The not so marvelous motor mystery

[hull 433]

My 1915 is ready for the road but . .

Suddenly her motor won't start. I've previously started it a few times while reassembling the car with no trouble, even on mag.

She has fresh gas, rebuilt coils, a strong spark, clean plugs, fresh oil and turns over readily. I've gone through the Ford manual and Victor Page with no success. A friend who has been driving his Model T for sixty years and knows his Fords is also stumped.

I'm wondering if she is not getting gas - while the line from the tank to the carburetor works fine, and the Holley G bowl is full of gas, I previously had a problem with a sticking 4453A valve. If this is the case, is there a solution outside of sending it off and if not, who is good for that?

She is due for registration inspection this month and it would be good to drive her there. Thanks in advance.

[Retro54]

Assuming you are handling cranking. It took my father a year to learn how his 16 needed to have the fuel, spark, etc. Set to ensure a quick crank start. He too was stumped from time to time. It likely will just take some time to learn your car. Start over from square one a few times and readjust the carb as if it's the first time you started it. My guess is that you'll find the sweet spot soon. Good luck!

[Jim11787]

Also check no exhaust blockage- muffler baffle broken, something blocking tail pipe.

[John kuehn]

If all checks OK besides not starting it has to be no gas or no spark. Having spark and gas it’s either carb adjustment or a loose wire most likely.

If the car has sat overnight and with the key off crank it a few times and stop. Then turn the key on and see what happens.

Make sure gas is going to the carb with the needle set about 1 3/4 turns before turning the key on and cranking. In other words having the carb set a little rich to get it going and smooth it out. One of my cars I use to get it going is this method if it set a while. After I run the car regularly I can set the carb back to 1/4 -1/2 turn. Starts right up every time. If you think it’s the carb tap the carb to loosen the stuck valve inside it.

I have 3 T’s and each one the settings are a little bit different and the spark setting is the same way. Good luck!

[TXGOAT2]

(Key OFF) ... If you open the carb adjustment 1 1/4 turns off the seat and hold the choke closed as you crank the engine for several turns, gasoline should drip from the carburetor. If it does not, you have a fuel or carburetor issue. If it does drip gasoline, release the choke, set the throttle about 1/4 of the way open, set the timing for starting, then turn the key to battery and give the engine several brisk pulls. It should start. If it does not, you may have ignition issues.

Each car is slightly different, but you should be able to easily flood the carburetor (with ignition off) as described above, then turn on the ignition and crank the engine with the choke off until it fires.

It isn't necessary to flood the engine to start it, but doing so will prove that it is getting fuel to the carburetor and that the carburetor is not completely clogged.

Be sure the carb adjustment linkage is actually turning the adjustment needle and that the choke linkage is actually closing the choke fully.

*Remove any air filter and remove or loosen the heat pipe, if necessary to observe the carburetor.

[Humblej]

Stan,
Its either gas, spark, or mechanical. Since it has run OK before lets rule out mechanical. Gas and spark should be easy to check with some simple tricks.

Gas:
1) If you take the bowl off the carb and turn on the gas does gas run out?
2) If you take the spark plugs out are they dry or wet?

Spark:
1) Try starting using a battery not the mag. Do you get a coil buzz as you crank it slowly?
2) Take each spark plug out of the head and with the spark plug wire attached lay the plugs on the head so they are grounded. Do you get spark plugs sparking as you crank it slowly (using a battery, not the mag).

[Vonau]

I'm fairly new to the hobby and have no experience with Model Ts. However, I trained as a mechanic and have often worked on engines.

I would do like this:
Unscrew and clean all spark plugs, connect the cables, hold the spark plugs in a bare spot and crank the engine by hand or with the starter. If there is a spark in all of them, just add a little gasoline to each cylinder and reassemble everything.
Try starting now.
If your engine wants to start briefly, the ignition is OK and the problem is on the carburettor side.
If your engine doesn't work, the ignition point could be wrong or there could be a problem with a valve.

I do this with other engines. I think it should work that way with the T too

[Loftfield]

If all the above fails try pulling the car, key on, let out he high speed clutch to get the engine to turn at a good pace. If the engine starts and runs you then know the problem is some fiddly little setting of carb or spark, just keep fiddling until you find the sweet spots.

[tvw]

While you have a plug or two out checking spark prime the cylinder with some fuel, put it back in and try to start. If it sputters then you know the extra fuel helps. Worked for me!

[Norman Kling]

Be sure the choke valve is fully closing with the choke pulled and completely opening when you let go of the choke rod. If it sticks or only moves part way, you will not get it to start or after you get it running it will be rich and run roughly.
Norm

[speedytinc]

Let me add.
IF your T has the original cam, The timer pin hole is a thru hole. Real easy to get the timer brush off 180 degrees.

Be careful to not over choke.
Thru experimentation, I discovered the key on my 14.
3 - 1/4 full choke pulls. (Adding a 4th choke dont work.) Key on(either mag or battery) 1/4 start pull when cold.
When warm 1 - 1/4 start pull(no choke). I never need to adjust the mixture needle. I could open 1/8 turn to start, but its not needed.

[hull 433]

Thanks for the suggestions! It's raining here today so I'll give them a try this week.

Some observations- the spark plugs are dry when taken them out recently. I'll take them out again to test the spark and firing order. I haven't adjusted the timing brush at all, and it ran with the present setting before.

The choke works properly and I can adjust the needle for a better flow. I've been using a fully charged battery for the recent attempts as well as mag.

This is the forum at its best. Really appreciate it -

[speedytinc]

A spark plug that sparks laying on the head is a good sign but, doesn't mean it will fire under compression.
I had one cyl that was firing intermittently. Tested under compression pressure wouldn't fire consistently.
Closing the gap to .024 would fire as it should.

[Floydv]

Have you tried a compression test?
If you don't have a compression gauge you could just try a squirt or two of oil in each cylinder.
Good luck!
Floyd

[SteveK]

Maybe this is sacrilegious but when I'm stumped the first thing I try is a squirt of starting fluid. It will tell you very quickly if its spark or fuel.

Steve

[Ron Patterson]

Stan
Just a shot in the dark, but you do know how to correctly manupulate the spark lever for hand crank starting?
This is a commonly overlooked step and makes all the difference in the world.
Ron Patterson

[Ron Patterson]

Here is an article I wrote several years ago about the spark lever positioning for hand cranked starting.
Ron Patterson

[Norman Kling]

Some people say to try starting with the lever advanced a notch or two when crank starting. If you do this, with the ignition on, be sure to crank with left hand and as the crank comes up to the top, quickly pull your arm up and away from the crank, also be sure to keep the thumb on the same side of the crank with your fingers. If the crank kicks backward, you have it too far advanced causing the engine to start backward. Very easy to break the arm if it kicks.
Norm

[hull 433]

Put all the suggestions to work and found the cause - a leaky intake manifold.

Fixed it right up and she's back to starting on a quarter turn. Will try starting on mag next. Now to return to our previously scheduled program, sorting out the rest of the car.

Thanks for the advice, support and ideas. It was great to have a bunch of you "in" the garage looking on.

[TXGOAT2]

Good outcome!