Guest ssherrick Posted January 5, 2017 Share Posted January 5, 2017 The first of many questions - I am new to the forum and also new to vintage car ownership. I recently retired and soon after bought a 1939 Model 41. The car is cosmetically in relatively decent condition and prior to last week, it started and ran well even though I have only driven it at most, five miles at a time. On my way home from getting brakes worked on, the car stalled and died after driving about half a mile. I was able to get off the road and the engine restarted without issue. It stalled and died again when I put the clutch in to go to third gear. I had AAA come to haul me home. I was able to start it again and pulled it into it's bay in the garage. I started to see if I could find anything obvious today and first checked spark. Spark appeared weak from the coil wire. Before I went uptown to NAPA for a new coil, I decided to check the plugs also. When I took off the spark plug cover, I saw that first of all, the plugs that were installed were AC R46SZ and the one in the #7 cylinder had an antifouling extension on it. I pulled several plugs and they were all wet with oil, but the engine runs without missing. I don't know a lot of the history on this car, the man who had it for 20 plus years passed away. The head gasket appears to be relatively new, so it looks as if the head has been off within the last few years. Would like to get some ideas on the stalling and on the oily plugs. Thanks. Stephan Sherrick Cadiz, KY Link to comment Share on other sites More sharing options...
unimogjohn Posted January 5, 2017 Share Posted January 5, 2017 Stephen, are you sure that the plugs were fouled with oil? The engine will not start or run at all with oil on the plugs. Does the engine smoke on start-up? Color? I would run a compression test and see what the values are. Let us know what you get for readings. A compression gauge is only a few bucks and a good tool to have around the shop. But it sounds to me that the plugs are fouled with gas. I bet that the carb needs a rebuild and the fuel system serviced. You could have a load of bad/old gas that will have to be removed. I can usually tell bad gas by smell. If it smells like old paint thinner, it is bad. Keep us posted. Link to comment Share on other sites More sharing options...
Larry Schramm Posted January 5, 2017 Share Posted January 5, 2017 (edited) Stephan, If you can post some pictures of the spark plugs along with the "antifouling extension" we would be able to better help you diagnose your car. Pictures of the engine areas that you talk about are also helpful. Also, have you done a compression test? That would tell you a lot about the condition of the engine. (added) When you do the compression test, be sure to post the numbers for each cylinder here along with the values before you add oil to the cylinders and after. Also we all like to see pictures of new acquisitions by forum members. Edited January 5, 2017 by Larry Schramm (see edit history) 1 Link to comment Share on other sites More sharing options...
Ben Bruce aka First Born Posted January 5, 2017 Share Posted January 5, 2017 And where are you located? Perhaps an old Buick person lives close by. Ben Link to comment Share on other sites More sharing options...
LAS VEGAS DAVE Posted January 5, 2017 Share Posted January 5, 2017 A compression test is the first thing you should do before buying anything. The compression test will tell the condition of the combustion chambers of the motor. It will tell if it has bad or good rings and valves. It will tell you if it is impossible or possible to ever get the engine to run good with the addition of proper fuel mix and ignition. Sometime poor compression or uneven compression can be cured easily and sometimes it requires major work. The compression has to be at least decent if the motor is to ever run good. Link to comment Share on other sites More sharing options...
Guest ssherrick Posted January 5, 2017 Share Posted January 5, 2017 Thanks for the quick replies. I will be getting a compression gauge this week when I get back to town. After sitting for a day, it appears that what looked like oil on all the plugs is now only strongly evident on #7 which is the cylinder with the antifouling extension. The other plugs look pretty clean - I think I may have been seeing carbon deposit dissolved in gas. I have attached pictures of plug #7 (oil) and plug #6 (clean). What is very noticeable today are the oil pools outside the plug holes. This is along the majority of the head, more apparent to the rear. I really appreciate any help that you have given me - hopefully I won't wear out my welcome with my questions going forward. I am in the far western part of Kentucky near the Land Between the Lakes. I do hope to do as much of the work myself on the Buick - at this point in my life I have more available time than ever before. Link to comment Share on other sites More sharing options...
Ben Bruce aka First Born Posted January 5, 2017 Share Posted January 5, 2017 (edited) That oil on the outside is easy to get rid of. There is a bolt holding the rocker arm bracket down directly above each plug. It is a thru hole, open to the plug area. The oil is migrating down the threads. I would pull one bolt at a time and dab some gasket sealer on the threads and re-install. That should take care of the problem. I would remove the anti fouling thingy and run without for awhile. In the distant past, we did an anti-fouling on the other end of the plug. We simply used something, do not remember what, to hold the plug wire a short distance from the plug so the spark had to jump the gap. Did it work?? Man, I don't know, but we thought it did! If the plug fouls, due to excess oil, try a hotter plug. Or remove it and clean frequently. Would imagine the stalling is fuel related. As in not enough. Many reasons for that . Simplest is a plugged gas filter. If it is a replaceable on, do so. If there is a round, about 2", flat, about 1/2" filter just at the carb, it can be cleaned. Some actually come apart. This filter has a filtering medium that looks like tiny brass balls all stuck together. Just blowing air reversed through it will help. I clean mine by soaking in acetone. Just don't grab your wife's nail polish remover! Go buy your own. It is available in quart cans at any hardware/big box store. The fuel pump may also be bad. I would try the filter first. There may be, depending on which arb you have, a small screen in the inlet to the carb that needs cleaning. You can not ask too many questions. And you will get answers. Hopefully some of them will be correct. BEAUTIFUL car. Ben Edited January 5, 2017 by First Born (see edit history) 4 Link to comment Share on other sites More sharing options...
