Projects Mild custom '51 Pontiac Chieftain

Out of curiosity, exactly where did you apply the fresh solder? How did you hold the brushes back while you reassembled it? Was there a significant increase in rpm running it on 12v, enough to cause other physical damage?
I ran the 6v heater fan in my '29 pu on 12v for a couple of years before it started to rattle then quit. I never attempted a repair, I just replaced the whole heater with a universal aftermarket unit.

 

My 6 volt heater runs fine on 12 volt, I put a 1 ohm 100watt resistor in line and mounted it in the air duct which cools it as the fan runs. Might work for you.
Enjoy your posts!

 

Well, there's reason behind it- my wife said I already spent $40 on gloves, oil and grease so apparently to ask for more was pushing my luck. So, that left two options. No motor or try fix broken motor.

Each commutator connection has a little lug that the rotor windings are threaded over. This had become too hot, melted the solder and flung it all off, losing connection to the windings.
I held the brushes back by putting them in place with a screwdriver, pushing my finger down on the connecting braid so it couldn't move, don't the same to the other side then wiggling the rotor in past my fingers into the bearing. Easy? No.
I will see how hot this one gets on 12V and determine if I need to change the motor or amend the circuit. It spins noticably faster but the fan is well balanced, enough that it doesn't cause a problem.

Yeah, there's space to cut a hole and mount a high wattage resistor in line, that's certainly an option. I'm thinking one designed to make heater fans have multiple speeds, they're set for that kind of work.

Phil

 

Tonight I emptied a significant amount of Alabama out of the ductwork and set about on one of the sheet metal pieces from under the car.

Looks like someone had jacked the car up onto it. Little wonder the air wasn't coming through very fast.

I beat on it with hammers. It's not perfect but it's better.

Tomorrow I'll see what temperature the motor gets up to running on 12V.

Phil

 

Nice little pile of dirt. When I had my '56 Chevy apart I swear I got about 3 pounds of eucalyptus leaves, dirt, rust and old paper and rags out of the vent and heater ducts. Needless to say I had to do a little rust repair too. I wish my Chevy heater had a little more uumph to the air flow.

 

After a few hours the motor was at the ambient temperature inside the garage, 59F.

Running at 6V for about 15 minutes, measured again.

A modest 75F (though the end by the brushes was about 80F).

Bumped it up to 12V.

Nearly 90F with the end cap peaking at about 106F.

I'll pull it apart and see if it shows any signs of distress.

Phil

 

I found a lot of places that air was leaking out. At 6V the thing has fairly decent push but it's moderately insipid. The leaky ducting doesn't help that at all.
12V it's significantly better but as you see the additional heat in the motor is a moderate concern.

Phil

 

Wiped the dirt off one side of the fan clamshell with a damp cloth. It came up looking nice.


Knocked the old underseal off where it was still attached to the ducting.


Wire wheel, cup brush...


Looking more presentable and protected.
I like gloss black.

Phil

 

Rewired, reassembled and now reinstalled in the car. It works.

 

Old electrical guy here, had lots of ground problems... - Is this fan housing well grounded? Maybe another ground wire to a body ground.

Looks great,
Russ

 

It is, that is duplicate of the original wiring. The inner clamshell is very well bonded to the car, that brings the rear housing of the motor (which is the shortest ground point and also because the motor is mounted on rubber) to a well grounded location.

Phil

 

Now it's light, a few pictures.


Fan intake pipe, up in the wheel well.


Floor heater duct and pipe. I had to lower the car down onto a jack stand under the pipe to bend it to the correct shape- it was a few inches out of line and I couldn't tighten the bracket.


Finally, the fan. Best picture of it, all tucked away down the back of the engine compartment.

Phil

 

Ooh, I do also understand the irony, I have fixed my heater just as we got our first 80+ degree day.

Phil

 

Time for another Malted!

 

No chocolate malt tonight.


Washed and leathered the car. It was covered in leaves and bits of trees. The trees around here think it's fall.



Phil

 

I wired the electrical fuel pump up to a switch. In traffic it clears any vapor locking before the mechanical pump and at high highway speeds (55-60) it appears to be keeping the float level correct in the bowls.

