Thread: EEK Motor Back From Machine Shop To Find This!!

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in a perfect world everything is " prefect " ( HA ) .. iv`e ran plenty of engines for plenty of miles with defects that machine shops wanted to charge me a bunch to fix .. my current 351 in my stang has a cracked main web but works just fine .. put your engine together and run the crap out of it .. that scratch is less than .001 percent of the sealing area of the cylinder ..

Originally Posted by HOSS429

in a perfect world everything is " prefect " ( HA ) .. iv`e ran plenty of engines for plenty of miles with defects that machine shops wanted to charge me a bunch to fix .. my current 351 in my stang has a cracked main web but works just fine .. put your engine together and run the crap out of it .. that scratch is less than .001 percent of the sealing area of the cylinder ..

Considering the photo investigation confirming that the scratch occurred before the honing, if it were mine I'd do exactly as HOSS429 says, unless the shop owner steps up and offers you some great deal after seeing the pictures. Not sure I'd invest the cost of hauling it over to him, given the distance. Of course it's your engine, and you need to be satisfied with the approach.

Best luck, whichever way you go, and let is know how it turns out for you.

Sorry guys, I disagree.
At the very least I would pull the pistons and inspect the rings and piston lands for damage before I'd even think about putting it together.
Bottom line, something caused this, putting it together without knowing what could be very costly. If you pull it apart and find a bad ring or two, you're only out a few bucks and a little time. On the other hand, you run it with a broken ring and you could be into new pistons and boring it again. If you decided to take the risk knowing the consequences, great that's your choice. However, by what I see in the picture, I wouldn't advise someone to gamble site unseen.

Originally Posted by 36 sedan

Sorry guys, I disagree.
At the very least I would pull the pistons and inspect the rings and piston lands for damage before I'd even think about putting it together.
Bottom line, something caused this, putting it together without knowing what could be very costly. If you pull it apart and find a bad ring or two, you're only out a few bucks and a little time. On the other hand, you run it with a broken ring and you could be into new pistons and boring it again. If you decided to take the risk knowing the consequences, great that's your choice. However, by what I see in the picture, I wouldn't advise someone to gamble site unseen.

The basis for my statement is that the "scratch" was BEFORE honing. That means it cannot be a problem with the rings, it happened sometime during the boring process, or removing the bar, then the cylinder was honed. No skin off my nose either way, but logic says it's not something that happened inserting a piston. Just my $0.02, and your decision.

I hear you Roger, no disrespect was intended.
I could be wrong, but I believe I was the first to notice the honing marks appear to be over the score in his picture. My caveat, without knowing the cause (the picture can be deceiving), if they honed over a score that deep, there may be other issues as the slight marks over the honing tend be an indication of a ring installation problem.
I'll stand by my statement, "At the very least I would pull the pistons and inspect the rings and piston lands for damage before I'd even think about putting it together." Of course, he (OP) should wait to see what the shop owner says on Monday first.

Originally Posted by 36 sedan

I hear you Roger, no disrespect was intended.
I could be wrong, but I believe I was the first to notice the honing marks appear to be over the score in his picture. My caveat, without knowing the cause (the picture can be deceiving), if they honed over a score that deep, there may be other issues as the slight marks over the honing tend be an indication of a ring installation problem.
I'll stand by my statement, "At the very least I would pull the pistons and inspect the rings and piston lands for damage before I'd even think about putting it together." Of course, he (OP) should wait to see what the shop owner says on Monday first.

Nothing wrong with that approach, for sure, especially the part about waiting to see what the shop owner says. Can't hurt to pull the pistons & look, provided you've got a good ring compressor and do it right going back together.

I've been anxiously waiting for tomorrow to call and see what he says about it. I'm just worried about him saying yea we'll fix it then just honing the mark out of it and slapping the piston and rings in and saying its fixed.

