VCCA Home Forums TECHNICAL - 1945 AND EARLIER 1933-1936 enough spark? 36

Last fall I got some good advice from you guys about starting my rebuilt engine (36 Master). Got distracted with some other repairs, and now I'm back at it. With some Marvel mystery oil in the cylinders, I took out the plugs, and with a 12V battery, it turned over very fast. Having loosened everything up, I put the plugs back in and it turns over well enough that it should be starting. But it's not firing at all. I checked spark at the plugs, and there is a spark, but I'm not sure if it is enough. I'm used to the bright blue spark in newer cars, but how do I know I've got enough? Any simple way to reliably test the coil?

I'm relatively certain I'm getting gas into the carburetor, and I primed it with a small amount of gas.

I would appreciate it if you could point me in the right direction.

Are you checking the spark at the end of the grounded spark plug wire or grounded plug? Weak spark can be caused by a weak coil, bad points,a leaking condenser or bad spark plug wires. Are you sure you have It timed properly? Is the gas fresh? Try turning It over on 12 volts and see If It fires.
Richard

I agree with P.U. Guy.

Also, check to see if the valves are adjusted properly. After having my 30 motor rebuilt, I couldn't get it to fire either. Turns out I had the valves misadjusted and was not getting much compression. For the coil, the 30 owners manual says;
"In order to determine if the coil is operating properly, secure a piece of wire, attach one end on the frame of car or motor casting or other metallic "ground", bring the other end to within 3/16" from the point where the high tension wire (running from coil to the central terminal on the distributor) leads from the coil and crank the motor by hand with the switch on. If a spark occurs at this point, the coil is operating properly."
Although this is for the 1930, the method should work for the 36 also.

Good luck,

Dan

Spark plugs, distributor, cap, rotor, condensor, spark plug wires all new. The only thing I haven't changed is the coil.

I checked the spark with the spark plug attached and body of the plug grounded. Seemed like a weak spark to me, but I'm not quite sure how to judge this. Checked the coil the way the manual you quoted suggested, but even if there's a spark, I'm concerned that the coil could be weak.

I'm going to double-check the timing and valve adjustments tomorrow.

Are you sure that the case on the condenser is grounded? If not you are likely to get a weak spark. Making sure of grounds is critical in these old Chevys.

Will check this. Thanks Chipper.

Take an old (or new) spark plug of any kind and increase the gap to about 70 or 80 thousands. Ground the side of the plug to a good ground (any place on the engine) and attach the plug wire and then test the spark. If its healthy it sould jump the gap.

Great idea, Gene. I'll let you know what happens.

The spark jumped the gap just fine at 80 thousand. That's one possibility eliminated. Will proceed to double-check timing.

If it were mine I would jump it with a 12 volt booster pack or 12 V battery to get it going. But do recheck the "other things" first.

Yes, I'm using a 12volt battery and a charger in start mode.

Probably unrelated, but should I be getting oil pumped up to the valves/rocker arms when just the starter is operating? Or does the engine actually have to be running?

Oh, well. Two steps back... While checking the timing, etc., I heard a sizzling sound, and smelled something burning. I left the 12 volt battery connected with the ignition switch on a bit too long, and it looks like I burned up the coil. Bad move. Live and learn. At least they're not very expensive.
Will update after getting a new coil from the Filling Station.

Fortunately, it looks like the coil still works, but I've ordered a new one just to have it on hand. Valves have been re-adjusted, but I think they were set ok to begin with.

My 12 volt battery and an 80amp starter/charger in start mode turns it fast with the plugs out, but still slow with them in. When I try again, I thought about also getting a compatible 12 volt starter to use temporarily to get it running. Any value to doing this?

Hi Randy,

Good to hear you didn't completely fry your coil.

Have you checked compression in cylinders? No compression = no running. Also, are the spark plug wires connected correctly? Possibly 180 degrees out? That is, set to fire on number 6 when it should be firing on number 1. I only suggest these things because of some embarassingly similar difficulties.

I don't know if hooking up a 12 volt starter will help. It seems that the 6 volt starter would spin the motor much faster with the 12 volt starter pack. On mine, when everything is tuned up just right and it's not too cold, it will fire up with about half a rotation of the motor.

