schultz23 Posted November 18, 2021 Share Posted November 18, 2021 This car was my dads and I've had it for 7 years doing mostly cosmetic updates and regular maintenance. It has come to the point where I just have to downsize and simplify my life so decided it was time to find a new home for the car. I have showed it to several people with positive results but had a problem crop up while doing a test drive this week. The car starts, stops and turns just fine but it has developed a miss in the engine. I have replaced the rotor, cap, points and wires and awaiting delivery of the new plugs in the next two days. I have adjusted the valves and carb. but the miss persists. I started the car and while running, pulled each plug wire to see which cylinders were affected. Number 2 and 5 made no difference in the RPM so that is where the problem appears to be. Since the the plug holes are 7/8 inch, I had to find and order an adapter for use with my compression tester. That should be here in the next couple days so I can see if there is a ring or valve issue. Are there any other things I should be checking or am I missing something else to try for isolating the problem? It's weird that this just happened when trying to find a new home. Thanks. Dale Link to comment Share on other sites More sharing options...
dibarlaw Posted November 18, 2021 Share Posted November 18, 2021 (edited) Dale: I hope you zero in on the issue. At times the valves can stick on these cage valve Buicks. Particuarly if it has sat for a while. I would remove the side push rod cover and check to see if any of the push rods are bent. The 1922-6 engine. When turning over the engine by the hand crank we could see three of the push rods bending out because of the stuck valves. Also remove the rocker cover to see if all the rockers are rocking for proper valve movement. We straightened bent push rods for a 1922-6 and freed up stuck valves with penetrating oil and tapping with a brass hamer. Make sure all is well oiled afterward. The car looks lovely in more correct colors. Closer to the correct cobalt blue. Most of these 1923-44 that I have seen were repainted bright red or yellow. Edited November 21, 2021 by dibarlaw spelling (see edit history) 1 Link to comment Share on other sites More sharing options...
F&J Posted November 18, 2021 Share Posted November 18, 2021 Don't need to wait for the adapter; I just put a thumb in each hole and have somebody crank it. That's for looking for dead holes, if the "air" won't blow past your thumb when you have a good seal to the hole, then that hole is dead, even if you feel a bit of pressure. I agree to suspect valves, and do all of the suggestions in post #2, but you need to know if those 2 cylinders are dead first. 1 Link to comment Share on other sites More sharing options...
1912Staver Posted November 18, 2021 Share Posted November 18, 2021 It's not just that the valves stick. Sometimes the cages themselves rotate in the head and cut off flow in the port. You need to remove the intake and exhaust manifolds and make sure the cages are still correctly located. Link to comment Share on other sites More sharing options...
schultz23 Posted November 18, 2021 Author Share Posted November 18, 2021 Thank you for the quick responses. I will take a look and see. I did adjust the valve lash last week and they all seemed to be moving properly but will take off the side cover and look at the complete rod. Link to comment Share on other sites More sharing options...
CHuDWah Posted November 18, 2021 Share Posted November 18, 2021 42 minutes ago, schultz23 said: Thank you for the quick responses. I will take a look and see. I did adjust the valve lash last week and they all seemed to be moving properly but will take off the side cover and look at the complete rod. I can't add anything to the above suggestions but I see Kokopelli on the garage wall. His flute music is supposed to be good luck - maybe you haven't been listening closely enough. 😁 1 Link to comment Share on other sites More sharing options...
schultz23 Posted November 19, 2021 Author Share Posted November 19, 2021 I am going to start listening MUCH closer for sure. All the help you can get etc. Link to comment Share on other sites More sharing options...
Larry Schramm Posted November 21, 2021 Share Posted November 21, 2021 Very nice looking car. Maybe the car is telling you not to make a sale and "keep me"? 3 Link to comment Share on other sites More sharing options...
schultz23 Posted November 22, 2021 Author Share Posted November 22, 2021 New news. Got all the stuff to do a compression check and competed that this morning. Cylinders 1,3,4 and 6 all read between 55 and 60. Number 2 reads 30 and number 5 is 40. What is the best way to figure out whether the culprit are valves or rings and what would be your suggestions for proceeding. Thank you again for your help. Dale Link to comment Share on other sites More sharing options...
