How can I tell if the cam timing is a tooth off in my '51 Ford Coupe stock 8BA flathead? Is there a simple way besides tearing it down and checking the timing marks? Years ago this engine used to be really snappy for a stock engine, second gear bark the tires even. I had sold it many years ago with it being gone 32 years. Since I got it back several years ago it is really doggy. I have a '51 moredoor and it will run circles around the Coupe, revs a lot faster too. I don't want to tear it down if it is just tired but I sure would like it to run right. Hopefully someone can tell me how to check it out! Dave
Pretty much all V8 except Nailhead, #1 cylinder at TDC compression, #6 valves should be at overlap. And vice versa, I think I have that correct. It is possible to check anyway, somebody will correct me if this is incorrect.
8BA has a groove on the pulley and a mark or pointer, right? If so, line those up just after the compression starts coming out of #1 plug hole, you should be at TDC. Blow air into the hole and see/listen for it leaking out somewhere. But my guess would be after 32 years it's probably tired. I'd first run a compression test and see what it looks like.
You should be able to remove the front cover in order to check the timing marks. Do you know what the cam is, stock or reground? If you know the timing events, you could indicate off of #1 exhaust valve which can be seen with the plug out. Will need a degree wheel and a dial indicator.
All stock engine. I put a new timing gear in years ago, fine after that. Next owner was into the engine years ago, not sure what was done but left it stock. I know I can see timing marks with cover off, that's what I was hoping to avoid. I don't have a dial indicator.
Other than having to get down low and contort your head in there, pulling that cover off ain't such a big deal.
maybe find out what was done?? cam timing isn't the first place I would start with an engine like that. make sure all the other things are correct first. compression, spark, carb.
Remember that it's gear drive, and a tooth off is quite a bit. Cam gear failure can happen with the fiber gears, but generally results in immediate immobility and dead silence as you coast to a stop. look at ignition/carb type details, scrutinize plugs for any that don't look like their 7 friends. Reminds me a bit of an ancient diagnostic manual I have somewhere...the guy who wrote it was obviously obsessive/compulsive and listed everything possible under every ailment with no filtering for likelihood. Gas mileage down? Top of the list might be "broken crankshaft."
For the 1st 17 years it got used and taken care of. I even borrowed it back a couple times. He then sold it and the rest of the time it sat in a carport. I got it from that owners son. Tires on one side were sun baked, other side was like new. I did the air pressure test today at TDC and it does leak back through a little so what does that indicate? I also did a compression check. 75-80 lbs across the board. Seems a little low. It idles very slow and very smooth. All the plugs are a nice light brown. It is just very lazy running. I put a new timing gear in a '29 Model A once and got it a tooth off. Drove it for 3 days straight and it ran sluggish. Fix it right after I got home from the trip and it woke back up. Hoping the '51 is suffering from the same thing. Dave
If it still has the stock distributor, test the vac advance for leaks/working correctly. Fiber cam gears can be worn a lot and still function.
If it leaks back through it is an indication that a valve may need to be touched up. Here is something that happens. When you park one and do not back the valves off the valves that are open more often than not get a little surface rust from the moisture in the air, sometimes worse than surface rust. A lof of the time a good lapping with cure it sometimes a valve grind is in order. Another things that happens is that the sprigs that are partially collapsed get weak and do not fully close the valve.
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