Keep on tryin' and good luck.

Dan

Thanks, Dan. This is a freshly rebuilt engine. Compression is definitely not a problem. I believe the spark plug wires are correctly installed, as they are just like they were in the picture I took before disassembly. Looking at the distributor from the side (passenger side), #6 (nearest the firewall) plug wire is at about 12 o'clock, and the order is 6,2,4,1,5,3 proceeding clockwise. If that isn't correct, please let me know. I've made lots of embarrassing mistakes, and expect to make lots more! As long as I learn something...

Randy,

I think you're 180 out on the firing order. Mine is set up with #1 in the 12 o'clock position and #6 in the 6 o'clock postition. I'll email you some pics of what mine look like. Of course, our distributors could be set 180 opposite each other, in which case your's is correct as it sits.

Dan

I would like to think it's that simple. But it is the same way I had it before disassembly (and running).
[img]http://www.flickr.com/photos/14907429@N00/4718572049/[/img]
This seems to be the same as the arrangement on other 36 Chevys I've seen on the web. Not sure why they're different.

Sorry, should show up this time. Click on link to Distributor.

Distributor

Right you are, Randy. If it worked that way before, it should work again. Starting to sound like a mystery wrapped in an enigma. Not to mention frustrating. These old engines are simple enough that if they don't run it is either because of no gas or no spark. Are the plugs wet at all and/or smell of gas after you've cranked on it a bit? I'll keep pondering about this one for a while. Don't give up.

Dan

One other possibility. When mine was rebuilt, the machinist recommened towing the car up to second gear speed and then easing out the clutch to get it to start. He said it would probably be too tight to start it initially with the starter motor. He was right.

Dan

There is some smell of gas, so it could be flooded. Not surprised if that's the case after so much cranking. But the plugs are still dry enough that I can get a spark with the plug out and grounded to the engine. While I wait for a new distributor, and locate a stronger charger/starter (or maybe another 12 volt battery, with 2 in parallel) so I know it's cranking fast enough, I'll give it a few days to dry out (plugs out) and try again.

Are you going to replace the distributor, or did you mean coil? Sometimes, just walking away from these for a while helps.

Good luck, you'll get her going again,

Dan

distributor is brand new, as well as condensor, rotor, cap, spark plug wires, plugs. Starter has been rebuilt. Only thing original in the ignition system is the coil.

By the way, drift starting it on a hill is not an option right now. Don't have the steering completed yet. Oh, and the transmission is not in, no seats, etc. So going down a hill could be challenging. Might have to do more of the assembly if that becomes the only option.

I agree that these engines are simple. Fuel, spark,boom! That is assuming that everything else is in line, ( timing, etc. ) While I don't do It often, I have used a starter fluid. If you shoot some in to the carb and you spin It with 12 volts, It WILL start! If It doesn't you don't have spark, compression etc.
Richard

If the disributor is 180 Deg. out it will pop back through the carburetor when turning over.
You could dump about 2 Oz. of gas down the throat of the carb.....It it dosen't try to start then you will know the lack of gas is not the problem. If that causes it to be flooded the gas will evaporate after a few hours.I assume you have the choke closed and the accelerator open about 1/3 of the way. If the starterator is working and adjusted correctly this would occur naturally.
Don't be afraid to rotate the distributor an inch or so either way for a trial.

In looking at the photo of your distributor, the firing order is correct and so is the location of the wires on the distributor cap. Number one wire should be at about 5:30 on the cap and that's where you have it.

Thanks guys. I did try a little gas in the carb, with no help. Choke is closed. No starterator, as it was converted long ago to foot-operated starter button. Will play with the distributor once I have a new coil.

Will also try the starting fluid. PU Guy, thanks for the tip.

