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Doug&Deb

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Okay here’s an update. Tried everything except valve adjustment. That’s next. I even ran new rubber line from tank to pump with nothing in between. No change. I’m lost here. I find it hard to believe that 4 coils 2 carbs and 3 condensers all went bad at the same time just to irritate me.

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29 minutes ago, Doug&Deb said:

Okay here’s an update. Tried everything except valve adjustment. That’s next. I even ran new rubber line from tank to pump with nothing in between. No change. I’m lost here. I find it hard to believe that 4 coils 2 carbs and 3 condensers all went bad at the same time just to irritate me.

 

What is the coil primary resistance on the coils you have used? They're are going bad for a reason. If you have too much current(amps) going through them they will get hot and eventually fail. For a 6volt system, you don't want more than 4 amps running through them.

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53 minutes ago, Doug&Deb said:

Okay here’s an update. Tried everything except valve adjustment. That’s next. I even ran new rubber line from tank to pump with nothing in between. No change. I’m lost here. I find it hard to believe that 4 coils 2 carbs and 3 condensers all went bad at the same time just to irritate me.

Hide the hammers. You haven't seen me with my old truck sometimes.  It can be irritating.   What about the wire in the distributor?  Think others have had trouble with that, but don't know about the symptoms.   These things don't slip timing chains, but wonder if something like the spring advance in the distributor broke?   One person said to check the base where the carb fits (not the carb) for leaks.  How was that?    Did the problem start gradually over time or suddenly? Would think valve adjustment problems would be a gradual issue that would get progressively worse.   If all else fails pull the muffler.

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16 minutes ago, Doug&Deb said:

What would cause that? It ran fine until recently.

Before in Oct 21 you had the same problem but said it was okay after you put the old carb back on.  https://p15-d24.com/topic/56707-carb-issues/?do=findComment&comment=609787    I noticed on this post you said both carbs had been rebuilt. When you corrected the same problem previously by swapping carbs, did you later rebuild the old one that was working?

 

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24 minutes ago, Doug&Deb said:

What would cause that? It ran fine until recently.

Carb base leaking doesn't usually happen suddenly. Neither do valves getting out of adjustment.  Something breaking loose like a piece of trash on the float valve would happen suddenly, a spring breaking would be sudden, maybe condenser going bad (anybody?).   I know my freaking muffler got suddenly loud over a few days and made me think the manifold Y pipe gasket blew (nope).   Before anything else -> Humor me -> On that sisson choke.. warm the car up and wire the choke plate on the carb open so it can't possibly move.  

 

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The carb problem in October was resolved with a rebuild. I think lol, that was a while ago. I checked for vacuum leaks and there’s none. I’ve tried multiple condensers. I even swapped out the distributor with a spare. I’ll check the coil resistance although I’m not sure what would cause the coil to go bad. Whatever the root cause is eluding me. 

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See a lot of good pokes in the dark here ..... First thing is I do not see the original problem you are trying to solve ... this thread is a continuation of a different thread that describes the problem there?

 

Losing the cloth wire covering in the distributor was a real issue for many. It is a ground wire, since you have a positive ground electrical system, when the cloth covering falls off & the points plate moves from the vacuum advance the wire can spark, ground out against the distributor housing.

 

The hot coil is a clue.   If you are using a used coil for testing. It should not be hot.  .... Just because we can swap 6volt or 12volt coils around & your engine will start & run .... does not mean it will run well.

Some coils have a resistor built into them, some need a resistor added before the coil.

If it is a used coil, possibly a 12v neg ground coil ... swapped into a 6v pos ground vehicle.  It should work ... kinda.

Because I am very stupid on electrical .... I want to call it a sine wave? ... A pos ground coil is use to running electricity in one direction, when you swap it with a neg ground coil it is now running in a different direction. ..... this can cause some really strange issues, probably more noticeable at higher rpm.

Jus thinking that a good working used coil seems harmless, you need to know it's past polarity & also if you need a resistor or not with it.

 

The 3 bad condensers .... absolutely.  I honestly think it may have been my bad luck to buy the condensers from NAPA auto that week.

Possibly if I went back 3 months later they would have had a better batch shipped in from over seas .... yes 3 bad in a row is documented in my diary and the 4th came from a junkyard & worked fine.

 

Of course I have no reason to reply to this thread, I never saw what your original issue is. I just saw some of the past replies & toss a shot in the dark.

 

 

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Do you have a Vacumm Advance on the Distributor? When they go out you lose power.

Take it off and check it out. I also go with the idea that the Internal Distributor Wires need inspecting.

Adjusting Valves is not needed if you do a Vacumm Test and get a steady Needle/Hand between 17-21".

The fluctuating Needle will tell if you have a Valve problem. Hook it to a Vacumm port and run engine ti Diagnose.

No need to tear an Engine apart until properly Diagnosed.

Tom

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Here is one more thing to consider.  A new station opened in town that sells alcohol free fuel.  I tried it in the 47 P15 and the old Jeep.  They both run better on the alcohol free fuel.  Tried the alcohol free fuel before I adjusted the valves.  Had more power but still idled lumpy.  Then after the valve adjustment it runs like I remember them running when I was a kid.  The flat 6 can be idled down so low you can almost count the hits.  But that was just for fun - then I took it back up to the correct idle.  

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Others have mentioned a vacuum leak . That might be the problem .  Check under the middle runner on the intake.  They can be prone to cracking.

 

If you squirt oil over it , the oil will be drawn into the crack.   You could also use propane  but there is a significant hazard of fire.  

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Thanks for the suggestions. A friend of mine is a far better mechanic than me. He’s going to take a look. I need to walk away for a while. Both of my dizzys are rebuilt with new wires. Nothing looks amiss in there. I have 17 on the vacuum gauge at the port on the intake manifold with no fluctuations. No leaks around the carb. I’ll check around the manifold for leaks. Need to check fuel pressure to see if the pump is going. It’s only a year old but you never know. If I ever figure this out I’ll let you know.

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Removing the line at the tank is the next thing. I have a question about that. I’m aware of the ferrule in the line but is the fitting still a 5/16 inverted flare? That first foot of the line is original and the new line is spliced to it. That may be where the problem is. 

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If the issue is fuel delivery, don't forget the pickup line in the tank.    I'm not sure what your tank history is, but old gas varnish build up will restrict the filter, lines break, rust, develop pinholes etc causing problems.  My '56 has a standard inverted flare fitting.  but it is different in several ways from the earlier ones.

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