without ring/piston changes. If it is really .005" then you can't go the overbore route and use the pistons you have. You could Niikasil the cylinders but then you may have piston/ring issues (not sure of the iron coat stock pistons are compatable). There's just no metal filler solution for Alusil.

While I'm sure this is not the answer you want to hear. I've seen motors with much worse run perfectly for a very long time with no ill efects. Depending on the texture of the edge, you could break a ring on the ridge but the performance loss I suspect will be minimal. Chat with Chris White and see what he thinks. Personally, I'd be pretty pissed off over it and would roll the dice.

 

Just looks like a ridge, all cylinders measured out at 100 mm with no taper. The problem is the "ding" or nick. It looks like a tick from a hard metal object. I never inserted the rods, so I am not sure how it got there.

 

Jeremy:

Thanks for the reply! I was so pissed, I had to lock up my guns for fear of doing something irrational! I sent the pics to Mike Lindsey this morning. He concurs with your first paragraph. I also agree with this approach, however not having a job for the last five months is killing me. Buying new pistons and rings along with a bore/honing job is pretty much out of the question right now. I might have to consider locating a used block in good condition. Although I am sure that is going to be like finding a needle in a hay stack.

 

That will ruin your day!

If it’s a street / mild performance engine I would deburr the ding and go ahead and use it.
If it s ‘high performance’ street engine then it’s a tough call. I would be tempted to either fix it via oversized or sleeved or look for another block.

If it’s a track / race engine - then irregularities are just not acceptable!

My guess is that you will lose sleep over just it just knowing it exists. I think the only way you will be mentally sound is to fix/replace the block.

 

I feel your pain. I had my number 4 piston go out and when I took the motor apart I had some cylinder wall washing, for lack of a better expression. The bore to the first over bore is 100.5 mm. You probably want to get a bore gauge and determine how deep it really is. But if it is only .005" deep then the first over bore should do the trick. Lindsey charges $600 for the first over bore and they are probably competitive with most out there. However, you will have to pay shipping which will probably on the order of $150 each way or $300 total. You will be out about $900.

I just picked up a short block for $1000, they are not as scarce as one would think. I am debating what I am going to do with old block but I am leaning towards getting it bored out and rebuilding it to have one on the "shelf" for the next time.

These are Alusil blocks and there are not that many people who can do the machining on them. The machining is followed by some sort of acid etch to expose the silica. So it is a lot more involved process than most think. Another option is to have Darton sleeves installed. They machine out the cylinders and install steel sleeves which are more durable to than the alusil but it is an expensive option.

 

Chris:

Thanks for the quick reply! I guess I fit into the tough call area, which is bad news for me. Just got the prices from Mike @ LR for Ski and your reccomended slipper skirt coated pistons, rings, & boring/honing, OUCH!!! Nearly a $2K ding, need another drink! I could offset that slightly if I could find a buyer for my top and side coated JE pistons and very expensive factory OEM rings. Most likely going to have to locate a solid used block on my current budget or win the lottery. Thanks again for the advice/suggestions! Sad day indeed!

 

FWIW, I've seen damage that goes the length of the cylinder wall (ie way worse than yours) and the car still ran good, burned usual oil, and had good compression for a long period of time.

 

Not that you asked, but I am not convinced about using JE Pistons with typical dry film lubricant coating in Alusil bores. If you want to use those pistons in that block, perhaps the best solution is to get is Nikasil coated and honed to match your existing pistons. That way, you have nice clean bores you can use with your existing pistons, and you eliminate both the nick and the risks of running JE Pistons in Alusil.

 

I prefer the expansion rates of the Wossners to the JE - different alloy. Wossner also has a special Alusil compatable coating.

anyway - it still sucks about the little ding....

 

yes it does, those are pretty bores. If there is no budget, I still say rent the tool and refinish that cylinder. I think the key will be the first 10 minutes of running and the first 200 miles, do a compression test and see what you have. You can always do it later, with funding. Like Chris said, if this is a street engine.

 

Ski:

I will have to think about this option for quite some time. This engine is going to be pretty maxed out for a 2.5L and I really don't want to pull the engine again anytime soon. I am a little **** and pretty much go by doing it right the first time. However, with money being so tight I have to consider all legitimate alternatives. Even after sleeping on it, I don't feel much better today. I keep thinking that I can go over there to my garage and the ding will be not there, like this was a bad dream. I did quite a bit of calling around and did not have much look on the good condition used block front. All that were available would still require boring/honing. Might as well use mine if that is the case. I don't want to get off on a tangent, but am curious/worried about the low popularity of the JE pistons in an Alusil cylinder. Very surprised LR never mentioned anything about this. Although I did purchase these parts nearly three years ago. Also, I had both the skirts and the crowns specially coated for this application. Thus the reason for having to buy the factory OEM rings. All other aftermarkets had too large of an end gap. I think I dropped $550 just on the rings.

Just in case I decide to go down that road, do you have any suggestions on who might have the honing aperatus for rent? Is there a site to educate myself on this operation? Thanks for the responses!

 

This probably doesn't belong here, but while searching for a place to rent the Sunnen tool, I located a very good article on Alusil and Nikasil products.

http://www.aera.org/ep/downloads/ep4/EP10-2008_18.pdf

This is very good reading for anyone interested in knowing the differences in the between the two and all of their functions and/or properties.

 

Easy choice for me. If you can live with it/sleep at night, then just leave it alone or try what Ski said. If you can't live with it, then just find a used block. You'll find one if you keep looking, at give it some time.