First Start-Up Woes

[Bingster]

      Well, last night my friend and I attempted to start my '47 DeSoto after ten years sitting and it was close but no go.  I had kept the piston cylinders lubed and so I could turn the engine easily by hand.  A new battery from O'Reilly's. New plug wires. New coil but about eight years old. New cap on distributor but otherwise nothing done to the insides.

 

Okay.  So we first tried to find dead center on the crankshaft pulley to line up with the arrow. After wire brushing the pulley with WD we found "DC," which I assume is dead center.

 

So with those lined up, shop manual says, "Rotate distributor shaft by means of turning engine over by hand so that the breaker point rubbing block is on a high point of cam." That means nothing to me. He told me that with the DC and pointer aligned, it had to be on the compression stroke before we attempted to fire it up. We attached the plug wires to the distributor, we followed the sequence and tried to start it. It chugged along but no firing. He tried various places on the distributor to begin the sequence and still no go. I'm wondering where the sequence on the cap begins?  It's hard to tell on diagrams because nothing is numbered on the cap. I think he may have been shooting blind. He checked the coil spark and there was one, but he said it didn't seem real strong. The manual says it has to be at least 1/4". I don't know what he considered weak. He seemed to think it was okay.

 

I thought that the engine turned over pretty well, but it didn't seem to have the "attack" that I see in videos when starting engines that have been sitting. There was no problem with the engine turning freely from the start, but the engine didn't even catch like it wanted to start.  So where was the weak spot?

 

You folks will undoubtedly decipher whether or not it makes any sense or what we might have done wrong.

 

 

 

 

 

[Sam Buchanan]

It sounds like you don't have a service manual........

[Bingster]

I do.  But I think that a service manual assumes that the mechanic knows a basic knowledge of what it talks about, and leaves out elementary info. At least that's how it seems to me because my knowledge doesn't go beyond some of the easier fixes.  And there are some photos that I would like to see in there that aren't.

[Dave72dt]

You can't assume it's on compresssion because the marker and DC line up.  It could have been 180 degrees off.    Where was the rotor pointing?  That will be either cyl 1 or cyl 6's firing point.  High points on the cam are that hexagonal piece inside the distributor.  That will open and close the points as it rotates.   YOu might want to run a point file through them and reset the gap.  What part of the state are you in?  If in the NE section, I may be close enough to help.

[Doug&Deb]

Turn the engine by hand with the plugs out and your finger on number one plug hole. Keep turning the engine until it pushes your finger off. Then check where the timing pointer is. Pull the distributor cap and see where the rotor is pointing. That will be number one cylinder. Place the rest of the wires 1 5 3 6 2 4. As for the rubbing block that’s the plastic piece on the points that contacts the hex shape under the rotor. Rotate the engine until the block is on the widest part of the hex not the flat. That’s where you adjust the points gap.

[Los_Control]

I would try a few things, first you need to clean the points. They sell a points file, or you could get by using sandpaper folded in 1/2 so it is abrasive on both sides and cleans the points top & bottom at same time.

Corrosion will build up and give you a weak spark .... when done filing the points, then you need to check or set the point gap. When you are satisfied all is good the rotae engine so points are closed. Insert a piece of white paper in between the points and pull it through to clean the dirt off the surface .... a white business card is perfect for this.

I only choose white because it is easy to see the dirt that you get off them and when it comes out clean you are done.

 

You will have to find TDC in order to set the plug wires correctly.

The proper way is to remove the pipe plug over #6 cylinder. ..... I use a tiny square of toilet paper over the hole .... it is light & fluffy 

Now when you rotate the engine by hand, coming up on compression stroke the compression will move the paper. It might blow it off the hole, or just wiggle it .... either way it is compression that made it move.

Now you want a long stiff wire to insert into the hole .... at least 8" long, you do not want to lose it in the hole.

Now rotate the engine slowly by hand until you get the wire at the very top of stroke ... when it starts to go down reverse rotation til it is back at the top.

 

Now you are on TDC compression stroke on #6 .... This means #1 is TDC on exhaust stroke. .... one more complete rotation and #6 will be on exhaust & #1 will be TDC on compression.

 

For what you are doing, just get #6 TDC on compression then remove the distributor cap and the rotor should be pointing about 1 O'clock or in that neighborhood.

If it is pointing near 7 O'clock then your distributor is installed 180 out.

 

Anyways, with #6 TDC on compression stroke, remove the cap & where the rotor is pointing that is where the #6 plug wire goes .... Then follow the firing order to install the rest of the plug wires ... just start from #6 instead of #1.

 

 

[Bingster]

Thanks for all the info. I'll digest it and go out and follow the procedures.

I do remember my friend sticking his finger into #1 but said he couldn't feel any metal as he turned the fan. I think he finally did feel compression in there.

 

He must have known where the rotor was pointing. I wasn't aware of that at the time. So I guess he knew where to begin the plug sequence.

 

I'm in Iowa near Spencer. I appreciate the offer.

