aristech

1936 Pontiac 8ba 6-volt battery

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I have a few questions first does anyone know the correct replacement 6-volt battery. Next question is the battery positive ground or negative ground? I pulled a battery from one of my chevrolet six's and thought I would be able to get away with using the battery I already have but seems like it is cranking really slow. I understand that yes 6-volts crank slower than 12-volt but in my opinion it is just way to slow. I put new plugs wires,cap,rotor and points. Rebuilt carb new fuel pump and I am getting gas to carb but it just cranks and does not want to fire. 

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Benefits of AACA Membership.

A 1936 Pontiac is negative ground.

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2 hours ago, The 55er said:

A 1936 Pontiac is negative ground.

Try connecting a car starting jumper cable from the ground terminal of the battery to a head bolt, and see if the cranking speed increases.

 

Jon.

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Got Spark?

 

The eight isn't really much more displacement than the six. It isn't much more compression either. Maybe a little more mechanical drag. My 1936 six cranks like crazy.

 

Positive cable comes from the battery and goes forward (there is asphalt loom and a little steel loop to hold it to the frame. It ends at the starter.

 

Negative cable (strap) goes to the frame.

 

A third cable (strap) goes from the frame to the engine or bellhousing or something. With the drivers side hood open, you should be able to see it if you look down an back toward the firewall.

 

Make sure all are clean and tight.

 

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Update. I have cleaned the strap from engine to frame and also changed my negative cable to a new 2 gauge cable also cleaned frame. I am getting cranks faster now. Next question I have replaced the points,cap,rotor,wires and plugs. I am getting spark and fuel. The carburetor pops ever so often as I am cranking the motor. Is this possibly a points gap issue ? 

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Check your timing. Is it possible that your distributor is a tooth or two off?

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1 minute ago, Matt Harwood said:

Check your timing. Is it possible that your distributor is a tooth or two off?

 I was thinking that. When I look at the distributor it looks like it has not been pulled out at all.  Can I loosen the collar and turn the rotor slightly? 

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Posted (edited)

Or maybe 180 degrees out? It will appear to be correct, but instead of running will intermittently pop back through the carb and exhaust.

 

EDIT: Probably not if it wasn.t ever pulled.

 

Make sure the ground wire in the distributor is present, and that the hot wire from the side post to the points has no bare spots that are touching ground.

 

If there is no dwellmeter available, set the points with a feeler gauge. If there is no feeler gauge available, use a matchbook. Drag a piece of paper soaked in brake clean or alcohol through them (while closed) to clean them off after setting them.

Edited by Bloo (see edit history)
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Any one have the shop manual for the 1936 Pontiac 8 firing order? 

 

 

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with a proper size gage battery cables, the six volt starter should spin as fast, or almost as fast as a twelve volt starter does, i've seen the difference it made in a 1948 cadillac 346 L head V8.

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Posted (edited)

OK here is what I did I first used a 12 volt battery to crank the motor to UDC once I was able to see the mark on the flywheel I then re positioned the wires on the cap. Then the car fired right up. Unfortunately I think I  have a rod knock. Oil pressure shows at 40 psi. I was thinking about doing an oil change  and see what happens. Anyone have any other suggestions ? 

 

Also other thing I did for the motor to spin properly. 

I cleaned the ground that goes from the frame to the bell housing. Then I replaced the battery ground cable with a 2 gauge wire .

Edited by aristech (see edit history)

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After changing the oil . I dont think it is a spun bearing . I think it is a lifter issue. Is there any videos out there regarding the repair of the lifters in these 8 motors?  I am dreading taking the side covers off but if I have too I will so I van see which one it is .

 

 

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1 hour ago, aristech said:

After changing the oil . I dont think it is a spun bearing . I think it is a lifter issue. Is there any videos out there regarding the repair of the lifters in these 8 motors?  I am dreading taking the side covers off but if I have too I will so I van see which one it is .

 

 

the lifters are the solid type, no hydraulic, takes three wrenches and a feeler gauge to properly adjust and lock them down.

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1 minute ago, pontiac1953 said:

the lifters are the solid type, no hydraulic, takes three wrenches and a feeler gauge to properly adjust and lock them down.

