Chip/dent in piston what to do?

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Im currently working on a headgasket on a 1fz fe and when i removed the head i found the headgasket was damaged in the 6th cylinder. The edge was bent and the top of the piston was smashing it against the head. Theres no damage on the head but im concerned about the chip or
20210622_183034.jpg



dent in the piston. Any thoughts on what to do now? Can i still use this ? can it be fixed ? What brand should i replace with. I do all 6 im assuming?

20210622_182025.jpg
 
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I wouldn't worry about that based on location.

What do the cylinder walls look like?

Make sure you vacuum out the debris around the top of the piston, as that appears to be abrasives and crud that could scratch the cylinder walls.
 
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I agree, clean it up well and leave it. You won't notice any difference, and rebuilding the bottom end is something you want to avoid unless you really need to. Gets expensive quickly.
 
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Thanks for the replies! So my plan was to leave it alone but looking into another cylinder the wall looked like this and me being me I for sure dug in deeper!
20210625_140151.jpg
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The dent or mark in the piston in on the far left in photo and the far right piston you can see wear marks from something in there. I know the photo of the cylinder wall is pretty bad but thats for the far right cylinder. Other than that I would say the walls look great in the rest.
So i guess now my original question is going to change a little bit. Should i just send the block out to get honed? Now that you say the piston with a chip is okay is the other with wear marks okay? Sorry for the lame questions but never had to dive in this far.
 
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Thanks for the replies! So my plan was to leave it alone but looking into another cylinder the wall looked like this and me being me I for sure dug in deeper!View attachment 2725372View attachment 2725371
The dent or mark in the piston in on the far left in photo and the far right piston you can see wear marks from something in there. I know the photo of the cylinder wall is pretty bad but thats for the far right cylinder. Other than that I would say the walls look great in the rest.
So i guess now my original question is going to change a little bit. Should i just send the block out to get honed? Now that you say the piston with a chip is okay is the other with wear marks okay? Sorry for the lame questions but never had to dive in this far.
If you're just gonna hone it, why not do it at home? 4" ball hone should work fine on the FZ's 3.94" cylinders
 
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So i guess now my original question is going to change a little bit. Should i just send the block out to get honed? Now that you say the piston with a chip is okay is the other with wear marks okay?

The deeper you dig, the more questions there will be.
You've ripped the top off a can of worms.

Everything you take apart is potentially compromised / questionable.

What's your end game?
Do you want a brand new engine, or keeping this one together as long as possible until it truly needs a rebuild?
How much are you able to justify spending on it right now?

Do you go all the way and measure crank journals, linish the crank, replace conrod bolts, deck the block, blah blah blah

The piston looks OK
The cylinder wall looks OK (from a single photo).

These engines aren't made of crystal, they'll run for a long time in less than perfect condition
 
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Im more than willing to to do any of it i can from home i would prefer it. Any recommendations for a good ball hone or will any cheapie the correct size do.
My end game is to have a reliable running engine i know they are well built but at 220k and I just bought this 80 not running taking a gamble. it didnt have a starter and it had water in the oil so i dont really know anything about the health of the engine. I have a full toyota gasket kit for it on hand The head has been surfaced and cleaned ready to go I would love to slap this all backtogether and be done. I dont have the money for a brand new full rebuild but i got what i need to do what really should be. I appreciate the input it make me feel more confident of just using what i have and putting it back in.
 
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Im more than willing to to do any of it i can from home i would prefer it. Any recommendations for a good ball hone or will any cheapie the correct size do.
My end game is to have a reliable running engine i know they are well built but at 220k and I just bought this 80 not running taking a gamble. it didnt have a starter and it had water in the oil so i dont really know anything about the health of the engine. I have a full toyota gasket kit for it on hand The head has been surfaced and cleaned ready to go I would love to slap this all backtogether and be done. I dont have the money for a brand new full rebuild but i got what i need to do what really should be. I appreciate the input it make me feel more confident of just using what i have and putting it back in.
A 4" ball hone is probably the most common size. Honestly you could probably pick one up at your local auto parts store, although you might want to get a higher quality one online.
 