[P15-D24]

Or just take the from valve cover off and turn the engine over till you see both valve close. Then go a little bit further and see if the exhaust valve is opening. Then you will know you have just got past TDC on #1.  Back it up to TDC then pull the distributor cap. The rotor should be pointing around 7 o'clock.  Pull the #1  plug wire and stick in a spare plug or neon tester light. Now you can set the timing by loosening the distributor lock bolt and just turning it so the points open and you see a flash on the tester plug/light.  That should be more than close enough to start. When you snap open the carb do you see a stream of gas going down the carb throat? 

[Los_Control]

The reason to use the pipe plug on #6, doing this particular task is exactly why it was installed on the head .... I have no idea why they did not install it on #1 cylinder though?

 

1, Our flatheads the spark plugs are over the valves and not the piston. So you can not insert a wire to watch when the piston is at TDC.

 

2, The pipe plug is smaller then the spark plug hole .... If the engine is low on compression, going through the smaller hole will concentrate the air increasing the pressure making it more noticeable.

 

3, The TDC timing marks on the pulley should be correct, for several reasons and 70+ years time passing, they are not always correct .... So mechanically setting it on TDC, now would be a good time to check the pointer on the pulley. If it is correct fine now you know. If not correct then fix it or mark it so next time it is correct.

 

One problem I ran into with my timing plug. When I tried to insert the wire it was filled with carbon.

I just took a nail and pushed the carbon plug out. Easy peasy.

When I started the engine it sounded like a ball bearing bouncing around, then it got stuck under the exhaust valve and it ran rough as heck while the valve was pounding it into the seat for about 30 seconds before it got sucked out ....... I would not do that again!

 

What I would do is use a small drill bit and drill a small pilot hole in it, then step up to bigger bits turning the carbon into a powder so it would get sucked out the exhaust without causing damage.

[Jerry Roberts]

Also , when drilling and you don't want stuff falling into the hole , put grease on your drill bit to catch most of the debris . 

[Bingster]

Thanks. I wouldn't have thought of that.

[Sniper]

You could use a shop vac to suction out the debris as you were drilling. 

[Bingster]

Pipe plug?

And by valve cover do you mean remover the head cover or the doors under the exhaust manifold?

[Doug&Deb]

The pipe plug is on the top of the cylinder head in the center above number 6 cylinder.

[Los_Control]

Here is a photo of its location with a wire inserted.

 

 

[Bingster]

I never noticed that plug there. Great!

[Bingster]

Hey, you could eat off that engine.

[Bingster]

You know, I'd love to see more pictures of that engine.

[Los_Control]

Well I never read the article, I was just doing a quick image search on google to show the plug ....

You might actually enjoy reading the article.

 

https://forums.aaca.org/topic/284782-finding-tdc-on-a-flathead-six/

[Bingster]

Thanks for the article.  That'll help a lot.

[Los_Control]

OMG please disregard that link ..... there is much confusion there.

 

 

On 11/4/2016 at 4:17 PM, Taylormade said:

Everything I can find says one o'clock for the number one cylinder to fire.  There is a detailed description of it on the P-15 D-24 web site and they say one o'clock for one and seven o'clock for six.  My wiring diagram also shows it in the one o'clock position.  If this isn't correct, my engine rebuilder did not index my oil pump correctly.

Just make sure when you put the distributor cap back on that the rotor is lined up with the spark plug wire that goes to cylinder #1. Then you know you have it right.

 

NO  NO   NO!

 

If you read the manual it is sometimes very vague .... but done properly when installing the oil pump .... #1 ends up at the 7 0'clock position on the distributor.

#6 is at the 1 O'clock position.

 

If a mechanic does not follow directions when installing the oil pump, it can be one tooth or several tooth's off. .... So we can not always rely on #7, #1 ..... My #1 is at 6 O'clock position and runs fine ..... when the mechanic installed my oil pump they were a tooth off.

 

The photo is correct in showing you the location of the timing plug ..... the rest of the thread is fud unless you can decipher the idiots from it.

[Dave72dt]

Let's start from scratch, one step at a time. Pull the plugs from 1 and six and place a piece of tissue over each plug hole.  Rotate the engine until the marks come up toward the pointer, watching the tissue paper as you do.  Which one moves?

Edited September 22, 2023 by Dave72dt

[P15-D24]

1 hour ago, Bingster said:

Pipe plug?

And by valve cover do you mean remover the head cover or the doors under the exhaust manifold?

Yes, under the exhaust manifold. 

[Ivan_B]

Are we going through all this trouble to just install the plug wires correctly? Does anyone have a picture of the 47, illustrating how its connected, they can share? It would probably either be correct or 180-degrees off, if copied ? What kind of an engine is in it? Looking-up a generic illustration on the internet might also work.

Was this engine running in the past? To feel the pressure building up with ones finger, to check when the first piston is "up", you need to rotate it somewhat quickly. Also, if you remove all the other plugs, the rotating would be easier.

[Bingster]

Mmmm, that's an interesting post.