Heard a story of a newly rebuilt and never run 348 for an attractive price. Woman's boyfriend bailed out and left stuff behind.I checked it out,took a chance and bought it. Pulled the heads and pan and yup it was rebuilt and never run.Looks real nice,forged pistons,standard crank that mikes good,all new bearings.clean block,pistons are .060 oversize,looks like it was done about 10 years ago. But...there's always a but on these deals.One cylinder has a rust pit about 1-1/2 inches down from the top of the ring travel. The pit is roughly 7/16 inch in diameter.I slid a piston ring down the cylinder a bit to measure the depth of the pit.At most it's .002.Shining a strong light up from below you can see the very slight gap. I ran a bore gauge in all cylinders and they are true with a good looking hone pattern.Other than this one pit all the cylinders look great.I suspect the guy had the engine bored to these pistons and the one cylinder didn't clean up ..................... So.....I had the local machine shop manager look at this...He said just run it ,it'll be ok for typical street use.A mechanic friend said the same. Another guy said to have a cylinder sleeved....probably a tricky expensive job on a goofy 348-409 block. Does any one here have any actual experience with a situation like this?
I had a similar experience with a FE block that was prepped years earlier. I showed up to buy the thing and a mouse had made a nest in one of the cylinders. The mouse piss had severely rusted the cylinder. I had it sleeved for piece of mind. Its still in my truck and doing well. The cost wasn't too bad if memory serves me right. Around $150
You probably would be fine and there are a lot of engines running around in old cars that have similar pits if you really knew the truth. I would freshen it up with new gaskets and try it. If it doesn't work out sleeving isn't all that terrible costwise. You won't do any more damage to the motor by trying except the cost of the gasket set. Don
Have the cylinder measured up accurately, it's quite possible that it might be able to be honed out, or at least most of it. Did the shop offer that option? If not, I agree with most here, run it as is. bob
Very few 348 blocks will take an overbore of more than .060, but sonic testing will tell the tale. On an ordinary street engine you may be fine, but if it was me this would worry me. A sleeve would be tough to fit to a W motor. The combustion chamber design doesn't really lend itself to the process, or allow for a sleeve to be retained properly. Some of the later truck blocks can go to .125 over, but not many of those are around.
The forged piston fit is at the limit right now.Trying to take a few more thousands will make a very loose piston,maybe worse of a problem than the rust mark. reading the comments here and from the machine shop, I'm leaning towards running the engine as is.Then for Ill know for sure,good or bad.
I used to know a self taught mechanical genius who built many amazing things. A**** them were 22 tractors he built during WW2 when tractors were impossible to get. He would start with an old car or truck and modify it. One of them was an International truck he found with the head off and the engine apart, sitting outdoors. The cylinders were pitted with rust but he honed it and put it together with new rings, he didn't have much choice as parts were hard to get too. Boring was out of the question. He said it burned a little oil when he first started it but after 20 or 30 hours of use it settled down and ran great. A few years later he had it apart for a valve job. He said the cylinders were polished smooth but the rust pits were still visible, filled level with hard black carbon. As long as the pitted area is not large enough to snag the ring it should be fine.
348 and 409 engines get sleeved all the time. As others have said, it's not that big of a deal--don't worry about it. More importantly, if I'm reading it correctly, the area is 1.5 inches BELOW thering's travel? Are any rings getting to it at all? Either way, don't worry about it. -Brad
One more vote to run it. I've seen them like that before and they go forever with no hit of oil consumption.
Run it When I was in college a friend had a 289 studebaker and no money. the piston pin keeper same out and put 2- 3 inch long groves about .100 deep in the wall. he replaced the keeper and put it back together. To my suprise It ran fine and would use a quart of oil about every 800 miles.
One more vote to run it. I've seen them like that before and they go forever with no hit of oil consumption. Agreed. I,ve got one running like that now with multiple pits around 3/16" in diameter within 1" from the top with no problems.
Trucked up it is going to weep a bit but it'll probably run. You shouldn't notice any real bad oil consumption. Ther is something that you need to do before you re***emble. Take a scotch brite rag to it and knock the ruff out of it.The scotch brite won't hurt your cylinder any but if you leave the edges of the pit rough it is going to chew your rings as they p*** over it. I have a weak cylinder in my small block. It got pretty wet on break in (long story) and makes about 3 psi less then the other cylinders. It still makes over 400 HP and has for about 130K. The key is to not trash your rings.
Ok,I scrubbed the rust spot And the piston is back in and the heads are in place. Now, I see nothing so all is wonderful.
Always remember this one thing. Denial is a river in Egypt. So now that you got it back together that thing will never run, can I have it.? Oh come on can I can I?
Well you're too far off or I would find you one here. I never was a big W motor guy but a couple of the fellas in the old club always had them and swore by them. They are stump pullers for damned sure.
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