Idles fine but...

[jwaldrich]

Dug out car that set fot 2 years. It idles fine but misses bad when you give it gas. Mixture changes don't help. Known good coils helped but wasn't a complete answer.
Gas was drained so I put fresh gas and changed oil.

Starts very easy and when warm idles nicely.

[Farmallcub49]

Timer dirty or timing off.

[jwaldrich]

I cleaned the timer.

Timing off? Please make me smarter. I though timing was controlled by the spark advance lever.

"Supposedly" it ran fine "when parked".

[Farmallcub49]

Here is a really, really simple method, just follow the link and then click on the pdf

http://www.spokanemodeltclub.com/how...-a-model-t.php

[Royce P]

Every car that is for sale ran fine when parked. Of course!

Seriously, if this is a car you just bought, you may need to go through all the basic stuff.

1. Is there adequate fuel flow to the carburetor? Try at least 5 gallons in the gas tank. If the fuel strainer or the carburetor needle / seat are clogged with dirt having more gas in the tank can over come the problem. You still may have to clean all those things to get permanent good results.

2. Bad connections in the coil box - this is a common problem. Usually the only way to be sure is to take the coil box completely apart and clean everything, and re - solder all the wires. John Regan sells a coil box rebuild kit that is a good excuse to do this - click here:
http://www.funprojects.com/products/5000RK.aspx

Originally Posted by jwaldrich

I cleaned the timer.

Timing off? Please make me smarter. I though timing was controlled by the spark advance lever.

"Supposedly" it ran fine "when parked".

[jwaldrich]

Sponsored Links (Register now to hide all advertisements)

Swapped carbs to a known good carb. No change.
Swapped coils to known good Ron Patternson coils. No change.
Drained sediment bulb. See what I found!


No change.

Pulled and blew out fuel line. No change

Disassembled and clean carb. No change.

Compression test with crappy gauge. 30 pounds across all 4 cylinders, twice.

Haven't checked the intake manifold for critters.

[jwaldrich]

It's an old Anderson timer. Thought about replacing it but haven't... yet.

Sprayed brake cleaner at each "raised valve" through the spark plug holes today. Didn't seem to help any. They all went up and down but obviously no measurements were taken this way.

Also pulled the sediment bulb and disassembled that. Beautifully clean with nearly zero sediment on the screen. Bottom of the fuel tank is bright shiny galvanized although the exterior shows it is probably a replacement tank/not original issue. SO.. the fuel system is/has been clean from the beginning.

At this point I think I am leaning with those who feel it is timing or in the ignition somewhere. Work on that next.

[Tom RSA]

I had a similar problem on my 1923 a few years ago. It would idle fine but started missing as the revs went up. One evening the car was idling in the workshop and the mains electricity in the workshop went off. I noticed a spark jumping from the timer wiring loom towards the coil box terminals on the car. The next day I removed the loom and noticed that the insulation on the wiring loom had failed in a few places.. Wrapped it with insulation tape and the problem was gone. I have since fitted a new loom.

[jwaldrich]

Ran it in pitch black garage and saw one intermittent spark on the fire wall near the choke lever and fuel air adjustment rod.
It seems there is an issue in the coil box.