Ignition problems

JasonNC

My 262 will crank and, with the exception of sputtering slightly, run fine for a few minutes. When the engine warms up, the sputtering gets worse and the timing seems to change on its own. By that I mean the timing mark starts fluctuating and the car backfires and nearly stops. It does this whether I have the Petronix distributor or the original points distributor installed. I'm guessing that the coil is the culprit. And ideas?
Jason

Jon B

Since you're encountering the problem with both the electronic and regular ignition systems, it would seem that the problem lies elsewhere. If this problem kicks in when the engine is hot (rather than just running for a couple minutes) I would suspect the coil. I believe six volt coils are still available (NAPA?) so it wouldn't hurt to buy one and try it. If it doesn't cure the problem, carry it in your trunk, because sooner or later you'll need it anyway and it's good insurance.

[Deleted User]

Check your cap too. A hairline crack and a little moisture play havoc with timing. Even if the looks okay, pick up another one and give it a try.

I suspect that you're right that the coil is your problem. It's not seen very much these days, but spark plug cable insulation breakdown can also cause this type of scenario.

I'm sure you've checked the cables, but in case you haven't, be sure all your boots and wires are free of cracks or damage. If you have wires in looms, ensure there are no chafe grounds or crossfire's. Good luck.

tigermoth

jason, tractor supply corp also has 6 volt coils.
did i read that correctly..your timing is changing? i am not sure how a coil would change timing. like jon says coils can break down when hot and give a weak or no spark, but changing the timing??? if you are getting a good strong blue spark when you pull a plug wire while the engine is turning over would tell you if the coil was the problem. you cannot get a good spark with a bad coil. i would have thought distributor, but you have changed your distributor out.
a few other thoughts.. how does your distributor cap look? (carbon tracking or cracked) how are your ignition wires routed? does the car run differently if the wires are separated? does your car have vacuum advance? or...this isn't an early indication of a timing gear problem is it? does your car have the fiber gears or the aluminum gears? regards, tom

[Deleted User]

Better check that timing chain, must have a lot of slack. That is how they go. Walt.

Unknown

Hello, I had a 1949 Hudson 6 with hard starting problems when hot,that was related to the coil, I had thought it was vapor lock at first.But if the timing is changing, that would be another issue as the timing would be related to the camshaft,if there is extreme wear in this area. Good luck

Park_W

I can imagine that the erratic timing indication could be a result rather than the cause of the engine's rough running. Rapidly varying rpm and vacuum conditions could be reflected in the vacuum advance and centrifugal advance mechanisms respectively. Did this behavior start all of a sudden? I wouldn't think a loose timing chain would cause this behavior to suddenly appear. Although, like other problems, they don't really start suddenly, they just eventually reach the point where they're noticeable.

4starservice

Hi everyone,

I accept all the information offered and have one more thought. It was said that the timing is changing. As Walt said it could be the timing gears. What about the bronze drive gear on the camshaft if it is worn. After I learned about this I pulled my oil pump and inspected the gear for wear. It turned out to be fine but I've noted that someone said they could wear quite a bit in 30,000 miles of driving.

Drew Meyer
1949 Super Six with a little Commodore thrown in

JasonNC

walts garage-53 wrote:

Better check that timing chain, must have a lot of slack. That is how they go. Walt.

Thanks guys for the responses. I converted to 12 volts a while back and I have a 12 volt coil that's relatively new that I can try on it. The coil that's on there now is from Petronix, I had a problem with the first one they sent me with it leaking.

On another subject, Walt how hard is it to replace the timing chain on a flathead? I changed the timing chain on my small block Chevy and it wasn't that big of a deal. The Hudson instruction manual isn't so straight forward as far as simply replacing the timing chain only is concerned.

[Deleted User]

I would have to agree with Walt on this one. Sounds like Timing chain stretch to me.
Could be the Vacuumn advance mechanism but I would lean more toward the timing chain. It is not any harder to change than a SBC would be. Just take your time and make sure the timing marks on the gears are in correct position.
Bob

Park_W

I think the biggest hassle is getting access to the lower front and finding a suitable damper pulley puller that will fit in the limited space. (I've got one, Jason).

