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Posted by: tornik550 Sep 14 2010, 09:04 PM

I have a set of KB performance 96mm pistons. I recently disassembled most of my engine. The engine was freshly rebuilt (with about 250 miles) however I was having an issue with cyl 3 so I took the engine out.

About 25 miles prior to removing the engine, I stripped the #4 spark plug hole. I replaced it with with a time-sert. I thought that I had done a good job of removing the metal fragments. Once I got the cylinders off, I realized that I missed several metal fragments.

What can I do to fix the piston? Is there a DIY fix? Yes, there are some minor gouges on the cylinder wall- I am going to get it honed.


Attached image(s)

Posted by: Vacca Rabite Sep 15 2010, 08:06 AM

could you try going in with a dental pick to remove those shards, or are they welded in there now? even if you get the metal out, you are going to want to have the piston checked for roundness and possibly machined and re balanced - which would also mean pulling the other two pistons.

Without having it checked, you could end up re-scoring your cylinder.

if you want to go this route, I have 3 used 96mm KB pistons in my shop. I would be happy to sell you one of them for cheap. You would still have to re-balance the other pistons.



Zach

Posted by: RobW Sep 15 2010, 08:09 AM

Ouch....

Posted by: Vacca Rabite Sep 15 2010, 08:11 AM

Zach

Posted by: DNHunt Sep 15 2010, 08:35 AM

This sure has the feel of a disaster that builds from 1 bad choice to another. I've been there a few times myself, most of us probably have, and the hardest thing to do is stop and say enough, "I'm going to do it right". Check the oil first, hopefully every thing stayed in the cylinder. If the oil has bits in it, I'd tear it down. At the very least I'd replace the piston and re-ring. I think if you weigh the fuched piston you could balance the new one by matching the weight.

Dave

Posted by: charliew Sep 15 2010, 03:56 PM

Only if the new piston is havier than the old one. I would try the dental pick or a hacksaw blade with the sides of the teeth ground off so the blade only cuts on it's front not the sides. You can also make the blade the right width that way.

Posted by: brant Sep 15 2010, 04:46 PM

I think its replacement time
I agree with Dave... I've tried to cut corners in the past and then later ended up tearing everything down to fix it the right way after the shortcut didn't work.....

Posted by: tornik550 Sep 15 2010, 07:24 PM

I went outside and tried to pick the metal bits out. It was somewhat difficult but the metal bits came out and the piston is back to new. As soon as I was done I was standing beside the engine stand and saw that the engine started to lean. I saw the brand new engine stand was starting to break. THE ENGINE FELL OFF THE ENGINE STAND!!! or correctly the engine stand broke and the engine fell. One head stud landed on the ground and the other landed on my knee cap. I am somewhat shocked that my knee cap isn't broke. Everything appears well except one head stud is very bent. So any body know where I can purchase one extended head stud?

Of coarse, I will be going to harbor freight and letting them know about the situation. I just purchased the damn thing less than a week ago. I was so happy that I was able to correct the piston problem only to become extremely pissed a few minutes later. I have a very nice imprint of the end of a head stud on my knee. My knee freakin hurts!!! I Think I need to call my local sleeze ball lawyer (just kidding).

Posted by: ripper911 Sep 15 2010, 07:45 PM

lol, sue Harbor Freight!

Where'd you get the engine stand?

Not that I condone sueing everybody...

Posted by: tornik550 Sep 15 2010, 07:52 PM

I just purchased the damn engine stand at my local harbor freight 5 days ago!!! I'm not the suing type either but I need to get enough money to get a new head stud. Just kidding. It is pretty annoying that because they made a crap product, now I have to spend my hard earned money to buy a new head stud. I realize that it is not much money but it is still annoying.

Posted by: ripper911 Sep 15 2010, 07:57 PM

If the stand failed, talk to the seller.
See if they will fix the situation...

:EDIT: By the way, I thought Harbour Freight only shipped the car.
lol, Yeah, sue them too...

Posted by: WFG Sep 15 2010, 08:01 PM

Harbor Freight has cheep prices because it has cheep tools

Posted by: Dr Evil Sep 15 2010, 08:03 PM

Man, I have used many of their stands without issue. Got a pic?

Posted by: nathansnathan Sep 15 2010, 08:08 PM

I had an engine come down once. It broke the fanhousing only. This was using an empi engine stand



The whole stand fell down with the engine on it - don't get a stand like this. It's not made for a type 4 engine.

Posted by: tornik550 Sep 15 2010, 08:09 PM

I'll take one later tonight. There are three pieces of metal that are bolted together with a single bolt. THe main metal pieces held up fine but the main bolt broke which made all the pieces fall apart. If the bolt didn't break, I think that everything would have been fine.

I have a billion tools from HF and I have been very happy. There have been three tools that I have had issues with- leak down gauge, engine stand and orbital buffer. I had an identical engine stand from HF in the past and never had any issues eventhough I was was quite rough on it. Even after tonight, I still like harbor freight.

Posted by: tornik550 Sep 15 2010, 08:10 PM

I'll take one later tonight. There are three pieces of metal that are bolted together with a single bolt. THe main metal pieces held up fine but the main bolt broke which made all the pieces fall apart. If the bolt didn't break, I think that everything would have been fine.

I have a billion tools from HF and I have been very happy. There have been three tools that I have had issues with- leak down gauge, engine stand and orbital buffer. I had an identical engine stand from HF in the past and never had any issues eventhough I was was quite rough on it. Even after tonight, I still like harbor freight.

Posted by: tornik550 Sep 15 2010, 08:11 PM

opps

Posted by: tornik550 Sep 15 2010, 08:13 PM

So does anybody know a good source for reasonably priced head studs for use on engines with spacers? I purchased my set from somebody on this forum several years ago. The quality seemed to be good. I really don't want to spend $350 on a new set of head studs just because one stud is bent.

Posted by: plays with cars Sep 15 2010, 09:32 PM

Sorry, no help on a head stud, but I will second your sentiment that Harbor Freight's leak down testers suck. I bought one, try to use it once, and took it right back.

Posted by: Krieger Sep 15 2010, 10:59 PM

How about Jake Raby or FAT Performance?

Posted by: Krieger Sep 15 2010, 11:01 PM

Two more maybes: Ottos, High Performance House-Rich Bontempi

Posted by: Vacca Rabite Sep 16 2010, 06:02 AM

If you have a local bug shop, they will have the studs you need.

Go over the engine with a fine toothed comb after you have totally gotten over it falling in the first place. You want to be looking for cracks in your heads, cylinders, and engine case. Needless to say, when you put it back together you are going to want to check compression and leak. But before you put it back together take a solid afternoon and inspect everything. Cracked crank or con rod is also possible depending how it fell. Will probably be fine, but crank failure during operation could grenade the engine.

I have owned three HF engine stands. All three worked exactly as I expected them to, though two of them were used to build a rotesserie and were heavily modified.

Zach

Posted by: draganc Sep 16 2010, 10:00 AM

Great idea! Do you have any pictures?

Dragan

Posted by: tornik550 Sep 16 2010, 08:09 PM

Update-

I searched my old emails and found that I had purchased my head studs about 3 years ago from Richard at European Motorworks. I was able to contact him and he was a huge help. I should also note that I have always been very pleased with the studs that he sells. Since he was so helpful to me I feel like I should post a like to their website

http://www.europeanmotorworks.com/

Also, I inspected my engine stand to see what broke. There is one large bolt at the bottom of the stand that holds all the pieces together. The bolt was the only piece that broke. I was able to get a high quality bolt and reassemble the stand. I also put a few extra bolts in for safety.