Everything I have seen posted is correct. I would still suggest
making sure the distributor is not 180 deg off this is a very
simple test. with the valve cover removed, slowly turn the
engine over and watch No.6 exhaust valve (The last valve in the
head) continue turning engine till No 6 exh valve opens and
then closes. When the valve just closes ant the intake valve
just begins to open No. 1 cyl is in top dead center compression
position, and the timing mark ball should be visible. remove
the dist cap, and the rotor should be directly under where No.1
wire is. The dist points should be just be at the point of braking when the dist shaft is turned clockwise. If these conditions are met, the engine is in time! Phil Lipton

Randy,
From the photo it appears the distributor is installed correctly and not 180 degrees off. The number 1 plug lead is approximately correct and since the distributor cap is keyed and can only go on the distributor one way.
I just compared my distributor position to yours in the photo and (with about 8 degrees of advance) my #1 distributor lead is about at the 5 o'clock position (or a hair earlier) and yours is closer to 5:30 or a bit later. Not a big difference but it might help. Bump up your advance and then you can fine tune it when it's running.

Thanks. Taking a day off tomorrow to work on this. Will check to see if timing mark is visible when No. 1 cylinder is at top dead center. If not, what is the remedy? Would that mean that the timing gears are not aligned? That's one thing that I had the machine shop do, and assumed it was correct.

Regarding the advance, I am starting at 0, per the manual. Probably won't make a lot of difference yet, but will advance a bit.

When the timing mark is in the center of the hole, #1 intake and exhaust valves must both be closed and the rotor pointing at the #1 spark plug (wire) terminal of the dist. cap.

I am not trying to hijack this thread, but It reminded me of something. I have some old (1936) spec sheets that show a Koilster reading, hot and cold, for a good coil. Does anyone know what these readings are or how to take them? Cold is 42-64, hot is 36-56. Seems too high to be ohm readings.
Richard

I am not sure but I believe that a Koilster may have something to do with setting an German aviation altimeter.....






just kidding that would be a
Kollsman window reading

Just guessing, but aren't those typical readings in ohms for secondary windings?

What's that saying? Houston, we have a problem. Sorry I'm a little slow with this guys, but it does appear that the timing is way off.

Per Phil's suggestion, I turned the engine by hand until the #6 exhaust valve opened and then closed. Continued to turn a little, and when the #6 intake valve just began to open, I verified that #1 cylinder was at TDC (straw in spark plug hole). At this point the timing mark was NOT visible, and the rotor pointed about to spark plug wire #4. I had to turn the crank about another 3/4 turn before the timing mark was visible.

Per Gene's suggestion, with timing mark visible, #1 exh valve is still slightly open. It closed in another 1/4 turn.

So at least I know what the problem is. Now, how do I correct it? I'm not sure if I want to know the answer, but I'll bet it involves pulling the harmonic balancer, timing cover and timing gears. As I said, this is one task I left to the machine shop, thinking they won't get it wrong. Live and learn...

I guess there is a lot of truth to the saying: "If you want a job done right, do It yourself". Well, as you said now you know what the problem Is. The only solution Is to re-time the cam correctly. There should be marks on the crank and cam gears to align. Yes, the front pulley and camshaft cover must be pulled. What takes the time Is taking off everything up front to get to the balancer.
Richard

If the machine shop did screw up the valve timing, then I would say they are not much of a machine shop.

I agree with The Dog. I might be a little concerned with their other work as well.
Richard

You may be right about the shop, but now I just have to deal with it. I'm certain I looked to see if the timing marks on the gears were aligned with one another. Is there any way that the gears could be aligned to each other and not be timed properly? Any instructions on how to proceed would be appreciated.

I remember that the balancer was a bear to get off. That's why I had the shop do it. It now has a new balancer, recently installed. Any advice how how to get it off?

The good part is that the body is still not completely assembled. No bumpers, no fenders. It will be relatively easy to pull the radiator and shroud back off and get to the front of the engine. Just want to make sure I do this right this time.

Absolutely! If they couldn't get a simple thing like the valve timing correct, then there is a good chance that there could be other issues with the engine as well...especially with the babbitt bearings and etc.

I would have the machine shop correct the problem since you paid them to do the engine, or you should get a partial refund if you have to fix the problem yourself.

If you feel that the timing gears are correct, there is one other thing to try to verify the timing: Remove all of the plugs and crank the engine over by hand. With your thumb on the number one spark plug hole when the compression blows your thumb off of the hole, move the crank just slightly until the pointer lines up with the timing mark. If there is no timing mark, go around again and do the same procedure. Once there, remove the distributor cap and check the position of the rotor. If the rotor is pointing to any cylinder other than number one, then you probably have the distributor out of time.