JasonNC

In case I need one, where can I find a timing chain?

JasonNC

Well boys, I think we can eliminate the coil. I put another one on and it did the same thing when it got hot. Not only did it start sputtering and cut off, but it wouldn't crank again until it cooled off. I've ordered a timing chain from Dale Cooper. Wish me luck,
Jason

onerare39

Jason,

Been there, done that!

Sounds to me like a text book case of vapor lock. The next time that you get it running, wait for it to die and then remove the air cleaner, then pump the throttle and see if you can see gas squirting down the throat of the carburetor. If not, it's vapor lock.


John Forkner

JasonNC

onerare39 wrote:

Jason,

Been there, done that!

Sounds to me like a text book case of vapor lock. The next time that you get it running, wait for it to die and then remove the air cleaner, then pump the throttle and see if you can see gas squirting down the throat of the carburetor. If not, it's vapor lock.


John Forkner

So what's the cure for that. I vaguely remember as a kid my dad putting wooden clothes pins on his fuel line on a 56 Buick to stop vapor lock. Can't remember if it worked. I have an electric pummp that I can switch on as a backup to the manual pump. No too thrilled about using it as it pumped too much into the carburetor once and when the car backfired, I lost a brand new muffler.

onerare39

Jason,

The cure for me was an electric fuel pump. Having an electric fuel pump should not dramatically increase the amount of fuel that goes into the engine if the carburetor is working correctly (correct me if I am wrong).

Did you get it running again to check to see if there was gas in the carburetor when it died. Also try turning the electric fuel pump on as the car starts to sputter, If it starts to smooth out, it's vapor lock.

John

schillaz

John Forkner[/quote]
No too thrilled about using it as it pumped too much into the carburetor once and when the car backfired, I lost a brand new muffler.[/quote]



It sounds like your pump is too big, try either installing a fuel pump regulator or buy a little 4-7 psi elec fuel pump.

[Deleted User]

Jason, Here is how I fixed mine and have never had a vapor lock since. Run a rubber line from fuel pump to an inline filter mounted on inner fenderwell, then run line to carb. No electric pump. Main thing is to get the fuel line away from the exhaust manifold.
Bob Hickson

[Deleted User]

I would say you better have that carb rebuilt, for as you stated, gas blew the muffler, meaning the needle seat is not holding the gas pressure. Hudson's run good with 4 pounds, so try putting a pressure regulator set at 4 lbs. Walt.

JasonNC

Walt,
You get the Golden Mechanic Award for coming the closest to the problem. I put my spare carburetor on and the car kept running even after it got hot. It's still running rough, which I think may be due to a burnt valve or worse. I'm going to take the head off and see if I can confirm my suspicions. I think you're right about the timing chain also because the timing mark continues to jump up and down and the engine will speed up and slow down by itself. In addition, I probably need a good carburetor rebuilder if anyone can suggest one.

[Deleted User]

Send it to me and get it done right. Walt.

JasonNC

Walt,
It's on the way.
Thanks,
Jason

Uncle Josh

Sounds like Walt's carb rebuild will fix it but in addition, there's a couple of other things to check out, based on what I've run into.

. There were a bunch of replacement jumper wires sold to connect the points with the distributor case. The crimp was so big it rubbed on the breaker plate when it rotated and shorted. A little filing or grinding will fix that.

. I've seen the fine screen inside the fuel pump get so plugged it caused too much of a vacuum in the line and boiled the fuel. Even water will boil at room temp with vacuum on it. The pump won't pass gas, unlike humans, it needs liquid. Clean the screen.

. Before you pull the head, put a vacuum gage on the wiper line to see what it said about the engine condition. Also do a compression test. If it's low, see if a squirt of oil will bring it up. If so, leaky rings, if not, leaky valves.

[Deleted User]

To all, he said he changed the carb and the car now runs even when hot, so everything else must be OK. Carb is the problem, gas running over, stalls engine, and when restarted blew the muffler which had to be full of gas. Walt.