Re: New pistons (archive)

Matt,
The engine has 165k miles and frank said he has never seen the kind of wear the rod bearing have. They were worn almost to copper backing, 1st layer of babbit (sp) was gone. However, no bad wear in the cylinder to speak of. No ridge at top, none. Not even a carbon build up on block. It still has visable cross hatch from original honing. They are shiny but NO scraping or scaring of cylinder walls. I think most if not all wear is on the piston itself.

All that said, I'm not leaning toward NOT BORING the block. I brought it up on the board becuase someone suggested it to me and I had never heard of the possibility before. I thought you ALWAYS bore block when replacing pistons. Just trying to get others reaction.

I'm going to have to bite the bullet and do it right :)

Al help is appreciated,

Michael

How many miles on the engine? Whether or not the block can be honed without being rebored depends on the amount of wear on the cylinders. If you have a ring ridge that is visible or if you can catch a fingernail on it, forget about it, go oversize. Even if the cylinders look pretty good, there is still a chance that once they are honed they will be too large or have too much taper. Also, honing can affect the dimensions of the cylinder enough so that the ring end gap will be too large. If you've got over 100K miles the chances of being able to get away without boring the block are pretty slim, and if you do go that route, chances are you're going to end up with an expensive motor that you won't be happy with. If the head is already off, I would definitely have someone measure all the cylinders with a bore-micrometer before you fork out the dough for new pistons though.

Good luck,

Matt
Maximillian Importing

Remember me...9grand for a bottom end rebuild? Needless to say I'm still trying to figure out what to do.

Here's a question...IF the cylinders are fine (only piston wear) can(or should) you put in new pistons WITHOUT boring the block. This would save a ton of $$$ because the block can be left in the car. Honing the cylinders can be done in the car, along with changing the bearings, etc...

If the answer is no, please say why. I'm just trying to gather as much info as possible.

Also, as an update...I did talk to Frank Fahey and he can rebuild the bottom end, and reassemble the top end for around 6-7K. Not bad BUT no warranty. He said he has never needed to provide a warranty but it bothers me, especially since I have to ship it across counrty (east coast to west coast & back). I talked to Jim at Metric Mechanics...price is higher but has some warranty, $8,500, also assembled and ready to drop in car.

I am now waiting on a dealer price for a new bottom end. Pray for me :)

Michael

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