Just talked to the machine shop mechanic who did the work. He's offered to come to my house and check the timing. Very decent of him, I have to say. Will let you know what we find.

I would do that before tearing the front of the engine down. Hopefully it is just a matter of the distributor being out of time and not the valve train.

It's possible that the camshaft gear is mis-marked. I ran
into that with an after market gear. If you suspect that to
be the case, get another gear and compare the position of the timing mark relative to the keyway where the gear goes
on the camshaft. If they are different you found the problem.
When No 6 exh closes and No 1 valves are both closed the
timing ball should be visible and the crank in TDC compression. I can't believe the flywheel was not installed
correctly, I believe the bolt pattern will only align 1 way.
I am anxiously awaiting the results!

Joe
I am not sure how many positions the flywheel will fit but it maybe possible the flywheel is 1/4 turn off position on the crankshaft as you state with #6 valves rocking #1 piston at TDC so I doubt the cam timing is out.

It is also the possible the distributor is positioned incorrectly, with the oil pump driving off the base positioning the distributor can be tricky.

Tony

Tony,
I think you are right on! Phil's comments about a mismarked gear had me worried, but my mechanic came over last evening, and verified that our cam/crank alignment looked fine, and the valves were opening and closing as they should. Clearly, it's easier to do this more accurately with 2 people, especially one who knows more than me. I located my old compression tester and can verify the compression stroke TDC by myself now. Bottom line: at TDC on the compression stroke of cylinder #1, the timing mark on the flywheel is aligned.

HOWEVER, the distributor rotor was pointed at about spark plug wire #4. I thought the distributor only went in one way, but my mechanic showed me that it can slide in to mesh with the gear in an unpredictable way. It took a little trial and error, but we finally got it aligned so that at TDC on #1, the rotor points to #1. I don't know if it makes it any more difficult, but I "upgraded" the oil pump to a gear-driven type when I rebuilt the engine.

Engine actually turns over a bit more easily now, but so far no start. I suspect that I damaged the coil leaving it on the 12V battery for too long, and have a new one coming from the Filling Station this week. Hopefully, I can get the cap off the old one. I've read that this can be a bit frustrating. Further update when the coil is installed.

I doubt that the kind of oil pump could be the problem, as long as it pumps oil. do you have oil pressure showing when the engine is cranking? Did you pre oil the engine by turning the oil pump with a screwdriver blade in an electric drill, before you installed the distributor?

Randy, I have run into this and simply placed the sparkplug wire for #1 in the hole where the rotor was pointing to and then continued putting the wires (according to the fireing order) around the cap, this will give you a "quick fix" and allow you to get the car running without having to pull the distributor. Just FYI.
Now did you test the ignition for a spark? by clamping an extra spark plug to a bare spot on the engine with some vice grip pliers or a CEE clamp and observe the end of the sparkplug for a spark (gaped to 40 thousandths) while cranking the starter WITH THE KEY ON? to see if there was a good hot blue spark?
Charge the battery to full charge while you are waiting on parts!

Mr. Mack, There's a spark, but a pretty wimpy one. Definitely not blue. While waiting for a new coil, I have a new 12v battery with 890 cranking amps on slow charge. I think I'm close.

Regarding the oil pump, no I'm not concerned that there's any problem with that. I did pre-oil the engine as you said, and also put some cam lube (a thicker grease) on the cam lobes.

With the flywheel being out of position will not affect how the engine runs but you wont be able to use a timing light to set the timing, just use your good ear.
Tony

When I was in auto shop 60+ years ago, we had to install a
distributor, time the engine with No1 at TDC, make sure the
rotor was in the correct position relative to No 1 wire. We
had a test engine on a stand that the instructor had bugged.
If everything was correct, and the distributor was positioned
with the points closed but at the point of breaking just as the
rotor was turned clockwise, the engine was in time. In order
to pass the course one of us had to hand crank the engine. We
did have a few sore arms, but I was the designated cramker and our engine started! I guess I learned, I remember it today like it was yesterday! Good luck, Phil

Jo, are you going to use a 12 volt system with this car? without a resistor to drop the 12 volts to 6 volts at the coil won't you be putting a strain on the coil and distributor? Why not use the 6 volt system with a good strong 6 volt battery? Have you disconnected the dash instruments (fuel gage) when you are using the 12 volt battery? Just curious......