Larry Schramm Posted January 6, 2017 Share Posted January 6, 2017 I would agree on getting rid of that anti-fouling thing. IMO it is nothing more than a snake oil fix which does not fix anything. The old school TEMPORARY fix for a cylinder that is fouling the spark plug because of oil is to put in a hotter heat range plug. In the old numbering system of AC Spark plug if you used a 45 spark plug normally and you had a cylinder that had a problem you would go up to maybe a 46 or maybe 47. They run hotter and would burn off the extra oil. This could also be used for an aging engine that was using oil and just go up one more heat range for all the plugs. Not a permanent fix. It is just a temporary fix. 1 Link to comment Share on other sites More sharing options...
LAS VEGAS DAVE Posted January 6, 2017 Share Posted January 6, 2017 Ben, do you mean that the rocker arm supports have a a thru bolt that leads into the combustion chamber or am I misunderstanding something. Dave Link to comment Share on other sites More sharing options...
Ben Bruce aka First Born Posted January 6, 2017 Share Posted January 6, 2017 6 hours ago, LAS VEGAS DAVE said: Ben, do you mean that the rocker arm supports have a a thru bolt that leads into the combustion chamber or am I misunderstanding something. Dave No, no, Dave. The bolt hole opens thru to just above the porcelain part of the plug. Several "thru" bolt holes in the head, by the way. Ben Link to comment Share on other sites More sharing options...
Brian_Heil Posted January 6, 2017 Share Posted January 6, 2017 And, you have only done a few short trips. This too can cause the plugs to load up. Do the tune-up items, clean the plugs and go for a good 45 minute ride and then inspect the plugs. 3 Link to comment Share on other sites More sharing options...
FLYER15015 Posted January 6, 2017 Share Posted January 6, 2017 I'm with Brian on this approach. Points, plugs, dist. cap are all available @ NAPA. The carb, you can adjust with the mixture screws @ the base, and the float you can check @ the brass plug. Once you have verified that all is close to what the book says, then take her on a good long drive and re-inspect these items. PS; You can still buy AC-49C plugs at most auto stores. A pretty warm AC plug, made for generator applications. They run great in my "40 LTD, which has a bit of a blowby issue, and rarely leaves town. Mike in Colorado 1 Link to comment Share on other sites More sharing options...
Guest ssherrick Posted January 6, 2017 Share Posted January 6, 2017 Thanks for all the great advice. I bought a compression tester today but will wait a few days before testing since it is 18 degrees out today and the Buick is in an unheated garage. It is supposed to get back to the 50's in a couple of days and I will do the checks and tune up then. What spark gap do you use on the AC 49C? One thing I noticed on my current plugs is that they are gapped too wide. If I have trouble finding the AC49C, what other plugs are good substitutes? Link to comment Share on other sites More sharing options...
FLYER15015 Posted January 6, 2017 Share Posted January 6, 2017 I run the AC-C49 copper plugs I found on e-bay a while ago @ a loose .015". If you google this plug, you will see 50 equivalent numbers, however DO NOT BUY ON LINE, till you are sure about the dimensions of the matching plug. Go to an Autozone or Carquest first and check threads, reach, and length of the insulator. This is very important if you want to run a spark plug cover...... On another note, you could pull all the plugs and spray Brake Cleaner all down the length of the head, and clean out all the galleys where the plugs screw in, and the spaces in between. Then when you start her up, you will see where the oil first appears. Then you will know where to start sealing her up....... Ask me how I know to do this............ Mike in Colorado Link to comment Share on other sites More sharing options...
Ben Bruce aka First Born Posted January 6, 2017 Share Posted January 6, 2017 ss, you want to get the engine up to normal operating temp to do the compression check. Ben 1 Link to comment Share on other sites More sharing options...
LAS VEGAS DAVE Posted January 6, 2017 Share Posted January 6, 2017 10 hours ago, First Born said: No, no, Dave. The bolt hole opens thru to just above the porcelain part of the plug. Several "thru" bolt holes in the head, by the way. Ben Thanks for that info Ben. I never knew about that and the FIX is a good idea. Link to comment Share on other sites More sharing options...
Pete Phillips Posted January 7, 2017 Share Posted January 7, 2017 A-C 45 or A-C R45 also works as a good spark plug for that 248 engine. Pete Phillips Leonard, TX Link to comment Share on other sites More sharing options...