Tom Devoe Posted November 22, 2021 Share Posted November 22, 2021 2 hours ago, schultz23 said: New news. Got all the stuff to do a compression check and competed that this morning. Cylinders 1,3,4 and 6 all read between 55 and 60. Number 2 reads 30 and number 5 is 40. What is the best way to figure out whether the culprit are valves or rings and what would be your suggestions for proceeding. Thank you again for your help. Dale I need one of these adapters. Can you post what you bought and if it worked as promised? Thanks!! Link to comment Share on other sites More sharing options...
JACK M Posted November 22, 2021 Share Posted November 22, 2021 (edited) Find a leak down tester. Most engine shops should have one. Be sure that all of the spark plugs are removed. The tester will hold a regulated amount of air into a cylinder via the spark plug hole, then you can hear where your leaks are. Some times thru the carburator, sometimes the exhaust, sometimes the next plug hole over. Possibly the oil fill. You might even hear bubbles in the radiator. Edited November 22, 2021 by JACK M (see edit history) 1 Link to comment Share on other sites More sharing options...
schultz23 Posted November 22, 2021 Author Share Posted November 22, 2021 A-6056 Compression Tester Adapter (modelastore.com) Worked perfectly. Link to comment Share on other sites More sharing options...
JACK M Posted November 22, 2021 Share Posted November 22, 2021 But didnt you ask how to figure the culprit? Valves, rings etc. ? The leak down tester will help narrow it down, Only trying to help. Link to comment Share on other sites More sharing options...
1912Staver Posted November 22, 2021 Share Posted November 22, 2021 Did you check if the valve cages have rotated ? It is a very specific to these cars problem that happens to these cars reasonably often. Very few other cars have valve cages. There is nothing to stop them from rotating other than pressure from the retainer nut. Over time the cages can rotate. No tang or anything else to stop movement . Link to comment Share on other sites More sharing options...
wayne sheldon Posted November 23, 2021 Share Posted November 23, 2021 4 hours ago, schultz23 said: A-6056 Compression Tester Adapter (modelastore.com) Worked perfectly. 3 hours ago, JACK M said: But didnt you ask how to figure the culprit? Valves, rings etc. ? Jack M, I think he was answering the other question. Your suggestion is excellent by the way! Another thing. Do your standard compression test cold, like you did. Then, on the cylinders that are low, several squirts of motor oil onto the piston tops. allow a few minutes for the oil to find its way down to the rings. Then do another compression test (still cold). If the problem is worn or stuck rings, the oil will slow the leakage and should raise the compression somewhat on the retest. If the oil doesn't raise the compression for the second test? The problem is most likely the valves. A very good friend has a 1915 big Buick (C55 I think?). And yes he has had to reorient the valve cages a couple times. 2 Link to comment Share on other sites More sharing options...
schultz23 Posted November 23, 2021 Author Share Posted November 23, 2021 Thank you for the suggestions. I will try the compression test cold as well as checking the valve cages and leak down test. Can you give me some detail on the cages i.e., location, adjustment, alignment and how to reorient. Not at all familiar with them. Link to comment Share on other sites More sharing options...
1912Staver Posted November 23, 2021 Share Posted November 23, 2021 (edited) With the cages you can only check by removing the intake and exhaust manifolds. The cages are cylinders that have an opening that normaly is located so it matches the position of the intake or exhaust port . When you are assembling the engine you drop the cage into the recess in the head , rotate it by hand until it lines up with the port and lock it in place with the retainer nut. But other than pressure from the nut there is nothing that mechanicaly locks the cage in that position. Over many running and cooling off cycles the cage can slowly rotate and the port in the cage no longer aligns with the port in the head. Needless to say , very poor running results. More common with the exhaust cages, but it can also happen to the inlet cages. But unfortunately without removing the manifolds you can't see any of this. Not surprising you are not familiar with this problem. Very few cars other than pre 1924 Buicks use valve cages. And those that do usually have a way of making sure the cage can't move over time. Buick was one of the very few that had no mechanical locking in correct position of the cage. Valve cages are common on very large diesel engines right up to today, particularly on exhaust valves. But modern practice always has a way of preventing the cages from moving once the engine is assembled. Usually Diesel cages have bosses at the top that are located by hold down studs. Once they are bolted down there is no chance of movement. Edited November 23, 2021 by 1912Staver (see edit history) Link to comment Share on other sites More sharing options...
