VCCA Home Forums TECHNICAL - 1945 AND EARLIER 1912-1928 A confusing engine problem

As the electrical system has been eliminated perhaps running the engine till it quits with a vacuum gauge installed will determine if the engine dies first and then loses vacuum or loses vacuum first causing the engine to die.

Ray & mOO6840 have some good suggestions; I think the problem must have something to do with the flex or the vacuum tank, IMHO.

Something happened to the car after you had driven it for 300 miles (I assume off and on type of driving) the first time this happened was there anything unusual? Noises, smells, extra shaking, leaks, etc.? Maybe it was because something different happened this time from the other times (reaching at straws here)?

Nope. It simply died out going down the road. Started right up again and started headed home. I wasn't that far from home but it quit several more times before I got there.

I never took it on a long trip. At the time there was a gravel road near where I lived. Round trip down that road was 12 miles. Sometimes I would make several trips a day. Sometimes I never left the yard. There was also a store about a mile or so away and I would use the excuse of wanting a cold drink to drive the car.

You mentioned a burned valve. Could it be...that a rich mixture of gas accumulates in the exhaust system and ingites (maybe with a small backfire) creating enough back pressure to stall the motor. With the exhaust now cleared out it is ready for another "cycle" of starting right up, running for a while, etc.
Dan

One more suggestion. Could it be a head gasket. If the head gasket has a small break into the water jacket, then when the engine warms up the thermostat opens and water rushes in and stops the ignition of the fule and the engine dies. The engine cools a little bit and the thermostat closes, and you can restart the engine. Try this open the radiator cap and watch for the water to flow to see if the water flow occures with the engine stalling out.

My 2 cents...
All the external engine components have been tested or replaced. So maybe the internal parts (the burned valve) or related items are worth consideration. Trying to get this to run well with a burned valve is futile. I would certainly check the carb fasteners for tightness and the intake manifold, the head and the block for cracks or warpage. It could be that as the engine warms up and things heat up a vacuum leak is developing. Pulling the choke out richens the mixture to compensate a bit until it finally dies. The only part I can't figure out is how or why the engine restarts right away. Hmmmm....

Coach

Since we have changed and tested every external component without luck, let's just change the engine.

Just one more thing.

I had a problem like this once on a long run where the engine started to lean out (and backfire a little) and stall. Just pulling the choke about 1/4 got me to the next town.

As an idea,what type of spark plug are you using,and is the heat range the right one for your engine?Too cold a plug may cause enough fouling to kill the engine?Anyone have thoughts on this?

:confused:

If it were bad enough to stop the engine, I submit that it probably would not start back up so soon.

Did you do the "timing light test" at the plug wire or the coil wire?If at the plug wire I would proceed with a compression test first and then a vacuum test as described earlier.Because the engine runs ok at certain times it would help to pinpoint what is happening when it dies.Perhaps lack of vacuum due to a sticking intake valve in the cylinder with a "burnt" valve.If that one cylinder can "pull" a dollar bill at the end of the tailpipe it can also "pull" the vacuum from the intake manifold;especially if the intake valve sticks open for a second or two.

I suspect it will turn out to be something that is so simple no one would expect it, but if the carb has been changed and the car has been run off of a portable fuel tank, by gravity feed and if the car dies then starts right up and if the ignition switch and wireing has been bypassed and the distributorand points are in A-1 shape and the coil, rotor, cap and the high tension wire has been checked for continuity and leakagethen you gotta big problem, there is a pack of Grimlins holed up in your car, It will take a bowtie certified exorsist and a lot of Marvel Mystery Oil, along with a couple of cans of B-12 and some compressed air to get the little devils to turn loose of your car, because it is Hainted and also probably VOODOOED!

all have been discussed the owner has tried all of the above and then some . even the things that does not pertain to four cylinders .need some new ideas on internal problems . i think he needs to pull the head fix the burnt valve and look at the head gasket . and fix all valves and get back later with more details

I agree with Macks idea about Gremlins, ghosts, and voodoo. After all, I do live in South Louisiana.

My health prevents me from doing much of anything. What I have done so far has been time extensive and painful. I'm not whining, I'm letting y'all know that I am trying my best and that it takes me much longer than would normally.

Pulling the head is no longer within my capacity. I'll have to get someone else to do it for me, That too will be difficult.

Bear with me and I'll keep you posted.

Thanks to everyone for your suggestions and help.

OOOPS? I might have missed a post as I can not find the results of the vacuum or compression test.It might sound redundant but the following is from mcgraw-hill/William Crouse cirka 1955 regarding vacuum test-A steady and high reading(17-22") indicates normal operation.At sea level you should be closer to the 22"mark.(2) a steady and low reading indicates late ignition or valve timing;or possible leakage around the pistons due to stuck or worn rings (3) a very low reading indicates a leaky intake manifold or carb gsk or leaks around the throttle shaft (4)Oscillations of the needle increasing with engine speed indicate weak valve springs (5) A gradual falling back of the needle toward zero with the engine idling indicates a clogged exhaust line (6) regular dropping back of the needle indicates a valve sticking open or a plug not firing (7)irregular dropping back of the needle indicates sticking valves that stick irregularly(this one gets my vote-but I would rather have facts than a guess (8) floating motion or slow oscillation of the needle indicates an excessively rich air-fuel mixture (9) a test for compression loss can be made by racing the engine momentarily then quickly closing the throttle-if the needle swings momentarily to 23-25 inches then the compression is most likely ok.I think at this point you should use a systematic approach (as you did with the electrical system) .

There is one good idea about the problem being internal, if the timing gear is loose or some other internal mechanical problem exhists, I don't see the car starting right back up, but any thing is possible in a world run by supernatural beings! VooDOO!..VooDoo! Spiders, Neuts, frog eye brows, and Bat innards, boil, kettle boil, make me up a potion!!

