Did I buy a Bad Engine "PICS" Pistons look BAD!!!

[BOBS90TURBO]

I just bought this engine on ebay for $350 +$150 shipping, It arrived with the exhaust cam gear cracked and bent, So today I pulled the head and found the #1 and #4 pistons to have big nicks/gouges in a few places on top of the pistons. I think the head will be ok with the cam gears off my other engine(needs re-ringed,smoking a little).

Are these pistons bad, should I even bother putting this short block in my car. The guy I bought it from said it ran good, no smoking or burning oil.

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[Old Mitsu Tech]

Those look more like flame cutting and I do think since you already have it down, I would replace those pistons. Dents from valves, I wouldn't, but those......... Yep!! Definitely

 

[BOBS90TURBO]

So these 2 pistons really are screwed up,, I am not wanting to spend any more cash than I have to, Is there any way these dinged pistons will work, what If I dremeld the dings smooth. I do not drive this car very hard, maybe 15psi.. I do not need any more power, If it would just run smooth without smoking, I would be happy...

If you think these pistons will not hold up, then I can allways re-ring the motor I have in there now, although that sounds like a lot of work,,, any more advise

 

[BISHILVR]

You should have done a leak down test before you pulled the head, that would have told you the answer.

 

[groundPork]

So these 2 pistons really are screwed up,, I am not wanting to spend any more cash than I have too, Is there any way these dinged pistons will work, what If I dremeld the dings smooth. I do not drive this car very hard, maybee 15psi.. I do not need any more power, If it would just run smooth without smoking, I would be happy...

If you think these pistons will not hold up, then I can allways re-ring the motor I have in there now, although that sounds like a lot of work,,, any more advise

I agree. Notice how the dings are pushing the metal of the top edge of the pistons out toward the cylinder walls. This could be scuffing... It was clearly caused by foreign debrit entering the chamber. I am also concerned about the carbon deposits in the chmabers and how they've seemingly been steamed off or flaked off. That chamber is definitely showing oil burning and a lean condition. Also you must concicer since you haven't taken the pistons out to check, that anything pressed into the top of a pistons hard enough to ding it like that, may have been enough force to pinch the top ring. may explain a little of the burnt oil. Certaily wouldn't stop oil from entering the chamber eventually causing detonation. If detonation set in , it usually lifts the top ring land because of heat, and bends the scond land down pinching the second ring. The second ring is a oil scraper and if it cannot move freely it cannot follow the cylinder wall, further aggravating the oil consumption issue.

While this sounds all very elaborate and highly probable, it's really all just speculation for now. What is quite clear is that the pistons, and rings need to be replaced, and the cylinders honed at the very leasst to ensure you have a fresh surface to break the rings in on.

I know you want to keep the budge tight, and that's fine. But be smart and take the short block to a machinist to have it thuroughly inspected, cleaned and if necessary re-machined to work correctly. At the bare minimum... get the block inspected to know what's necessary, you can always choosssse the cheap cheesy route from there but at least you'll know whats going on.

 

[BOBS90TURBO]

Thanks for the advise... I had no way to do a compression or leakdown test, the motor is on a pallet/now engine stand.

I will pull the pistons out in the morning,...... I guess I wasted a bunch of money on a used ebay engine.,,

Will I need to buy a set of new OEM pistons, or can I get away with a set of good used stock pistons. I do not need or want to upgrade to 2g or forged pistons, I am hopeing I can just get a set of OEM's and new rings and hone the walls, throw in new berings, put the head back on and be done with it. Can I get away with this.????????

 

[BOBS90TURBO]

Ok, new Bad info, I think this motor had the pistons pulled and was honed and the head was fixed and then passed off to me as a good engine. Looking at the walls, I can see hone marks, the walls are smooth on #1,2,4, but #3 looks bad on one side, it looks like the side of the piston dug into the wall and then was smoothed out a little...WTF....

Is the only way to fix this to oversize the piston, have the block machined +20 over.

The first 2 pics are of the spot on #3 and the other 2 are of the honing swirls(I guess) on 1 & 2.

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[Defiant]

Ouch.
I wonder what went through those cylinders to divot the head and pistons like that.
Pretty nasty-looking hone job.

 

[RoasT BeeF]

Thats the worst hone job I have ever seen. I would'nt be puttin that thing in my car if I was you. Im willing to bet you could pick up a set of OEM pistons for around $200.

