Motor rebuild

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Sleeper66
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Motor rebuild

Post by Sleeper66 »

I looking for advice.. I have a 2000 bonneville ssei that has a spun rod . car is in excellent condition. Only 151k miles. Is it worth rebuilding. Rebuild bottom end only or whole motor.. Thanks in advice
maxi426
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Re: Motor rebuild

Post by maxi426 »

You'd really have to take it apart to decide. If the bearing is truly spun, there may be debris imbeded in the piston skirts, and through out the motor. If the bearing is just beat, you may be able to get away with a crank kit and replacing the affected rod. Resist replacing the short block with a n/a one. The compression is higher, and the pistons are weaker.
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Re: Motor rebuild

Post by MattStrike »

The general consensus is that getting a running motor from a salvage yard (with a warranty) is the preferred way, I think locally I have seen them in the $500-$700 range, just pull the old engine and replace.

Rebuilding is going to cost more money. You have to replace the rod if that bearing spun, which means at the very least that cylinder needs to be reamed and honed for the new piston rings. It doesn't make sense to do just one though, and you'll want to get the block cleaned and the oil passages checked, new oil pump, crank has to be ground or replaced, new bearings all around because of that, then there are gaskets, line boring the block, etc... It adds up really fast even when you do all your own labor. Average for a DIY person like me is going to be $1500, you can get by cheaper but you'd be cutting corners which means that the rebuild is not going to last.
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Re: Motor rebuild

Post by 00Beast »

3800's are fickle to rebuild. Some do it and have no problems. Some, no matter how much time they spend checking clearances, having everything cleaned and perfect, spin a bearing after 500 miles. It seems like there was some magic that happened at the factory that didn't quite make it into the rebuild books. So, like said, with the availability of used, running engines at cheap prices, it's not really prudent to rebuild. There's no identifying numbers either, so don't be concerned that you're losing some sort of originality. Only you will know that that block and parts didn't first go into that car.
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Re: Motor rebuild

Post by 2003 SSEi »

00Beast wrote:There's no identifying numbers either, so don't be concerned that you're losing some sort of originality. Only you will know that that block and parts didn't first go into that car.
not exactly true. My Engine and Trans are tagged with the production sequence, that matches the vin

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and the vin

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http://www.pontiacbonnevilleclub.com/fo ... 49373.html
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