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Stalling 1938 Studebaker? Any ideas?


SC38dls

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6 minutes ago, SC38DLS said:

TerryB good looking pup. A golden I assume.  

Yes, that was Boomer, we had him for almost 15 years. Wonderful companion, a friend to everyone he met.

 

As for my lawn mower gas tank comment, it was from a used lawn tractor to be big enough to supply gas to an  automobile carburetor.

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23 hours ago, Frank DuVal said:

 

Right, find TDC for the #1 piston, and see where the pointer is in relation to 0 on the timing mark (on damper in your picture). If the pointer does not point at 0 when the #1 piston is at its highest point, something has slipped a tooth OR the vibration damper has slipped on the crankshaft

 

I had to think about this.

I don't think one could determine a jumped gear or chain this way. Slipped damper, yes. Distributor gear yes. But not cam.

But yes the ignition could be off as a result of a jumped gear or chain, which ever this has as the distributor should be running off of the camshaft.

I hope I am seeing this correctly.

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17 minutes ago, JACK M said:

I don't think one could determine a jumped gear or chain this way. Slipped damper, yes. Distributor gear yes. But not cam.

 

Of course, "normal" engine in this case, spending too much time with Corvair engines, since the timing mark is on the crankshaft and the piston is on the crankshaft...... no way can cam or distributor timing be tested this way (unless a Corvair, where the distributor is driven off the crankshaft 😉).

 

So, this is a test of the timing mark on the damper. A good test, as the dampers do fail (slip), depending on construction.

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I’ll have to get back to you on all of this. At vet now as one of the pups is having a problem. May be a few more hours, so not likely to do much today. 
one thing I did do was the fuel flow test from the tank thru the electric pump. The pump is rated at 4psi with a 30 gal per hour flow. I got a half gallon in a minute so that is good and it does not look like the flow is blocked at the tank or electric pump. I have a setup for the gravity test using a lawn mower tank hook up under hood. I want to do the timed flow test between the mechanical pump and the carb first, then I’ll try the gravity feed test. 
One question what should the flow out of the mechanical pump be, the same as the electric or would it be lower? I don’t have manuals with me to see if it is listed there. 
dave s 

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Way back in that link to 41 Champion (same engine) tune up specs, in the small light print, used a 24" monitor...:

 

Pressure: 3 1/2 lbs maximum 

Capacity: 1 pint or over in 1 minute.

 

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TerryB film at 11. !!!! 
four plus hours at vet and all is ok. Minor infection should clear up quickly. 
 

Hopefully I can get back to this early tomorrow and get it resolved.  Gravity test will at least solve the fuel question and if that comes back good then it will almost have to be timing and/or the vacuum advance. I’m leaning toward that thinking how this got progressively worst as I drove it. I’m wondering if the distributor clamp worked loose because the advance diaphragm was messed up. Don’t know if that is possible but if it’s the last thing I check it’s my luck that is what will be wrong. Time will tell. 
 

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Gravity feed alone - no change

Gravity with electric pump no change

Gravity with mechanical pump no change

Gravity with mechanical and electric no change. 
 

I don’t think it’s fuel flow. 
 

checked timing and still way before TDC and even more before IGN 

Next will check heat riser wired in opposite position it is in now and recheck timing. 
 

Maybe it’s time for a SBC and auto trans! 😳 
No not going to happen at least not in the for near future. 

 

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On 3/18/2021 at 10:29 PM, Frank DuVal said:

 

It happens this way EVERY time? Starts great, idles great, just won't develop any power after a short time? 

 

Drop exhaust pipe from manifold. If safe, drive it that way to test. Might not be safe, maybe just drop muffler off. I know, rusty fasteners make any part of this test hard to do!🥵

 

Partially clogged exhaust system makes this low power issue*. Completely clogged systems make it not run, not even start in most cases! The old potato in the exhaust pipe trick...😆

 

* extremely common on GM systems of the 70s, a double wall exhaust pipe collapses internally with NO external noticeable distortion. Have to drop pipe off to test run.