Understand your apprehension, but everyone makes mistakes. In my book, it is not the mistake by which you are judged, but how you deal with it. If he agrees to fix it, thats the first step to recovery, after that how he fixes it determines his integrity.
if you're worried about the fix, let him examine it first and agree to the repair, then ask him how exactly he is going to fix it. If he says honing, let him know you are prepared to check for uniformity and allowable tolerances.
And this is where the tricky part comes in, if the tolerances are not specified on your receipt (or contract), you are subject to industry standards for this operation. You'll have to research your state laws for the allowable tolerances allowed. Law is the definitive, meaning you are entitled to be whole according to the law. Law doesn't mean right or wrong, it means law. Whole meaning what you paid for, most cases no more.
If you have doubts about his repair, be prepared to check it. Bring a cheap bore gauge, or at least a properly sized ring and feeler gauges. And, check it before you except it. Make them unwrap it, if he's a legit shop he will understand your concern and cooperate in your satisfaction.

Honing away the marks and slapping it back together might be the exact correct solution.

So long as tolerances are maintained, all is good.

By the time that mark/gouge is honed out, the piston clearance will be too big-

I would like to see the work sheet as to what exactly was done and sizes used-

And balance????Deck height?

It would be possible to maybe just put one piston in that hole at whatever size necessary---

I had tore motor down myself carefully and inspecting everything i then brought him the block/crank/rod&pistons and new pistons and had him assy bottom end just the rotating assy I am on a budget build and didn't have enough to have it balanced :/
Anyway on my receipt these are everything that are marked.

install cam bearings/install exp.plugs/rebore block 4.030/deck block 9.010/ polish crank/recondition rods (new bolts installed)/
R&R pistons/ file fit rings (for kb pistons)/clean motor and parts/ assemble(crank,rods,pistons) 1-set of cam bearings
1-set rod bearings / 1-set main bearings/ 1-assy lube. Total with parts $1338.75

Originally Posted by backyardbuilder

I had tore motor down myself carefully and inspecting everything i then brought him the block/crank/rod&pistons and new pistons and had him assy bottom end just the rotating assy I am on a budget build and didn't have enough to have it balanced :/
Anyway on my receipt these are everything that are marked.

install cam bearings/install exp.plugs/rebore block 4.030/deck block 9.010/ polish crank/recondition rods (new bolts installed)/
R&R pistons/ file fit rings (for kb pistons)/clean motor and parts/ assemble(crank,rods,pistons) 1-set of cam bearings
1-set rod bearings / 1-set main bearings/ 1-assy lube. Total with parts $1338.75

What did the shop owner say this morning? Does he want to see the block?

I'm thinking the worker when first installing the bore machine into cyl it left this mark then he continued to finish the boring to see if it would clean up but then seen it didn't but installed piston& rings anyways.
This would cause a cross hatch marks over it if it was done first.
I tried calling repeatedly this morning from both cell and house phone with no answer so i asked nicely for him to call me back on his answering machine. I also messaged him on facebook under there page.
I called another machine shop and he said it could have been caused by the bar being dragged and said if it's deep enough to catch nail then its an issue and to correctly fix it have it bored next size up to see if that cleans it up.

As I see it now----------he bored/honed the block to size for PISTONS you supplied ---on budget-no balance------so idea of going bigger probably wasn't a thought------That scratch didn't come from boring bar-the boring bar size is set above the block and it machines from there downward-----I've seen scrathes like that caused by the rod bolt side of rod on engine disassembly and they will usually be much deeper than wear marks( as yours is)

Your best budjet fix is to dissemble block and have them (If they have a Sunnen CK10 hone) machine that bore out til it cleans up and then get a single piston that size for the one hole-better deal than sleeve and those pistons are an off the shelf number

I wouldn't blame the shop when you handed them the parts and said "use these".
How was the wear calculated? Since you provided the pistons, you must've measured the bores? Yes/ No?

Since this is a budget job, just keep moving forward, that line won't amount to much, you'll never feel it in the butt dyno!