 

[DoyoFCT]

well to answer your original question will it work? sure. ive assembled a motor with pistons that had even worse damage. its from pretty severe detonation due to a rich/lean condition. makes it look like the surface of the moon kinda, i acquired a motor that had all 4 pistons with moonlike crators covering the edge of the pistons. I took a stone to the sharp edges, and cleaned everything very good. re-assembled the motor with a cheapo 30 dollar gasket and it had 144-148 compression across all 4. I later tore this same motor down and re-built it just because I wasn't comfortable putting any power to it. But if you just need something to get you by, it will work unless the rings are bad but its a risk you'll have to take if you "just wana get by"

 

[groundPork]

Thats the worst hone job I have ever seen. I would'nt be puttin that thing in my car if I was you. Im willing to bet you could pick up a set of OEM pistons for around $200.

HEHE... now all we need is some BBQ Chicken!!!!

 

[groundPork]

That thing was definitely run lean. What's weird is you can see where the pistons were pulled from the bores, cause whatever scratched the bore came up above the fire ring, and yes that is the shi**y Shi* lookin hone job. May or may not clean up with just honing. Scuffing looks pretty bad, also... And this a total speculation.... Is the scuffing like that on all cylinders or just acouple? It may have been caused by a broken ring land and or ring caused by detonation. If that were the case, the bearings might be sh**ty as well. I would seriously take the shorty to a machinist.

That being said, you might be able to order .25mm oversize OEM pistons and bore the block... or try the hone and stock bore new pistons and rings, and see what happens next, I just see too many red flags here..

 

[BOBS90TURBO]

I WILL NEVER BUY A USED ITEM ON EBAY AGAIN,,,,This sucks so bad....

 

[BOBS90TURBO]

That thing was definitely run lean. What's weird is you can see where the pistons were pulled from the bores, cause whatever scratched the bore came up above the fire ring, and yes that is the shi**y Shi* lookin hone job. May or may not clean up with just honing. Scuffing looks pretty bad, also... And this a total speculation.... Is the scuffing like that on all cylinders or just acouple? It may have been caused by a broken ring land and or ring caused by detonation. If that were the case, the bearings might be sh**ty as well. I would seriously take the shorty to a machinist.

That being said, you might be able to order .25mm oversize OEM pistons and bore the block... or try the hone and stock bore new pistons and rings, and see what happens next, I just see too many red flags here..

Just the #3 cylinder wall in one spot is not smooth, it is really lumpy feeling with tiny grooves along the wall for about 2" inches, the rest of the piston walls feel perfect.The guy I bought it from said it had good compression and did not smoke, I want to put it back together and test it just to see if he is lieing, I just don't see how that #3 piston could hold compression with the walls like that.

I guess this engine is so screwed, I am not going to mess with it, I am just going to try to re-ring the one that in my car now.

 

[groundPork]

Ok, so you have an extra block, great!. I would love nothing other than for you to be able to get your money back so se what can be done about that. Keep in mind, if the block you bought is of standard bore size, it might be a good potential race motor platform. But you need to have it professionally inspected. That includes everything from the bores, to the MAg test, beaaring bores, everything....If you do get your money back, then good for you! Remeber to test before you tear down.

 

[this_tsi_8urV8]

Since you have the engine out, tell me where on the block is the block ID #...I need to order parts for my 6bolt and stupid dlrs. cant w/o the block ID #, not even the VIN helps. That favor is greatly appreciated, thanks!

 

[BISHILVR]

I think the ID they want is the 4g63 that is cast into the engine. Some blocks also have the vin number of the car they came from stamped into them below the head, but I cant see why they would want that.

 

[this_tsi_8urV8]

4G63t? Hmm...I thought about that, but I was like nah, cant be that number. So I asked them Where I could find the ID and they said on the side of the engine, and I was like WTF...the engine for sure has 4 sides, so which one? And if they are talking about the 2 smaller sides along the fenders of the car, well one is covered by belts and timing components, so thats a no go. And the other I cant see any stampings. Only stamping I see is the tranny's.

 

[dan ritchie]

I WILL NEVER BUY A USED ITEM ON EBAY AGAIN,,,,This sucks so bad....

Yeah Bob, it does suck when someone sells you a junk motor. I even paid you twice what you paid that guy. Sounds like Karma came back to get you. So any plans on reconciling with me for the trash you shipped? Sorry to call you out like this, but when you won't return calls or emails what's a guy supposed to do?

As for fixing your motor, I'd probably replace the pistons (gussing there will be hairline cracks you can't see from the damage), and you might have to bore to hone the walls...your local shop can tell you all the details. If you're really wanting to get serious, you could replace the bearings and do any necessary reconditioning work...might end up being a full rebuild. As much as I find redemption in you getting screwed, I'm still out cash, and expecting some type of refund.

 

[coltboostin]

Looks like a detonation issue.


Either way-I would advise you not run those pistons.