 

Time to revisit this from page one of this thread.

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Ok I took it to the carb man. He confirms fuel flow is good, vacuum is good, timing is good, points are set correctly, plugs are good. Exhaust is good. He is as baffled as I am. The only thing he said is the valves may be too tight but the way it starts and idles that does not make any sense. Both he and another mechanic in the shop said they have never seen a flat six start and run so well then have this problem. He is going to check with an old guy that rebuilds flat heads and see if we can’t take it over to his shop. I at least know some people that may have an idea what is going on. I’ll let you all know. 

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Could it be something with the transmission or anything else on the drive line that could be adding to much load on the engine when you start to drive the car? Something binding in the transmission? Shift fork and gear? Clutch pressure plate issues? Clutch assy? Differential? Just putting it out there since everything else from the transmission forward has been checked out. Stranger things have happened.

Edited by Laughing Coyote (see edit history)
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1 hour ago, SC38DLS said:

Exhaust is good.

 

What test did you perform to determine this result?

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The carb guy did the exhaust test and I have no idea how to even explain what he was doing. He said the best test would be to cut the exhaust pipe about two feet after the manifold as the bolts are two rusted to remove without possibly breaking  something. Then reweld it after testing. I know it did involve the heat riser and manually holding it in both positions and doing something at the end of the tailpipe while the other fellow did something at the carb. He originally thought the heat riser was stuck but quickly determined it was not. He still suggested to remove the heat riser as the spring is gone. I will probably be doing that as soon as I can. 
The wipers are vacuum system, we checked for leaks and there does not seem to be any but we have disconnected them and plugged the vacuum tube as a precaution. The only vacuum line being used is the one for the automatic advance on the distributor. 

Edited by SC38DLS (see edit history)
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Padgett that didn’t work but at least he is so intrigued he is asking some other guys that work on flat heads what could be wrong. Hopefully someone that understands this motor a lot more than I do will have hands on and it gets resolved. 
The fact someone that knows carbs and fuel systems as well as he does says it makes no sense this thing runs so well at an idle and starts so easily then does what it is doing under load. 

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He did a flow test just like I did and two or three of you all suggested, using starter fluid at the carb but he had a vacuum gage a (I believe) a dwell meter and an rpm meter hooked up and there was not any change in any of them. He said the same thing Ed said, the rpms should have changed. He had so much hooked up I didn’t know what to look at first. He added things as it got more frustrating to the two of them. Each time he did something he said that eliminates x or that eliminates y. 
I wish I could have taken a picture of their faces when they finally said “This makes no sense, I’ve never seen anything like it. A flat head isn’t that complicated and this can’t be happening”. 

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You can welcome those guys to the Studebaker Dazed and Confused (SDC for short) club that have been watching or contributing to this thread Dave.  
 

Rolling freely sure makes brakes seem unlikely.

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I try to be intelligent about troubleshooting and believe in instrumentation but sometimes having a second one and swapping parts until something changes is the only answer. Then hindsight can come into play.

 

Has to be one (or more): suck, squeeze, bang, blow. Is all there is to an otto engine.

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Just so you know the carb guy’s shop has 6 or 8 bays with cars in each one from MG TD’s, a Jag, a Fiat 124 to 60’s Chevys and Fords. He also had 6 or 7 cars in the fenced in yard with at least one T waiting to be fixed. He is supposed to be the guy other shops send cars to for carb work. He’s a character and is probably in his mid 60’s. He laughed when I told him I was told he’s the guy to go to for carbs. His comment was “The guys that need code readers have no idea what a carburetor is! “ 

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So how goofy an idea is trying to pull out in 2nd gear to rule out issue with low gear in trans?  Maybe on a slight downgrade to be kind to the clutch.

 

Ok, more brain input, so you drove it to the carb guy which means you drove in all 3 gears so selected gear doesn’t seem to matter.