schultz23 Posted November 23, 2021 Author Share Posted November 23, 2021 If the cage is no longer aligned with the port, would or could that cause a change in the compression for that cylinder? I assume you have to remove the head to re-align the cage if it has moved and where is the retainer nut located. Just trying to get my head around how it all works. Link to comment Share on other sites More sharing options...
1912Staver Posted November 23, 2021 Share Posted November 23, 2021 If you can remove the head on a Buick cage valve 6 my hat is off to you. Buick used a one piece block head unit on these cars. That's why valve cages were used. The retainer nut is right at the bottom of the valve spring. It is not a hex nut, rather that circle of prongs something like a castle nut. You need a special tool to remove or install the retainer nut. Look closely at the base of the valve spring and you will see what I mean. Sometimes they are very tight and difficult to remove. Best done after a run when the engine is good and hot. The cages themselves can also be quite difficult to remove depending on how much of a carbon build up is present. Do you belong to the cage valve Buick association ? Dean Tryon's group. Tons of technical advice in the newsletters. I strongly recomend you join, all the tech info is available on a cd from Dean. These engines have several unusual features. Link to comment Share on other sites More sharing options...
schultz23 Posted November 23, 2021 Author Share Posted November 23, 2021 Wow. Had no idea. I will look into the group to get a little smarter, hopefully. Do you know if that cage movement would cause the compression issue I'm seeing? Link to comment Share on other sites More sharing options...
wayne sheldon Posted November 23, 2021 Share Posted November 23, 2021 The valve cages have an opening in their side to line up with the intake and exhaust manifolds. This is what has to be aligned with the manifold ports. If the cage rotates, a closed off side of the cage begins to block that port passageway. They can rotate a bit, and not make much difference in the running. However, if they go beyond some point less than halfway, they will begin to restrict the flow of gasses either in or out. If an intake closes down a bit, less air and fuel mix goes into that cylinder than it does in the others. This results in a weak firing and momentary loss of power. If the cage continues to rotate, it can almost completely block off the flow, and a given cylinder will become totally dead power-wise. If an exhaust cage rotates a little bit, again, it may not make a noticeable change in power. However, if it closes off a bit too much? It is a little more difficult to visualize, however, the effect is the same. Fresh fuel/air mixture 'can' be pulled into the cylinder, however the much higher pressure exhaust gasses cannot all get out! Being trapped inside the hot cylinder, when the intake stroke begins, the trapped higher pressure gasses push back on the intake stroke preventing any intake of fresh fuel/air mixture. Again, no fire, no power, and a basically dead cylinder. The lack of burnable mixture results in no fire, which in turn results in no higher pressure to push back, which will then let in a small amount of fresh fuel/air and result in a weak fire. The whole thing struggles for a balance of changing pressures, sometimes resulting in firing back through the carburetor (sometimes they do not do this?), and generally runs a bit rough. I see you posted another question. I was just now debating with myself whether to go into this issue or not? But since you ask. At the lower speeds used for usual compression checks? Valve cage rotation may not show up unless the cage has rotated to almost completely closed. The reasons for this are complicated. However, if a cage is anywhere near completely closed? It can result in a low compression test. For that reason, I personally would more expect the issue to be the rings. However (I do use that word a lot!), checking the cage alignment is fairly easy to do, and since Buicks using valve cages (no removeable head) are known to have issues with cage rotation? I would recommend pulling the manifolds and checking them. If the problem does test out to be rings? Quite often, these old engines will have rings partially stick in the ring grooves of the piston, and therefore not seat properly against the cylinder walls to seal the compression. SOMETIMES (NOT always!) some magic oil MIGHT help free them up. Never really been a fan of that myself, but sometimes it does work. SOMETIMES. simply running the car gently for a couple hundred miles will free up the stuck rings. If an engine sat for a few years, whether just an old engine or one that had been rebuilt somewhat (or even completely rebuilt provided it was run a fair amount before letting it sit too long?), sometimes the rings coupled with a bit of carbon buildup, and oil drying out from petroleum evaporation, the rings will simply get stuck too deep in the grooves. A major rework may not be needed, however, pulling the offending rod and piston might be necessary to clean it up. And if you do pull the piston, you may really need to put new rings in it. Link to comment Share on other sites More sharing options...