Mr. Mack, we had a long discussion here about starting a freshly rebuilt engine. I have a new, strong 6v battery, and it barely turns it over unless the plugs are out. That's with an overhauled starter also. According to most advisers on the site, a 12 volt battery is the way to go, as long as you don't leave it on too long, disconnecting it after it starts. Some have said that they used 2 12 volt batteries to start it. In my case, I'm using a new, 890 cranking amp 12 volt battery with a starter/charger that provides another 80amps in start mode.

Since I'm still in reassembly, I still don't have all the gauges attached, just the ammeter, and no lights. I don't think it matters much with the starter, but from experience, I can tell you that the ignition coil can be damaged. While trying to get the valve timing set, I forgot to turn the ignition key off, and I started smelling something burning. The original ignition coil was boiling out, and smoking. I think I had left it on for maybe 5 minutes. I have a new one on order, and will try again, being a bit more careful to turn off the key in between attempts to start. I haven't seen any evidence that this caused any damage to the distributor, but I think I had a weak ignition coil to begin with.

Once the engine is broken in, I'm assuming that the 6v battery will work just fine.

I have used 12 volts many times to start an engine with 6 volts without any ill effects. You may have cooked the coil,
but more likely you only burnt the points. What I usually
try to do is put 12 volts to the starter only and try to
isolate the ign system to only 6 volts. Another way to do it
is once the engine is cranking on 12 volts turn on the ign
and remove the 12 volts as soon as the engine fires. I have
seen burnt points much more often than burnt out coils. Check
the point contact surfaces for burning or discoloration. Phil

Thanks, Phil. Making progress... Now that I have a new ignition coil, I isolated the coil from the 12 volt battery as you suggested. Just the 6 volt on the ignition switch and coil. That allowed me to use the heavy cable from the battery to the starter for the 12volt battery, and man, what a difference. I think my jumper cables were just too small to deliver the amps needed. It now turns over VERY fast, and I now have a nice blue spark at the plug. But, still no BANG.

I'm now looking at the carb to see if that may be contributing to the problem. I rebuilt it during the disassembly, so it's possible something may be wrong with it. Fuel pump is shooting lots of gas to the carb. Could it possibly just be old gas? I filled the tank last year, and it has been sitting since then. But I thought it would at least be good enough to get it started. Tried shooting some starter fluid down the throat of the carb, but it didn't do any good. Plugs look too dry for all the starting attempts.

From my experiance the gas should still be OK. If it dosen't "pop" with the starting fluid it is not the fuel supply or the carburetor.
I would still suggest moving the distributor around a bit - with out removing it.

Now that you have good spark, and the distributor is positioned to fire No 1 when crank is at TDC it should start.My next step would be to make sure the valves are not
set too tight. A compression test will answer that, compression should be 100 to 120 PSI, and if that's OK check
the spark plugs to make sure they aren't fouled. Between all that cranking
and gasoline and starting fluid they could be fouled. If you don't have a
spark plug cleaner another way to clean them is to place the plugs in a heat
proof metal receptical (vice) with the electrodes facing up and apply heat
with a propane (Berns-omatic) torch till the center porcelain tip is glowing
hot. Allow adequate time for them to cool down, regap, and install. The
engine should now either start or at least give pop. I strongly recommend
having a fire extinguisher nearby when cranking the engine. usually a good
timing light will help you get the dist in the proper position. You may find
it easier to do if you have a helper! Good luck, Phil Shoot me an e-mail
if you feel you need more help, or I can give you my cell No. millnphil@yahoo.com

Remember when you squirt the starting fluid down the carb, give it a good squirt....the choke needs to be open (off) and the throttle needs to be open. With the choke off and throttle open squirt the starting fluid down into the carb, pull out the choke and give the footfeed a couple of pumps, key on and CRANK with the starter. As soon as the engine starts ,or if it don't start open the choke and try it again. If the engine fails to start then, check for an obstruction in the intake, valve adjustment and obstruction in the exhaust. If you have frosted the sparkplugs or soaked them by flooding the engine, try cranking it with the footfeed peddle to the metal to get the engine unflooded. But you probably already know all this stuff......