Edited by TerryB (see edit history)
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35 minutes ago, SC38DLS said:

He said the best test would be to cut the exhaust pipe about two feet after the manifold as the bolts are two rusted to remove without possibly breaking  something. Then reweld it after testing.

 

That would test it, however my mantra is "do on harm" and I would never do that to a customer's car. For what it is worth, there are or were kits to drill and tap a hole in the exhaust pipe to check for restriction. Exhaust restriction is fairly common on catalytic converter equipped cars, and that is why these kits existed. A fitting screwed in the hole and you could attach a fuel pressure gauge (this is usually the same instrument as a vacuum gauge, with 2 scales and zero in the middle) and drive while watching the exhaust pressure. The kit had little plugs to plug the hole afterward. I would not drill a hole in a customer's exhaust either, and never did, but it sounds a lot less invasive than what is being proposed, so I'm throwing it out there. If it were me, I would be soaking up those manifold bolts or studs every day with heat riser solvent, in anticipation of possibly having to unbolt the exhaust.

 

45 minutes ago, SC38DLS said:

I know it did involve the heat riser and manually holding it in both positions and doing something at the end of the tailpipe while the other fellow did something at the carb.

 

I can't even imagine. Maybe he was testing for something else? Inline engine heat risers typically don't do anything other than redirect the exhaust up or down.

 

47 minutes ago, SC38DLS said:

He still suggested to remove the heat riser as the spring is gone.

 

I hate to be blunt, but this says he doesn't know what the hell he is doing. Heat risers aren't rocket science, and they are not overly aggressive in 1938 like they were in the 20s. If a Studebaker spring is unavailable, most likely a spring from some vehicle with more reproduction parts available will work.

 

Can the problem be duplicated in the shop? Will it screw up if you just rev it up a little and hold it there? Or do you have to drive it and put a load on it?

 

I wish I were not 5000 miles away. I'll bet if I were there I could figure it out. How far is Ed?

 

 

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I just had my 2nd Covid shot two hours ago so drug induced ideas might be happening.  Two ideas if you choose:

 

1. Replace the high voltage wire from the coil to the distributor.  It’s a common link that feeds all cylinders.
 

2. Take the spark plug wires out of the metal guide and route them with no wire to wire contact and no contact with any metal.  Looking for cross arcing at higher RPMs.  
 

 

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Bloo. He did not want to destroy the car exhaust either. He said that would be away to prove without any doubt the exhaust was not plugged. He did not want to try the bolts as again he did not want to possibly break them off. His comments about the heat riser was because the spring was missing and in the south it probably is not necessary and if it is getting stuck it’s one way to solve the problem. Don’t forget he tried everything and nothing was making sense as to why this is happening. That’s also when he mentioned the tight valves but again he said it makes no sense as the car ran well two weeks ago. That’s why he wants to talk to someone that knows flat heads better than he does. 
As far as Ed, this man has done exactly what Ed suggested doing and can not figure it out. 

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TerryB if we had cross arcing would we have good spark at the plug?  I will keep it in mind but hold off until I talk/see the flat head guy. I think I would have to get another set of wires as I would probably destroy them getting them out of the metal guide. 

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9 minutes ago, SC38DLS said:

TerryB if we had cross arcing would we have good spark at the plug?  I will keep it in mind but hold off until I talk/see the flat head guy. I think I would have to get another set of wires as I would probably destroy them getting them out of the metal guide. 

I would think good enough to run at low speeds. Any small high voltage leakage would not be as noticeable until the engine rpms go up and any leakage becomes more consistent, that is, the plugs are firing much more often and a loss of energy becomes more noticeable.  There have been instances of the coil and / or spark plug wire being bad internally as the brass connectors are corroded where they come in contact with the core of the wire (had a mc with issue) and if they are resistance core wires the resistance material was no longer as conductive as it should be.  Just thinking out loud here to see if anything makes sense.

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Maybe. Electricity always takes the shortest path to ground.

