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Discussion Starter #1
hey guys, i recently did a full rebuild on my 87 Sammy. bored out the cylinders put a bigger cam, etc... we got it together and it ran good and strong for about 2000 miles. (didnt take it over 3000rpms for the first 500+ miles). had a few problems with the timing belt slipping, and ultimately the cam timing gear broke at about 1000 mi. never heard of the happening before. got a new gear it it ran strong again for another almost 1500 mi.

the whole time it had metal shavings in the oil. decent size thin slivers. as i never rebuilt an engine before i though that was normal. my mechanic thought i meant fine metal dust, so he didnt suspect anything. i changed the oil at 100mi, 500 mi, and 1000miles. got to about 2000mis when i checked the oil and it was bone dry. after that it knocked pretty good. i stopped driving it and took the oil pan off and checked the crank/rods.

all the bearings were spun. my mechanic actually moved to Tuscon to work at a performance shop and his boss asked him if we changed the rod bolts, which we never did. we also never filed the piston rings to allow for expansion? i guess we were supposed to make sure there was a .015" gap in the rings. i measured what they are right now and they are around .008" i think, if i remember right. its been about 4 months since ive done anything with it.

so my question is... does anyone know were to get new rod bolts? ARP doesnt make them short enough and all i can find are refurbished rods, and im not convinced the bolts are new. my rods are fine according to the machine shop i took it too before the rebuild.

thanks
 

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I don't think the rod bolts were your problem - it sounds more like you & your "mechanic" didn't know what you were up to - you didn't check the ring gaps, you though metal slivers in the oil were normal, he thought you meant "fine metal dust" - any mechanic worth his salt would have been checking that engine over on the first report of metal shavings in the oil.

As far as I know, most people don't replace the rod bolts on a rebuild (if they did, you would have found them everywhere that sells Suzuki parts), I certainly never have and I'd guess I have around 25,000 miles on the last engine I rebuilt.

Find a mechanic who knows his stuff and have him check that engine over - if all the bearings spun, you probably have a damaged crank, and I would expect the block, main bearing caps & rods to have been damaged also.
 

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Discussion Starter #3
yeah one problem was he moved to the mainland only a few days after completing the rebuild. so he couldnt physically look at it.

ill take the block and crank back to my machine shop and have it checked out. the previous crank was bad cause the #1 rod spun the bearing pretty bad. so i replaced it with a re manufactured crank. the bearings dont look that bad visually. hope it didnt damage anything else...

do you think ring expanding could cause the new bearings to go bad?
 

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Directly, no; indirectly, yes - if the ring gaps are too small, when they expand they can score the cylinder walls and once that metal gets into the oil, it can get into the bearings it will destroy them.

The bearings don't look that bad visually
If the bearings look anything other than perfect - they're unusable, and even if they look perfect, it doesn't mean that they are useable - this is not a business where visual appearance is how it's done, you measure and make decisions based on measurements.

You seem to be saying that this engine has spun a bearing before - there is either something wrong with the engine, or something wrong with how it's being assembled - you need to find an experienced mechanic to look at it.
 

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you know, thats what i thought was happening. the shavings were ferrous as well, so not from the bearings. maybe ill have to have it bored up to the next size then. i just want my sammy back damn it....

thanks for the insight
 

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Discussion Starter #6
the engine was the original with at least 200,000 miles on it possibly 300,000. hard to tell when the odometer only goes to 99,999. it was at 97,xxx in 2005 (18 years old) when i got it. i rolled it over once myself in 6 years. so the chances are that it was at 300,000... so i figured 1 bearing going out wasnt too odd. it it ran out of oil a few times along the way as well. im sure that could be a problem >_<
 

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I'm not certain why you think the shavings being ferrous is of any great significance - they could be from the cylinder liners or from the crank journals - any way you twist & turn it, the engine needs to be disassembled and examined before any decisions can be made on the way forward.
 

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well i was told if the shavings were not ferrous then its a was a good chance that they were from the bearings. i guess that would mean that it would be not as bad as if they were magnetic? considering it could be the things that you mention.

the engine is disassembled, it has been since i realized all the bearings were bad. i took it out to change the bearings when the idea of the rod bolts being bad came up.

but if im not looking for bolts anymore, i can now take it to the machine shop and have him check it all out.

this is all a learning experience for me. i was hoping there would be someone on here that has had a similar problem, and i could get a answer to why something like this would happen. like the cam gear breaking, i know thats not normal by any means
 

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Here's my take on shavings, ferrous or non ferrous in the oil - any time you see shavings of any sort in the oil, you're in BIG trouble, time to tear that engine down & inspect it - and expect bad news - as in replace the engine bad news.

Shavings of any sort means heavy metal to metal contact - ferrous shavings would likely be from the cylinder liners meaning the cylinders are scored, you're looking at least at a rebore, possibly a resleeve or a new block. Non ferrous shavings would come from the bearings or the alloy of the block, if its the bearings you're looking at a damaged crank, which will translate into a regrind or a replacement.
 
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