Thanks, guys. I tested the compression with plugs out, and it's about 100 on each cylinder. I decided to make sure about the timing marks before going any further. A little extra work to pull the radiator and harmonic balancer to get the timing cover off, but worth it for peace of mind. The marks are aligned, as you can see in the photo. Click on "timing marks".

Timing marks

However, I discovered another problem that was not the fault of the shop. I drained the oil, and found lots of coolant in it. I was proceeding to disassemble enough so I could take the head off to check for a leaky head gasket, and found that the brass fitting for the oil line that goes through the block was leaking coolant. I replaced the line myself, so not the fault of the shop. It leaks at the point where it exits the block near the push rods. It apparently was draining down into the pan from here for a while, as there was some corrosion at the bottom of the push rod cover and gasket. Tightening the fitting didn't fix it, so I used some Permatex teflon cement on the threads, and retightened. Will fill it with coolant tomorrow after it dries. In retrospect, maybe I'm lucky it hasn't started yet.

Phil, if I'm still stuck after all is back together, I may send you an email and get your phone number. I appreciate the offer.

Randy, did you correct the problems and get It started? Please give us an update.
Richard

Richard,
Had to leave town for the 4th of July weekend. Will get back on this next week. I pulled out the copper oil line through the block, and will temporarily just plug both ends until I verify if there are any other coolant leaks. I'd like to avoid pulling the head if I can.

Finally got it to fire! After fixing the coolant leak problems, I put everything back together. 12 volt battery on the starter only, 6 volt battery on the ignition switch/coil. A little starting fluid and gas in the carb throat. She started right up! It's running kind of rough with some backfiring, so I think I just need to adjust the timing a bit. But getting it going again made my day. I have some smoke coming out of the vents of the valve cover. I assume that's from backfiring?

"smoke" from the valve cover vents would be normal for several reasons.
Just rotate the distributor around and find the spot where it runs the best.
Running rough - I would reset (or at least check) the valve clearences with the engine running.
Back-firing could be the timing way off or intake valves not closing because they are adjusted too tight.

Thanks Gene. Just set the timing with a timing light, and #1 is right on the timing mark. Running much smoother at low idle, but still with a little backfire every 10-20 sec. Will re-adjust valves.

While it idles ok now, when I throttle it past about 1/3, it starts running rough and dies out. Sound like carb problem?

Making progress!

Did you check the accelerator pump in your carburetor to make sure it is working when you depress the gas pedal?

I was just reading about that in the Chevy Six book. It's on the agenda for tomorrow. I installed a new carb kit in it after disassembly of the car, but haven't checked this after putting the carb back on. What do I look for? Do I just take off off the cover and see that the plunger moves as I depress the pedal?

Nope! With the air cleaner off, look down the air horn of the carburetor and pull up on the throttle linkage. You should see some gas squirt into the venturi of the carburetor.

Thanks a bunch guys! Gene, you were right on with the valve adjustment. Since I had the engine up to temperature, I went back and tightened the cylinder head bolts (still ok) and rocker arm assembly bolts (loose!). Then readjusted valve clearances cold. I left them a little loose for now (.010 intake, .015 exhaust). It's running like a top! This also fixed the acceleration problem, and there's just some minor backfiring when I rev the engine. I'll readjust the valves hot later.

I'm pretty excited about this, and can't thank you guys enough. I'm going to have to make a short video, and post.

Video of start up:
Video link

Fired right up! Way to go Randy.

Dan

Congrats Randy! Another Chevy is ready to hit the road!

You might want to go back and read Chev Nut's post and take a look at the timing. If you have it set right on the timing mark it may run but try advancing the timing (loosen the octane selector and twist the distributor) until it smooths out. The original setting was for gas that had much lower octane than today's fuel, so 6 to 8 degrees of advance can be used to make her run even smoother...and may help with the backfiring issue.

One more thought. The more I use my car the better she runs. So drive it like you stole it and enjoy it!

Good job Randy! I'll bet It is a real relief hearing It run.
Richard