As many of you know I recently bought this killer 56 Buick, but previous to this car I have only had small block Chevys. This is my first nailhead engine, and yes it leaks here and there and a little everywhere and I do add oil to it, but I want to drive it to back to the 50's car show in a couple of weekends and I have a question for you all. Is there anything in particular with these nailhead engines that I need to know about or any small problems with them that I should look into. Like I said it leaks a little but do I really need to worry about it? Or do you think I'm over reacting and just drive the car and add a little oil? Maybe this question is for the guys out there that have had these Buick nailhead engines.
I too have been playing with sbc's since the 70's. Picked up my first nailhead about 8 years ago and now I'm hooked on them. I have 6 of them now. Rear mails are rope seals and tend to leak over time. They can be replaced with neoprene seals. valley pan leaks can run down the back of the motor and appear to be rear main leaks. valve covers usually are not a problem due to the horizontal sealing surface but an old hard gasket can seep.
I had a '62 401 in my '55 Special. It leaked and I never got around to finding it, so I just checked the oil level more often than I usually would have. I drove it that way to the HRR in BG, about 1800 miles, without a problem. Check the back of the block for leakage from the distributor hole. There's supposed to be an o-ring on the distributor housing just inside the block and if it's nicked, torn, flattened or whatever, it'll leak from there.
If you have an oil pressure gauge and temp gauge that are in working order you have that in your favor. As others have said, depends on where the leaks are. I have driven my 322 on numerous 100+ mile trips. I'm just diligent about checking all fluid levels before and during my travels. When you fuel up, give it a once over. Another thing to inspect would be brake system and wheel bearings. If you break down on the road these parts aren't behind many counters at parts stores. Good luck.
Here is a picture of the nailhead, I looks like valve covers , front timing, and the back of the engine is hard to tell because it's all soaked. When I leave it parked for about a week it leaves about a 6" diameter oil spot on the concrete, transmission a few drops and the rear end is a little wet but nothing on the concrete. Should I be worried about the oil leaks at this point? The oil spot on the ground is where the back of the engine would be.
Pull and mark all your plug wires put a baggie on the dizzy and the carb, get the engine cleaners and the power washer out and hit it from all sides and bottom then you'll see were your leaks are coming from if nothing else it will be clean for your show. Oh the valve cover breathers may need a good cleaning also have fun........................jack
Haha I like it, thanks for the comments guys, I'll power wash and scrub it this weekend and see what I find
Look at the valve covers to see if someone has over-tightened and caused the gasket to slip out. I've seen that happen many times and it causes a leak that runs down the back of the engine onto the floor. Dave.
if your rear end is leaking check that your rear end breather isn't plugged. id give the engine a pressure wash and try to locate the leaks and fix them as road trips can as mentioned be a bad place to look for parts if you break something. seals can start out being a small leak and develop into a disaster quickly so I like to see no leaks. just saying
Drive it plenty as seals might just be dried. They can rejuvenate. Check your levels weekly and do not worry about it for now. Clean everything well so that you can see where the leaks originate. Dusting with baby powder will make it easier. There are antileak additives. They will not hurt anything.
On engines of that age oil use of up to 1 quart in 500 miles is more or less normal. As others have said, check your oil pressure. Is it good? Then your bearings etc. must be OK. No knocks, raps or bangs from the engine? Also good news. Cleaning the engine and checking for oil leaks is also a good idea. Cork gaskets and paper gaskets dry out, get hard and shrink over the years. Brake kleen spray is good for cleaning small areas. Finally take off the oil filler with the engine running and check for blowby. If the engine is good there should be little or no air coming out of the filler pipe. If it is really blowing out the rings are bad. This can build up pressure inside the engine and force oil to leak out. It indicates you should be thinking of a rebuild or overhaul. It doesn't mean the motor is going to blow up or quit, but it does mean it is reaching the end of its life. A worn motor can go on a long time if you baby it and don't beat on it.
They are just like any other engine as far as lieaks ond oil go. As long as you have enough oil in the engine and it isnt putting enough to smoke you out or be a fire hazard on the exhaust I wouldnt worry about driving it. A 6 inch circle is less than a table spoon of oil when poured on concrete and let sit and flow out. Remember that it has a road draft tube at the rear of the engine as well. I would put money on the rear main being the main cause of the leak though. The engine should be a lower compression (obviously 2bbl) 322. I think you might be able to get a thinner shim steel head gasket and a 4bbl intake and pick up about 40-50hp. 1956 had the best heads of all the 322-264 engines. intakes are 322-264 only but valley cover, valve covers, aftermarket distributers will fit all nailheads.
Worked on then as a Buick mechanic in the late 50s. If the rear main leaks it needs new main bearings. They get a bit of ware and the crank beats the rope seal, and they leak. I fixed a lot of them. The bearings can be replaced without removing the crank. We used to get roll out pins from SnapOn. Fit then in the crank oil hole and roll the engine slowly, out they come. Reinstall same way. Seal replacement is a bit different but we got on to a trick and did them quite easly. Iceman
Worn mains could surely cause the leak, but low oil pressure would likely show up as well. Dont forget that now the engine is about 57yrs old and sometimes old shit just leaks. We do a fair amount of service work and have done 3 rear mains this year on older engines. Two were old/hardened rope seals, one was a neoprene 2pc. Not one of the engines needed mains or any other internal work, just seals The dowel pin trick sounds good, I would just be afraid of hitting the machined surface of the block. I find a hard piece of plastic or wood and a small mallet works just as well for loosening up main bearings. The seals can be tricky but usually a smaller piece of plastic or something can help push the old one out far enough to grab it with needle nose pliers. A bit of assembly grease/white lithium based helps on the install.
Nailheads were excellent engines, but as with anything, maintenance is the key to keeping them in good shape. If you don't have time to diagnose and repair the oil leak [often valve cover gaskets] Be sure to check your oil at every fill-up, unless it's leaking severely, then more often. ---John
Could be rear main seal, oil filter adapter, trans leaks, or oil filter gasket itself. Looks like your buick is a 2 door tourback sedan. Similar in color to mine. Gotta love these old buicks, in my mind, they pick up where the 55 chevy left off as far as styling and features. Here is a pic of my 55.
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