I have yet to do a compression test. I still haven't found a volunteer to step on the starter pedal yet.

But I do appreciate the vaccuum imformation. That's something I can do by myself.

Thanks.

Crouse cirka 1955 regarding vacuum test-A steady and high reading(17-22") indicates normal operation.At sea level you should be closer to the 22"mark.

My response....Today I ran a vaccuum test again. The T I had broke so I went directly off the line from the intake manifold. I had a reading of 17-17.5". Every once in awhile I would attach the line back to the vaccuum tank to allow it to fill with gas again. It ran for 45 minutes before I shut it off. It hasn't ran that long uninterupted for quite some time. Everytime I would start to re-attach the line to the vaccuum tank the engine wanted to stall out. I would have to raise the rpm to keep it running. As soon as I would disconnect that line it would smooth out and keep running at idle. The other day when I tested it I placed the vaccuum gauge between the intake manifold and the vaccuum tank and only had a reading of 15". I don't understand why the reading would be less with in line with the vaccuum tank.

(2) a steady and low reading indicates late ignition or valve timing;or possible leakage around the pistons due to stuck or worn rings

My response....It bounced between 17-17.5 inches. Every once in a great while it would jump or drop .5" but would immediately return to 17-17.5".

(3) a very low reading indicates a leaky intake manifold or carb gsk or leaks around the throttle shaft

My response....Didn't happen

(4)Oscillations of the needle increasing with engine speed indicate weak valve springs

My response....Is that the bouncing between 17-17.5"?

(5) A gradual falling back of the needle toward zero with the engine idling indicates a clogged exhaust line

My response....Didn't happen

(6) regular dropping back of the needle indicates a valve sticking open or a plug not firing

My response....Didn't happen

(7)irregular dropping back of the needle indicates sticking valves that stick irregularly(this one gets my vote-but I would rather have facts than a guess

My response....Didn't happen

(8) floating motion or slow oscillation of the needle indicates an excessively rich air-fuel mixture (9) a test for compression loss can be made by racing the engine momentarily then quickly closing the throttle-if the needle swings momentarily to 23-25 inches then the compression is most likely ok.I think at this point you should use a systematic approach (as you did with the electrical system) .


My response....Several times I opened the throttle quickly and all the way. It would immediately drop to zero. I would not hold it open however. As it returned to an idle it would jump up to 23-25" and then return to 17-17.5"

Tomorrow I'll make a T to fit in the line and allow it to run until it dies of it's own accord.

Somethings not right if it runs better and longer with the vaccuum not attached to the vaccuum tank. Keep in mind I once bypassed the fuel system. If I remember correctly I plugged the vaccuum line at that time and it still quit running. In fact, I know I plugged it. No doubt in my mind.

As I pointed out in the above posting, a disturbance of the vacuum could produce the problem you are experiencing. I suggest that a vacuum leak from the "T" to the dash is your nagging problem. With the loss of vacuum the tank is not being filled as fast as it is used. Even though the vacuum tank has been rebuilt(?) it could also be the problem. Don't know if you have the 4 bolt or the 8 bolt model, but it doesn't matter. If the valve is not closing and drawing gas from the tank that could be the second cause of the problem.

Follow my suggestions in the above quote and find which answer is the problem.

The car is an open car, the wipers are operated by a good friend who would be foolish enough to be with you when you're dumb enough to get caught in the rain.

The vaccuum tank is an 8 bolt model. Are you forgetting that I bypassed the vaccuum tank, or am I missing something here?

Tomorrow, if I can, I'll make a new line to replace the one from the intake manifold to the vaccuum tank. It's new already but I have plenty of tubing laying around. If it matters, it's a 1/4" tube. I was thinking perhaps it's supposed to be 5/16".

I also replaced the intake manifold and gaskets some time back thinking the problem might lie in there.

Have you had the exhaust manifold off the head? It looks to me that you have checked or eliminated every thing else, except the Grimlins of course. and are you getting good flow out of the tailpipe? When the engine runs does it accelerate up to speed (40 MPH) ok?

If your car is a touring there is no "T" on top of the vacuum tank. The line from the tank to the intake manifold is 1/4".

I think you have found your problem. Replace the vacuum tank. If you replace it with an 8 bolt model then the restrictor must be REMOVED from the intake manifold. If you replace it with the 4 bolt tank then it MUST have the restrictor.

Mack, Going down the road the engine runs fine...until it stalls out. It will accelerate to 52-55 mph w/o a problem.

Yes, there is plenty of exhaust coming out of the tail pipe. The vaccuum test also assured the exhaust system was in working order.

Ray,

Bear with me, maybe I'm being especially stupid here.

The vaccuum tank has absolutely nothing to do with the problem as far as I can tell. I have bypassed it in the past and gravity fed gas directly to the carb and the problem remained.

The "T" that I mentioned was an adaptor that came with the vaccuum gauge. With it you could hook the vaccuum gauge to a line w/o disconnecting what ever it was that the vaccuum line went to.

What restrictor are you talking about? Is there something in the intake manifold that I don't know about?

Why replace the vaccuum tank if it is functioning?

You really lost me this time. :confused:

From your given data I am convinced the vacuum tank is your problem. You are loosing so much vacuum that the tank can't keep up with the fuel need.

At the time you were using a bypass fuel system what was the condition of the vacuum line? Was it blocked off or left open?
Seams like the answer to me.

The restriction is in the fitting that goes into the intake manifold. Do you not have a copy of the OM and Maintenance Manual?

Hi rbl2
Here are the restriction Ray talking about



Regards Arvid

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