FLYER15015 Posted January 7, 2017 Share Posted January 7, 2017 50 minutes ago, Pete Phillips said: A-C 45 or A-C R45 also works as a good spark plug for that 248 engine. Pete Phillips Leonard, TX Pete, 45's may be a bit too cold for ss's application, seeing as how he has a couple of oily plugs in the mix. My '40 came to me with 46's, and after having to clean them every trip, I learned here on the forums that with AC's, the higher # = hotter plug. And since the 49's are still in production, and have a short insulator, I can run them under the plug cover, and don't have to be cleaned as often. Mike in Colorado where it is now -12F Link to comment Share on other sites More sharing options...
Guest ssherrick Posted January 19, 2017 Share Posted January 19, 2017 I finally got to check the compression today. Prior to doing this, I regapped and cleaned all the plugs. They were all at .060 so I brought them down to .030. I let the engine run for about 15 minutes at a quarter throttle to bring it up to operating temperature. It ran a bit rough for about a minute then smoothed out. None of the plugs had oil on them when I pulled them for the test. Following are the compression results: 1 - 65 psi 2 - 70 psi 3 - 70 psi 4 - 70 psi 5 - 60 psi 6 - 70 psi 7 - 70 psi 8 - 65 psi I didn't do any oil in the cylinder nor a leak down test. I think I may want to go to a non resister plug. Has anyone tried Champion J 18 Y? That is the plug my local NAPA says is equivalent to AC 46. They have the Champions available. Link to comment Share on other sites More sharing options...
26-25Buick Posted January 19, 2017 Share Posted January 19, 2017 (edited) For people who may not have seen a set of leak down results I just did a leak down test on the 6 cyclinder in my 26 Tourer (207 cu in straight 6) as I wasn't too sure that the compression test results that I got were accurate as they all around the 45 psi mark, even but well short of the 60+psi they should be. I haven't tried adding oil to see if that improves the situation yet. This engine has 79000 miles but not sure about the age of the rings as the story seems to change depending who remembers what but they will have been in the car at the very least, 40 years. I mention this because all the air in the leak down test seems to be escaping pass the rings as you can hear it whistling in the oil filler pipe. These are all lose numbers #1 35% #2 30% #3 32% #4 32% #5 35% #6 34% I'm facing a similar problem of fouling plugs too. We typical never have temps below 60F and the car has just run about 200 miles. What do you think? Edited January 19, 2017 by 26-25Buick (see edit history) Link to comment Share on other sites More sharing options...
Larry Schramm Posted January 20, 2017 Share Posted January 20, 2017 On 1/19/2017 at 4:34 AM, 26-25Buick said: For people who may not have seen a set of leak down results I just did a leak down test on the 6 cyclinder in my 26 Tourer (207 cu in straight 6) as I wasn't too sure that the compression test results that I got were accurate as they all around the 45 psi mark, even but well short of the 60+psi they should be. I haven't tried adding oil to see if that improves the situation yet. This engine has 79000 miles but not sure about the age of the rings as the story seems to change depending who remembers what but they will have been in the car at the very least, 40 years. I mention this because all the air in the leak down test seems to be escaping pass the rings as you can hear it whistling in the oil filler pipe. These are all lose numbers #1 35% #2 30% #3 32% #4 32% #5 35% #6 34% I'm facing a similar problem of fouling plugs too. We typical never have temps below 60F and the car has just run about 200 miles. What do you think? IMO, looks like you need an overhaul. 1 Link to comment Share on other sites More sharing options...
FLYER15015 Posted January 28, 2017 Share Posted January 28, 2017 26-25, I see a set of AC C49's in your future, mate................. Mike in Colorado Link to comment Share on other sites More sharing options...
26-25Buick Posted January 28, 2017 Share Posted January 28, 2017 Interesting you bring this up Mike. In the last year or so I've changed from the original Edison 37T to Autolite 3076 plugs. I also managed to fail a brand new condenser in my distributor. Although I cleaned the plugs when the condenser failed they have carboned over again. Is the C49 a hotter plug and suitable for the Std 6? Link to comment Share on other sites More sharing options...
FLYER15015 Posted January 28, 2017 Share Posted January 28, 2017 Neil, Now you have to remember, my Buick is a '40 LTD with the 320 strt 8. I learned about the AC C49 plug from the Chevy guys that were having some oil fouling due to rings or valve guides, and did not want to tear their motors down quiet yet. So they threw in a hotter plug. With AC's, the higher the number, the hotter the plug. Since your Buick is quite a bit older than mine, be sure and check for the proper thread size and reach (depth), insulator length too if you are running a plug cover. If you cannot find the C49's at the parts store, they are all over the web, AS IS a conversion chart for NGK or other brands that are made for "down under". Q= why does an Englishman drink warm beer ? He has a Lucas refrigerator......... Mike in Colorado Link to comment Share on other sites More sharing options...
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