Hello All. I have a 1950 Ford F3 with a 239 V8. it runs hot oil pressure of no more than 10 lbs, smokes out the breathers and has compression of between 60 and 70 lbs. All of this leads me the conclusion than new piston rings are in order. This is my question. Is it practical or possible to do this without removing the engine? I would like to replace the rings and rod bearings and know that it would be better to remove the engine, but I don't have a lift and would like to leave it in place. Any thoughts, suggestions or advice would be most appreciated. I have never replaced piston rings but consider myself pretty handy.
Here is the main problem with doing an in chassis overhaul is getting the cylinders cleaned up after honing. It can be done but all of the fine metal and stone grit will be everywhere and isn't good to be in there. If you don't get the cylinder walls clean enough for a white paper towel to come out clean when you wipe down a cylinder wall... it isn't clean enough. Just a slight amount of that grit will kill a set of rings in a short amount of time. This is the biggest mistake that most people make when building a motor... not getting it clean!
I certainly would like to avoid a rebuild, but the blowby smoke is driving me crazy. It actually comes into the cabin at stoplights. How much breather smoke is normal for a flathead?
wait until you can do it right. otherwise you are just wasting your time. save up for all the needed parts, and when the time comes rent an engine hoist.
By the time these "Flatties" get to where your's is, it's usually time for a complete O/H. The crank's are usually too worn for new brgs, the bores are usually too worn for new rings (without new pistons), and the cam bearings are also too far gone. We do these for a living and see it all the time, you end up opening the proverbial "can of worms", never fails. Thanks, Gary in N.Y. P.S. Recommend "R&R" and do it right (mentioned above here), this way you won't have to do it over. Good luck, whichever route you choose!
Until you pull the heads, inspect and measure the bore for wear and taper, you really won't know just what you are facing. Also, inspect for cracks around the valve seats. If the engine is a candidate for a ring job, it can be done with engine in place. Garybeard360 is correct about thorough cleaning of the cylinder bores after honing. Wash them with solvent and a bristle brush and, as he says, test with white paper towel for cleanliness. Also watch that the abrasives do not find there way into/around the crank throws. Over the decades, many, many engines have had this, and more, done while remaining in place.
Could be opening a can of worms by pulling it down alright. Those old tired engines are usually worn out all over and it's best to do the job once - properly. If it still runs good you can buy youself a bit of time to save the $ for a full rebuild by hooking up a basic PVC into the intake. That will at least suck up some fumes while sitting at the lights. Run some thicker grade oil and you could get a bit more out of it for a while yet.
To be honest, and I am a flathead fan, if you can't afford to do it right, just pull the engine and tranny and sell it to someone looking for a core. But a newer engine on craigs or ebay or the paper and throw it in there. You will get the power a truck that size needs anyway for pennies on the dollar. The money you won't spend on the flathead will go a lot farther in a newer engine and someone willing to spend the money to do it right will have a good core, maybe. Just my $.02.
None. Some good runners will lose a slight amount of oil either by smoke or leakage. Don't do a half ass rebuild on your engine. Its only a candidate for a complete rebuild. I agree. Buy another or save your nickels and get it done right.
Re; low oil pressure... The main and cam bearings have all been in there as long as the rings,....and would also need replacing. Another factor would be cyl. taper, as well as being "out of round". careful measurements are the way to go, before just doing new rings. I would save up the $$, and pull the engine, have it cleaned and inspected by a reputable machine shop. Happy Roddin' 4TTRUK
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