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Ill shop around online for one always seem to find better options.
You also need to look up proper operation instructions for it as well.

There is a "speed" of insertion and retraction to give a proper cross hatch as well as rotation speed. You don't just run a drill wide open and shove it in the hole.

You need to give it a bit of foreplay... ...
 
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Well you're committed now, no turning back. You need to understand, by taking the bottom end apart, it's not as simple as bolting everything back down and calling it done. The tolerances in the bottom end are insane. Nothing goes back together 100% the same as it came out, and a small mistake here is the difference between an engine that runs for another 200,000 without issue, or suffers catastrophic failure after 2,000.

In my opinion, now that you're here, don't take any shortcuts. You need to check everything to make sure it's in spec. Live by the FSM. Follow it to the letter. You'll need some tools you might not have if you haven't done bottom end work before. You'll need a dial gauge which can measure both internally and externally, a good set of precision micrometres, piston ring expanders, a thickness gauge, I'd use some plastigauge too (techniques differ here, but the FSM describes using it, so I'd go with it if you're not experienced enough to vary from the official guide). A good torque wrench you trust to be really accurate. More stuff I'm forgetting I'm sure, check the FSM for tools they reference vs what you have.

In terms of parts, you'll need new bearings and thrust washers. No point trying to reuse them with where you are now, and you need to make sure they're matched to your clearances if there's some wear on the crankshaft. You'll need new pistons, piston rings, oil seals. I'd personally replace all the bolts too just because, but you could probably reuse them.

For your procedure, make sure you 100% don't mix up the order or direction of anything. I personally would have put matchmarks on everything before disassembly. You might want to go back and mark them with something now, to make sure if things get knocked over or mixed up, there's no way you'll ever lose track of order and orientation. You should lubricate everything, especially the working surfaces, so that there's no chance of any rust forming before reassembly. You need to have a very clean work area for the final assembly, as you don't want any grit whatsoever to get onto the working surfaces.

Don't rush. Take your time. You should expect to be working on this for months now. Quadruple check everything and go slow and careful, and you can do this, but this is absolutely the most precise, most important part of the entire vehicle. Treat it with care and respect.
 
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You also need to look up proper operation instructions for it as well.

There is a "speed" of insertion and retraction to give a proper cross hatch as well as rotation speed. You don't just run a drill wide open and shove it in the hole.

You need to give it a bit of foreplay... ...
You forgot to mention the lube! Always use proper lubrication when honing bores, kids!
 
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Maybe I'm a wuss, but I wouldn't attempt to hone the bores yourself unless you've got someone experienced to guide you. If you determine there's actual machining work to be done, take it to a machinist. You can inspect, measure, disassemble, reassemble, but I'd pay a few $$$ to get someone with better gear and more knowledge to do that part. I'd also get the crank shaft inspected and polished by a specialist, regardless of how it looks to the naked eye.

And make sure you use proper assembly lube when you put it all back together.
 
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Maybe I'm a wuss, but I wouldn't attempt to hone the bores yourself unless you've got someone experienced to guide you. If you determine there's actual machining work to be done, take it to a machinist. You can inspect, measure, disassemble, reassemble, but I'd pay a few $$$ to get someone with better gear and more knowledge to do that part. I'd also get the crank shaft inspected and polished by a specialist, regardless of how it looks to the naked eye.

And make sure you use proper assembly lube when you put it all back together.
If there are no visual or tactile indications of damage to the bores, re-honing at home is perfectly acceptable. Same with the crank, check for any signs of damage and if there are none just polish it up (if you want to) and use plati-gauge to get your clearances right.

You can take it to a shop to do this but they are just going to do the exact same thing while making your wallet a bit lighter in the process.
 