Is this something that is common when a motor has been sitting for a long time and out side that the lifters could be stuck  ? 

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Posted (edited)

Take em off!

 

Gaskets are readily available. The lifters are solid. I have read of failures (even though they are not hydraulic). I am not sure what that looks like. Mine had an extremely loud one, and it was just adjustment. They are a bit of a pain to adjust. It is 3 wrenches (lifter, screw, and locknut). I did not do them running as some would advise. The exhaust pipe is hot. I adjusted the valves cold, probably at the loose end of spec, or maybe allowed .002 extra if the spec was not a range. The loud one was way over 0.030 .

 

After I adjusted them, I rechecked them with a dial indicator, and re-adjusted 2 of them slightly. They are quiet and all sound the same now. (This step is completely optional, compensates for pounding wear where the valve stem contacts the lifter.)

 

Go for it! There is probably nothing serious wrong.

 

EDIT: One more thing, If the engine has not run in years, I might just leave alone the ones that are "close" if they are a tiny bit loose. The valves that were open when it sat could have some rust or crud on them, and they might tighten with use. You don't ever want them too tight. Do the valve adjustment again after you have driven it a little while, get them more perfect on the second go around. Glue your gaskets to your side covers with shellac, so they will stay with the covers and you wont need new gaskets every time.

 

Edited by Bloo (see edit history)

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7 minutes ago, Bloo said:

Take em off!

 

Gaskets are readily available. The lifters are solid. I have read of failures (even though they are not hydraulic). I am not sure what that looks like. Mine had an extremely loud one, and it was just adjustment. I suspect They are a bit of a pain to adjust. It is 3 wrenches (lifter, screw, and locknut). I did not do them running as some would advise. The exhaust is hot. I adjusted the valves cold, probably at the loose end of spec, or maybe allowed .002 extra if the spec was not a range. The loud one was way over 0.030 .

 

After I adjusted them, I rechecked them with a dial indicator, and re-adjusted 2 of them slightly. The are quiet and all sound the same now.

 

Go for it! There is probably nothing serious wrong.

 

Cool thanks for the advice. I am gonna order the gaskets and pull the covers off. I am guessing it is best to remove the access panel on the fender also so  it is a little easier to service ?

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After reading the shop manual it says intake .009 exhaust .011  while engine is at normal operating tempreature. 

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If your straight 8 is similar to my straight 8 in my 37 Olds, I had some lifters frozen in the up position. I took off manifold and side covers and used Kriol & PB blaster and worked them loose with a wrench. After everything was free and I checked the setting they all were in specs. Mine set not running sincce 1975.

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Posted (edited)
2 hours ago, aristech said:

I am guessing it is best to remove the access panel on the fender also so  it is a little easier to service ?

 

Yes. It's still tight even with the access panel off. Be careful with those access panel screws.....

 

Edited by Bloo (see edit history)

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2 hours ago, aristech said:

After reading the shop manual it says intake .009 exhaust .011  while engine is at normal operating tempreature.

 

I might go for .010 and .012 or maybe even .011 and .013 then since you probably cant get it hot. Loose makes noise but too tight will burn a valve.

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21 hours ago, Bloo said:

 

I might go for .010 and .012 or maybe even .011 and .013 then since you probably cant get it hot. Loose makes noise but too tight will burn a valve.

when i reassembled my 1953 pontiac straight eight in 1978, i adjusted the tappet clearance to 0.012 with everything being cold at room temp. never had a burnt valve afterwards. i was so glad i adjusted the clearance with the engine on the work bench with no access problems.

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Here is a video so everyone can hear the sound.  Oil pressure stays at 40 I did and oil change and sound is still there 

 

1936 Pontiac

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Sounds like you got starter problems... Is starter mounted straight ? Maybe starter gear shaft bent... Listen under hood to pinpoint noise....sounds smooth running but clicking seems to be something else in there.... Keep us posted of your findings... John

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5 hours ago, john hess said:

Sounds like you got starter problems... Is starter mounted straight ? Maybe starter gear shaft bent... Listen under hood to pinpoint noise....sounds smooth running but clicking seems to be something else in there.... Keep us posted of your findings... John

Do you think the starter is staying in gauged? 

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