Well, I tried my best to figure this one out on my own but with no luck I turn to the experts of the HAMB. The original flathead is smoking so bad from the breather tube that it is constantly filling up the car with smoke and is burning oil at a rate faster than I care to continue with. Exactly 1 qt every 40-50 miles to be exact. Im sure the motor is wore out but I am really trying to get a summer out of this motor before swapping it out. I’ve ran seafoam in the oil and in the fuel with no luck. This last week I let the cylinders soak in some seafoam and that brought my compression numbers up to what I consider acceptable for an 82 year old motor, see below. Anyways, last night I changed the oil and filled it up full with some 20w50 and it seems like it is smoking even more now than before the seafoam. I am at a loss, and after reading all of the threads on this I wanted to get opinions on my specific situation.
Have you ever had the heads off of it? Did the engine sit for a very long period of time? Rings stuck? How bad a ridge ring do you have at the top of the cylinder? Need more information than just a compression test.
Without pulling the heads and looking at the cylinders for wear or a ridge, valve guides, and just the general condition, everyone is just spitballing on what is wrong with your flathead.
I'd put straight 50 in it, put one of those damn paper masks they made us were over the last 2 years over the tail pipe (s). If nothing more it will bring joy to others. Then tear it down and rebuild it next fall.
If you pour oil in the cylinder and the compression raises then your rings are toast. Thats it. It's over. Ive been there. The most you'll get away with is ball honing and re ringing it. I did that last year after I destroyed a piston at the vintage drags. It'll work well to get you buy. Nothing else will work. Seriously.
Stop messing with it. You said that you soaked the cylinders, so did you pull the heads to see what you got going on. Look at the pistons and rings. Look at the ridges. Look at the valves. Look in the valley. If this doesn't help then pull the oil pan to look at it and the internals. Check the road draft tube. Smoke from the exhaust or just the road draft tube? What do your spark plugs say? Run a heavy oil. A flathead is worth rebuilding if you have the money. About $2500 - $5000 depending on what you want to do. Stop using seafoam!
Try RESTORE most Wally World stores or parts houses carry it. It won't cure your problem on a worn out engine but you may be able to get a few more miles out of it . Get the large size can.
Yea, basically there's no mechanic-in-a-bottle that will help much at this point. If the rings are toast, it's likely all other wear clearances are toasty also. Change your plans to switch engines to this year. (You may have a rebuildable flathead, for whatever that's worth.)
I have used a a small amount of BonAmi into each spark plug hole…It can reseat the rings good enough for a few thousand miles… Yeah, using too much is bad…Or pull the heads, scuff the cylinder wall with 180-220 grit paper… this also worke out for the short term..
Compression test don’t make me think of a worn out, dead engine. Is there a vacuum source hooked up some where it shouldn’t be? or maybe running real rich diluting the oil?
I agree ^^^^ those compression numbers aren't great, but not terrible either. Could the breather be plugged up in the oil pan?
So, I actually found and fixed both these issues and it brought the smoke level down enough for me to consider dealing with it for the time being. Thanks for the suggestions
Well, the smoke got a little better but it is still there as well as the oil consumption. I plan to pull the intake and then probably the drivers side head. I plan to check for the obvious, bad gaskets and such, but is there anything else I need to check specifically under the intake? In my opinion there has got to be a very direct source of oil making it into the cylinders to burn a qt every 50 miles and I don’t believe it to be the rings of compression is 90+.
I have read the entire thread and would quote the late W C Fields when he said, "there comes a time my dear Blubber, when we must grab the bull by the tail and face the situation ! ". Your motor had played out its life and is basically dead. Buying additives and such is like buying a saddle for a dead horse. The horse looks nice, but it's still dead. You can waste your money and get nowhere, rent it to farmers to drive through their fields to kill bugs, or bite the bullet and pull the motor now and end the misery. I have built hundreds of flatheads through the years and still love them, however I would not keep chasing my tail to avoid/put off the inevitable. The motor is dead! Call a priest and give it the last rites. Rebuild it and give it a whole new life or set in the corner of your garage until you or someone else chose to bring it back from the dead. Don't spend money, hoping for the impossible. You will get nowhere except for emptying your wallet. If you do pull it down, and it uses a 4 ring piston, the chances are great that the 4th ring has prevented enough oil to travel up the bores and the other rings have chattered, overheated, broken and climes allover themselves? If and when you rebuild it, use a 3 ring piston, or don't install the 4th ring. Either way, your flathead will love you for it. Ford hired an Oldsmobile engineer right after the war, to cure oil consumption. His fix was the 4th ring. Modern ring construction and improved wall finish make up for old engineering. Good luck, and enjoy the flathead once it has risen from the dead!
I'd add that if your block is okay, and if you do as much as you can yourself, find a good machine shop, etc., you can get a good running engine for less money than the figures frequently mentioned.
I think it may be valve guides also. Your engine should have "split" or 2 piece guides and a rubber seal which may still be original and rock hard or cracked. You would need to pull the intake and cylinder heads, I believe, to replace the guides.
Throwing this out because I don't know too much about flatheads, but can oil get sucked into the fuel system through the fuel pump?
I’ve seen too much oil added to flathead motors that have the wrong dipstick. It happened to me on a recent purchase . Too much oil would be hit by the crank ans big rod ends , throwing oil up on the cyl walls . Too much for the rings to handle .
If you have "smoke" blowing out the breather you have excessive blow by pure and simple. Road draft tubes were never efficiant but to vent the crankcase at all with one the vehicle has to be moving at enough speed for the air passing the end of the tube to draw air though the engine and vent it. Thing is that back in the day a fresh totally rebuilt flathead was only good for 60/70 K if that before it needed a ring and valve job. In small towns 100K without having a head off often meant that you got a photo in the home town weekly paper with your car for bragging rights because at the time it was a big deal. Most cars never made it to 100K then. Unless the engine is worn excessively you might get by with a ring and valve job and go again for another 40 or so K. I'd do a leak down test and see if I did have excess pressure getting past the rings. Then go from there. I'd agree that old hard valve seals may be a big part of the issue.
I've posted on this subject in another thread but bear with me. A few years ago, I bought a running, driving '46 Merc in Texas that had been in storage since 1960 and hauled it back to Tennessee. Got it off the trailer and the wife wanted to go for a ride. Took it for a 10 minute ride and the right bank was smoking enough to kill all the mosquitos along the way. Came home, ran a compression check and it was way down on one cylinder. Pulled the head and no broken rings, no scratches in the cylinder walls, no nothing that I could see. Pulled the engine, popped the piston out of the low cylinder, quick hone, new set of rings and put it back together. Compression came up, re-installed the engine, fired it up and drove it around the same route as before. Right bank still smoking heavily. Brought it back home and started to pull it again and, while I was at it, I pulled all the new exhaust out to fix some routing issues. The right muffler weighed about 3 pounds more than the left. Near as I can tell, when the seller pulled the car out of storage, he dumped a lot of oil through the plug holes prior to starting it and the oil wound up in the exhaust pipe and muffler. That cylinder must have been just starting up on an exhaust stroke and he filled the cylinder. Put it all back together with a new muffler and it didn't smoke anymore.
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