 

The maximum voltage is set mostly by the plug gap, but it is really the sum of the plug wire resistance, the resistors in the plugs (if any), the plug gap, the carbon button in the distributor, the gap at the tip of the rotor, and anything else that causes resistance between the coil tower and the case of the plug where it grounds to the head.

 

The resistors in the plugs (if any) and the resistance of the plug wires are so small compared to open gaps that they can pretty much be ignored unless they are bad. If there is a bunch of extra resistance in a plug wire, or a coil wire, or a plug, or whatever, the voltage will go much higher than normal, and the insulation will have trouble keeping it in. If it can jump to ground somewhere without going all the way to the plug, it will. Voltage is highest when pulling a load.

 

If the wires are not that fragile, you could just ohm test them with a DMM. It is hard to get a good connection with your probes, but be persistent. An old non-resistor spark plug can be useful for getting a connection on the plug end. Test from the center electrode to the other end of the plug wire, or better all the way into the contact on the inside of the distributor cap.

 

This won't tell you anything about the insulation, but in my experience insulation failure almost always starts with high voltage caused by a bad plug wire or some other high-resistance fault. Check that the carbon brush in the distributor is there, and that it is indeed touching the center of the rotor. I believe you said the rotor was new (?), but try a different one anyway, maybe your old one. Look over the cap under a bright light for carbon tracks.

 

If the wires are too fragile to mess with like that, buy the cheapest set of 7mm plug wires you can find for whatever car (look for a set with a coil wire that is long enough) and substitute them temporarily.

 

Let us know how it goes with the flathead guy :)

 

 

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Know anyone with an ignition analyzer ? (multi lead oscilloscope). Are a couple on eBay including a Heath for a buck and a half but do not know if it includes the leads (important). There is nothing like having good instrumentation.

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The plug wires are not fragile but they run thru a metal protector (for lack of a better description) so would need to be taken apart as the ends will not fit thru the tube to split up like TerryB suggested.  Once I talk with or hopefully let the flat head guy see the car I will get the plug wires and give them a try. Can’t hurt and by if that doesn’t work I have an extra set of wires. Just like the electric pump, points, rotor, plugs, coil, cap and condenser. It never hurts to have spares. 

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Padgett, I do know a guy that has all kinds of test equipment. He even has a big SUN analyzer! Problem is he is in Chicago about 800 miles away. I don’t know anyone around here. We haven’t even met the lady next door because of COVID-19. 

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1 hour ago, SC38DLS said:

The plug wires are not fragile but they run thru a metal protector (for lack of a better description) so would need to be taken apart as the ends will not fit thru the tube to split up like TerryB suggested.  Once I talk with or hopefully let the flat head guy see the car I will get the plug wires and give them a try. Can’t hurt and by if that doesn’t work I have an extra set of wires. Just like the electric pump, points, rotor, plugs, coil, cap and condenser. It never hurts to have spares. 

When I sold my 37 Dodge pickup I pretty much filled the floor of the bed with spare parts.  When I decided to sell it I went searching for all the small spare parts I had and was surprised at how much I accumulated over the years.  The new owner was quite happy with the stash and I just felt like that squirrel who stores nuts for the winter and then forgot where he put them.

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Dave, I'm sorry for all the grief you're having.  By all means, try a new coil wire first, or just make one--I keep a fresh one in shop to validate what's on each car if I have a problem.  Look for corrosion in the coil tower which receives the high tension (large diameter) coil wire.  And carefully inspect interior of cap with strong light.

 

I'm confused, though.  You said you measured 14" Hg with your vacuum gauge then later said that a mechanic said vac was ok.  Vac should be 18-20 at idle near sea level.

 

Can you borrow an entire distributor to substitute?

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Grimy. Do all cars have a vacuum of 18-20? 
His comment was for vacuum leaks, I’m not sure if he was worried about the actual reading of 15-16 as opposed to 18-20. 
 

I’m going to get a set of wires and try them. If that doesn’t work then I’ll try the distributor. 

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