Not the most sightly thing under the dash (bolted through a factory hole) but it for sure works and makes the car a lot more driveable.

Phil

 

Finally, time to go get a chocolate malt!



Funny how modern pickup trucks absolutely dwarf the car...! Not that it's a small car by any means.

Phil

 

I put a tee at the manifold and attached my vacuum gauge. I set the idle mixture because the engine was nice and hot. I set the timing also for the weather.

Runs better now, doesn't pop and bang on overrun either.

Phil

 

I had a go at setting the ignition by ear; that was ok but to try and get it a little closer I had my wife hold the brakes and push the gas to the floor in gear briefly- against the fluid coupling that stalls about 1500 rpm under load I tweaked the timing for maximum RPM. I need to back it off a little because peak torque is meant to be 2200 rpm but that's got me right in the middle of the ballpark.

It'll very nearly leave a black line up the street now if I punch it... That's too low down in the rev range.

Phil

 

Hey Phil,
I am still enjoying your posts!!
When you set timing do you disconnect and plug vacuum advance? My 53 Chieftain has a metal vacuum advance line and the service manual isn’t clear on setting the timing. I also have a little pointer and graduation marks to set it on the road I think. It runs so good I never adjust it but I need to give it a tune up and need to know how. (On my off topic 64 Pontiac that starts with the letter G and ends with the letter O has a rubber vacuum line that is easy to remove and plug)
Greg

 

Please keep posting. I am enjoying your stories of how to enjoy an old car without braking the bank, and fixing stuff instead of replacing it.

 

Well, that depends on the carburetor. I have a Carter WCD on mine, and this is based upon that being the case.
Short answer, no. I do not plug anything when setting the timing.
That is dependent upon a few things being correct though.


First, 304 stainless fittings from the hardware store. There's a blanking plug on the left, screw in a fitting with a hose barb for vacuum gauge. Without a reducer the gauge will wobble but it's still usable.


First, look around the back of the carburetor. A is the idle speed screw. That being set correctly is fully dependent on the throttle linkage being set correctly-the manual goes into adequate detail on how to do that. You can see if the throttle sits on this stop or not- and that's only pushed back by the linkage rods, the carburetor does not have a spring of its' own.
B is the identification showing the carburetor model.
A must be almost fully closed at idle, no running on the main jets. Loosening it off totally you can feel where the butterfly contacts the body of the venturi. Mine is about 1 1/2 turns off that stop.


Front side, the two idle mixture screws (A) for each venturi. These need to be set for maximum manifold vacuum while setting the throttle stop for 375RPM hot idle in gear (Hydra-Matic, 400 for manual gears). It is important the fast idle mechanism is not engaged (engine up to operating temperature).
B is the vacuum advance tube you mentioned. If the throttle stop is set correctly, the vacuum to the tube is disconnected inside the carburetor and it's left at atmospheric pressure.
You can see with a timing light if the timing snaps forward when set to idle if you want to be certain.


Finally the distributor. This assumes the points are correctly gapped, A is the shaft clamp, B is the greaser, C is a 1/2" bolt that clamps the whole lot and allows about +- 15° adjustment as shown by the pointer D.

The idea is you set the pointer D to zero, clamp C down, undo A and set the timing to 10° BTDC and then tighten A.
You then have a zero datum which you can loosen C on the road and adjust in or out the timing from that datum to suit fuel, weather etc. and never lose where 10° BTDC is.

What I have found is generally adequate is to set D to zero, loosen A, idle the engine and twist the dizzy for highest engine speed without it stuttering, then tighten it up again, then use C to tweak the timing on the road if it needs.

With 90 octane non-ethanol gasoline that is about 17-19° BTDC at idle on this engine.