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If there are no visual or tactile indications of damage to the bores, re-honing at home is perfectly acceptable. Same with the crank, check for any signs of damage and if there are none just polish it up (if you want to) and use plati-gauge to get your clearances right.

You can take it to a shop to do this but they are just going to do the exact same thing while making your wallet a bit lighter in the process.
Honing the bores can be done at home, but if you've never done a single one before, I wouldn't recommend trying it unassisted for the very first time on an engine block you care about. As for the crank, I personally wouldn't attempt to polish that at home under any circumstances. The kind of gear required to do that properly is beyond the scope of what can be done at home, you're likely to do more harm than good IMO. It cost me about $80 to get the crank inspected and polished by a proper crank specialist when I did a rebuild. Well worth the cash spent in that area. You need that surface to be perfectly smooth and perfectly round. Going at it with a bit of emery paper in the backyard is not a good idea. There are tricks that probably work ok in a pinch, but why cheap out on this one area, when those working surfaces are the most precise and important in the entire engine?
 
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Okay soo... my local machine shop will hone / clean for less than 100 so thats worth it to me instead of buying a hone ill use just the one time. Id love to try it but maybe ill start on a small engine or something. As for putting this back together of course id do it right take my time when i said slap it together i didnt literally mean it. Anyways i guess ive got some decisions on what to do and replace. I never fully removed the crankshaft if thay counts for anything i just sliped the pistons out around it. I do have everything marked and layed out very well (for my standards) i do understand that the crank shaft and everything else will be removed before it gets honed if i go that route. Thanks everyone for keeping this going its very helpful insight for me . If anyone lives in the wenatchee wa area and wants to take a look i got cold beer waiting for you.
 
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Okay soo... my local machine shop will hone / clean for less than 100 so thats worth it to me instead of buying a hone ill use just the one time. Id love to try it but maybe ill start on a small engine or something. As for putting this back together of course id do it right take my time when i said slap it together i didnt literally mean it. Anyways i guess ive got some decisions on what to do and replace. I never fully removed the crankshaft if thay counts for anything i just sliped the pistons out around it. I do have everything marked and layed out very well (for my standards) i do understand that the crank shaft and everything else will be removed before it gets honed if i go that route. Thanks everyone for keeping this going its very helpful insight for me . If anyone lives in the wenatchee wa area and wants to take a look i got cold beer waiting for you.
$100 sounds like a good deal, just make sure they are a reputable shop that knows what they are doing. Try to talk to the person doing the work beforehand if you can. Did they say anything about crank polishing?

If your block doesn't need to be bored over and you're staying with the stock pistons, you could just elect to replace the one damaged one, although as others have mentioned I don't think it would make a noticable difference. It would just be for peace of mind.
 
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slow95z

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Make sure they don't give the block an acid bath to clean it up or you are going to have a bad day.
 
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You'll need new pistons, piston rings, oil seals. I'd personally replace all the bolts too just because, but you could probably reuse them
You won’t necessarily need new pistons...

I have rebuilt a 1FZ before and it was basically strip everything down, hot tank it, had the block decked and honed, fitted new bearings, piston rings (using stock pistons) and a full Toyota gasket kit. Cost me less than $1000 and a couple of weekends, still going strong years later.

while I agree you want to do things right, it’s not a race engine. Tolerances don’t need to be absolutely perfect... In my case the piston ring gaps were probably a little on the large side (with the increased bore size due to hone) which may cost me a few horsepower... but if you just want to drive around it’s perfectly functional. I mean, I had a 12HT diesel that drove for years with multiple broken piston rings and chewed up ring lands, power was down a little and oil consumption was a little higher but not crazy. Thing is, a freshen up on the cheap can still work well for a long period of time.
Only thing I’d recommend is plastigauge on at least one main and rod bearing just to confirm they are the right size. Other than that should be fine...
 

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