schultz23 Posted November 24, 2021 Author Share Posted November 24, 2021 Wayne, Jack, 1912Staver and others, thank you for your suggestions and help. The more I learn about how this engine works, and its uniqueness, the more uncomfortable I get in tackling a fix that I can actually do. As a result, I'm going to try and find someone with the knowledge, tools and ability to take the car and finish what has already been started. The body, paint and upholstery are in excellent restored condition and with the work needed on the engine, should be a very nice completed car. Do any of you know of someone that might be interested? I am located in Litchfield Park Arizona just west of Phoenix. Link to comment Share on other sites More sharing options...
1912Staver Posted November 25, 2021 Share Posted November 25, 2021 They are not a difficult engine to work on. They just have a few unusual design features. The stock Marvel carbs are so so at best , but with carefull attention can be made to run reasonably well. But otherwise once you get used to the things like the cage valves they are just a reasonably basic, later teens 6. Both the rockers , and the roller cam followers can become quite worn. But no more difficult to repair than most teens engines. Join the owners group and get the tech CD. A vast amount of good advice on living with these cars. They were very good sellers in their day. And still a reasonably popular car today. Link to comment Share on other sites More sharing options...
AzBob Posted November 26, 2021 Share Posted November 26, 2021 Probably better results posting on the "Buick Pre War Forum" https://forums.aaca.org/forum/60-buick-pre-war/ Link to comment Share on other sites More sharing options...
Brian_Heil Posted December 13, 2021 Share Posted December 13, 2021 On 11/18/2021 at 12:30 PM, 1912Staver said: It's not just that the valves stick. Sometimes the cages themselves rotate in the head and cut off flow in the port. You need to remove the intake and exhaust manifolds and make sure the cages are still correctly located. Pulling cages is far easier Link to comment Share on other sites More sharing options...
Brian_Heil Posted December 13, 2021 Share Posted December 13, 2021 On 11/22/2021 at 3:35 PM, 1912Staver said: Did you check if the valve cages have rotated ? It is a very specific to these cars problem that happens to these cars reasonably often. Very few other cars have valve cages. There is nothing to stop them from rotating other than pressure from the retainer nut. Over time the cages can rotate. No tang or anything else to stop movement . Never had one rotate in 40,000 miles and 25 plus years of touring but I’ve helped plenty that were installed wrong or rotated upon installation. Mark the cage so you know you did not rotate it. Once locked down it’s not going anywhere 2 Link to comment Share on other sites More sharing options...
Brooklyn Beer Posted December 23, 2021 Share Posted December 23, 2021 This really makes me want to get a 1917-18 Buick now in the worst way! Almost sounds like working on my Franklin Link to comment Share on other sites More sharing options...
Larry Schramm Posted December 23, 2021 Share Posted December 23, 2021 On 11/22/2021 at 1:13 PM, Tom Devoe said: I need one of these adapters. Can you post what you bought and if it worked as promised? Thanks!! I made my own out of an old sparkplug. Remove the insulator and drill & thread the center of the sparkplug shell. Simple. 1 Link to comment Share on other sites More sharing options...
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now