Appears to be running on two cylinders

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Unprr
Posts: 53
Joined: Mon Jan 07, 2019 9:20 pm
First Name: George
Last Name: Schmidt
Location: Elkhorn
MTFCA Number: 49710

Appears to be running on two cylinders

Post by Unprr » Wed May 08, 2019 9:03 pm

My question is this.
My T started to run very poorly last year, so I decided to put in a set of new aluminum pistons. I honed out the cylinders and the walls measured stock. With that said, I replaced the original valves with the new type. ( Non-adjustable)
Now that have it back together, it’s very hard to start and when it does start, it runs better with the timer all the way down. It appears to be running on the front two cylinders, since the two back ones still look clean and have the magic marker order number on them.
I have tried timing it by the book, the spark from each plug looks hot.
I need some expert help, on what to try next.

George Schmidt
Elkhorn, Nebraska

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John.Zibell
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Re: Appears to be running on two cylinders

Post by John.Zibell » Wed May 08, 2019 9:54 pm

This should be in the general discussion forum. First thing I would check is for an intake manifold leak where it feeds cylinders 3 and 4.
1926 Tudor


Topic author
Unprr
Posts: 53
Joined: Mon Jan 07, 2019 9:20 pm
First Name: George
Last Name: Schmidt
Location: Elkhorn
MTFCA Number: 49710

Re: Appears to be running on two cylinders

Post by Unprr » Wed May 08, 2019 10:38 pm

Sorry, I did post this on the wrong topic screen..I corrected .

George Schmidt


HaroldRJr
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Re: Appears to be running on two cylinders

Post by HaroldRJr » Thu May 09, 2019 4:33 am

George - Are you running magneto & coils or distributor?


Barry burrows
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Location: Australia

Re: Appears to be running on two cylinders

Post by Barry burrows » Thu May 09, 2019 6:45 am

Have you checked the compression?the new valves May not be seated correctly.

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Charlie B in N.J.
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Re: Appears to be running on two cylinders

Post by Charlie B in N.J. » Thu May 09, 2019 7:31 am

It'd be an educated (slightly) guess but if the markings haven't washed off, after even a slight run, it's a lack of fuel. Vacuum/manifold leak.
Forget everything you thought you knew.


Humblej
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Re: Appears to be running on two cylinders

Post by Humblej » Thu May 09, 2019 9:16 am

George, proper spark advance depends on the engine RPM, it should run better with the spark lever fully down at a high RPM, mid range spark advance for idle or low rpm, fully retarded for starting on Bat, a couple of notches advance for starting on Mag.

I would suggest grounding out one spark plug at a time while at a mid RPM range and listen for a power drop, if there is no loss of power for a given cylinder it is not firing or running right on that cylinder. If you find a dead cylinder or two, I would then swap out those coils with the good cylinders and try again. If the problem moves to a different cylinder you have a bad coil(s). If the problem persists with the same cylinder it could be a timer or wiring problem, or as others have suggested, valves or manifold leak.

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