Phil

 

Hi Phil,
Thanks for the great write up on how to set the timing with the pictures and identification letters. I appreciate the the time you took to do this. My car is in winter storage now but as I recall my set up is the same or very similar to yours. My Chieftain runs so good I haven’t given it a tune up. I have had it since 2017 and I think it should get one this year. The spark plugs look like they have been there since the 50’s. I did get a complete tune up kit with the car when I bought it, but the boxes looks like they are also very old. I will print your instructions and use them in April or May when I do the tune up and let you know how it goes.
Thanks again for your help,
Greg

 

Well, usefully the cam is very soft and the compression ratio is low, so the tuning doesn't come to a real peak like you get on the later hi-po engines.
It's more of a gentle curve, so if you're in the right ball-park it can be quite difficult to find the absolute top spot but as with a lot of these older low-revving engines, if you're got it within about 5 degrees it's real happy. the main difference is running temperature in traffic and fuel economy within those 5 degrees of adjustment.

 

Right now it cranks slow when it has been sitting 5-15 minutes after driving. I had the starter rebuilt by a starter shop and had them make me new battery cables that look like they belong on an electric fork truck. It always starts but it cranks so slow it makes me nervous. I hope maybe timing adjustment will improve this.
Cast into my head it says “high compression”. Back then I think that meant 8:1 instead of 7:1

 

High compression is 6.5:1 instead of 6:1!
Those 6V starters always sound lazy. Ignore mine when you hear it because it's a 6V motor with a 12V solenoid; that makes it rather more enthusiastic...
Unless it's well before 10 degrees the timing won't make much difference to how it sounds when cranking over. You do well with the big cables- I have 00 gauge welding wire for my battery cable, but the battery is in the trunk, so the additional cross-section is needed to cover that distance.
Sounds like it's been nice and reliable, which is a good thing!

--Phil

 

Yes, it has been very reliable since we discovered the master brake cylinder rod washer was on backwards from previous owner. (After 15 brake application the brakes would not go off.) Also, it’s been much better since we moved electric fuel pump near gas tank and not next to exhaust manifold. The previous owner was a really nice guy and gave us a really good deal but his auto mechanic skills......
After I finish my 32 3 window next on the list is a ton of work on the Chieftain. A complete brand new wiring harness set came with the car that I want to install and I would like to final wet sand the paint and fix a few little things just like you are doing which is why I love this thread!!!

 

I got the itch to fix something tonight, so I went out to the garage and pulled the screen wash pickle jar out of the car and disassembled it.


Last time I went to use the thing it didn't work! That was irritating, so I decided to investigate.


I tried to get the main seal to work a bit better but it was nice and pliable from the last time I took it apart and rubbed it down with a little brake cleaner. With my finger over the intake tube it was hissing and I could pull it out against only moderate resistance. Took the top off and looked at the top seal- it had totally perished.


I cut a new seal from the only thing I had that fit- the end of the nozzle of my blow gun. I cut it off, sanded it flat and buffed it smooth. Located on there, trying to move the piston caused the seal to grab correctly and prevent movement. Better.
That pin moves, and it's designed to leak when it's pressed, and forms part of the auto-repeat.
When you open the vacuum valve, the piston is drawn up against the main spring. There's a shutter valve held open by a light spring, which is pushed shut, cancels the vacuum and opens that rubber bung to let air in, the piston drops a short way, the rubber bung seals as the shutter valve opens and the vacuum is back on.. repeat staccato. So, if you hold the vacuum on it should pump all the time you do.


Acid test- correctly functioning screen wash. Much better. I'll have to check and see if the repeating action works, I forgot to and it's too late to go check again now.

Múy bien.

Phil

 

Well, the auto-repeat function doesn't work but if you twist the knob and let go, the screen wash now sprays onto the screen for a couple seconds as it compresses then releases the spring so that's good enough for me.

 

Horses be held.

It's not auto repeat.

I just thought about what it's doing. If you hold the vacuum on, it draws the piston up. The peg on the bottom pushes against the plate, which does two things- one, it opens the chamber to atmosphere, two it pushes over the vacuum port and the spring under that plate is weak and will not push back off if the vacuum is held.

The action is to draw up, close off vacuum and open to atmosphere and just let the screen wash spray one time.

Which it does.

Ok, so it's working properly now. No need for me to mess with it any more. Huzzah.
I do need to get new screen wash because I've almost used it all up testing...

Phil