Technical 1950 Flathead 8BA Inital start trouble shoot

Not a flathead expert but I think you have enough compression that it should start, at least sputter and pop. You mentioned new rings on a honed cylinder, the engine hasn't even fired yet so the rings haven't seated yet as proven by the fact you added oil to the cylinders and the compression improved. Valves would not show improvement by adding oil. This might sound dumb but are the plugs gas fouled to where they won't fire? you stated you have spark to the end of the wire but the plug inside the cylinder might not actually be firing when wet. Also, Pertronix modules need a full 12 volts to work correctly. I have seen the power wire to the pertronix hooked up AFTER the ballast resistor and not fire at the correct time due to the low voltage. It needs a full 12 volts to fire when triggered.

 

Fixed it to read sensor. I'm getting an education on Pertronix ign this morning while hunting for an answer for you.
I may need that as I am pretty sure the previous owner installed one on my Bayliner 2450

Trouble shooting is still a process of elimination.
That you seem to be doing by checking things.
Cam is in time with the crank =checked.
spark to the plug = Checked
Compression= Checked and it should have enough to fire up. I've seen engine run with a lot less even though they didn't run well. Compression is reasonably even meaning you don't have a valve issue.

That brings us back to timing and fuel delivery.
If the spark plugs aren't gas soaked and are gapped correctly they should fire. It's not logical that you would get a box of eight bad or suspect spark plugs. That said, one of those old Champion spark plug testers that every garage used to have back in the day sure would be nice right now to eliminate that.

Make sure that you have the timing correct by bring number 1 up on TDC lining up the mark with your pointer and lining up the rotor with number one terminal on the cap.

Then I would use something to fill the float bowls though the vent tube in the air horn (s) and try again. I say fill the float bowls as I am not a big fan of cranking an engine over trying to pump fuel to dry float bowls. Then go for it.

 

One more thing you might want to check; I've had this happen to me more than a couple of times. Check to make sure you have a nice strong bluish spark that really snaps. An anemic weak yellow - orange spark might not be enough to fire the cylinders. A poor coil can produce spark but not enough to light up the engine.

 

Valves being open during compression equals low or no compression. If the valve lash is too tight the valve is hanging open causing low compression.


Sent from my iPad using The H.A.M.B. mobile app

 

Appreciate all the help! Spark is BLUE
New 12V harness installed for complete car
Power Master starter and Power Master generator
Which is an really an Alternator
These are the best $600 with tax between the two
12 volt system and new battery that I charge between intervals
Starter is strong and fast
I am going to convert to adjustable lifters and a new intake
Between the two I think I will have exhausted the issues
Yesterday Sprayed ether and poured fuel down the hatch again today and still the plugs did not smell strong of gas or ether as they should nor did they appear wet . I think that hokey carb set up is bogus and maybe my 94 rebuilds suck although they are squirting???
It’s almost like there is a blockage which is why I am going after the induction set up

 

question regarding distributor vacuum advance. currently one of the 94 carbs has the vacuum port built in. If i switch to a different 94 without can i run the vacuum advance line to an aluminum spacer between the 94 and the manifold? Will it work there?

 

A brand new Model A motor has less compression than your readings and they run fine. I would try a new set of spark plugs. Sounds like you've dumped a lot of stuff into the cylinders and they may just be bleeding your spark off.

 

If there is a big vacuum leak somewhere it will suck in air somewhere other than the carbs, when the piston goes down air will flow through the path of least resistance. That could explain why fuel is not being drawn in from the carbs. My opinion is that the valves are working or you wouldn't have any compression and the compression you have would not improve when you added oil to the cylinder. Just my two cents.

 

A plugged exhaust pipe or muffler will also prevent any fuel charge from entering cylinders


Sent from my iPhone using H.A.M.B.

 

Using lake headers and no mufflers or baffels open to the side so no obstruction there.

 

Remove the intake and you should be able to see if the valves are moving correctly.
Also,,,,you can mist some fuel in the intake ports,,,if it doesn’t at least blubber a little and fire some,,,,,then it’s not your fuel issue .
I don’t know about getting your plugs wet,,,,,but they might still not fire in the cylinder?
You could even try removing a plug and leaving the wire attached,,,,it should spark a little,, if it is any good at all .

Tommy

 

I doubt it would work.
Go back to square one.
Remove your dual carb intake and install a single carb intake. Get a good Venturi 94 carb and start from there.

 

Aright you ready for some wild shit diagnosis ? Took off both carbs and locked down the the single best one that had the advance port. Sprayed ether, pumped gas in and poured a little. ....Nothing and sounded slower that usual.
Decided to pull all plugs and do an inspection all plugs looked dry again . Cycled the engine with plugs out and fluid flew out of 1 and 5 . I mean ALOT ... like A GYSER a pool had been sitting there in 1 and 5 . did it about three times before it stopped. Did catch on fire in the front two plug holes on both sides i assume from vapor and spark inside the wires that were left open lying about Anyway after that was clear the engine sped up dramatically. I finally was able to look down the plug holes after i flushed my face with water, yes i got a facefull. and did notice that all the valves are moving up and down as they should. So i have lake headers which are very close to the frame and to compensate i added two 1/2 inch nuts to the trans mount to get clearance so the headers did not lay on the frame rails. Did this quite a while back and to boot i had the ass end of the car 2 or 3 inches off the ground. I run big and little so it takes even a bit more to get them up. My theory is that because of an engine that is at an angle not conducive for level fuel flow all the gas and ether had run to the front drowning #1 and #5 and not allowing any fuel to the other 6 holes in the back. Even though though 1 and 5 looked dry.???While this was going on it hydrolocked (not totally) the engine slowing it down. What do you think? Based on this i will attempt to get engine back to proper degree angle. ???? Sound like a decent theory?
Such is hot rodding! .

 

Might want to check the oil and see if it's dilluted. Looks like it's a case of not firing and and continually adding gas and ether. Washed the cyl walls down, hence low compression. I would dry her out, fresh plugs and give her a couple squirts of gas and try it. No response? Stop and troubleshoot more. JMO Lippy

 

Now that it’s cleared out.
I’d again suggest a simple approach of a single carb and intake.
Get it running correctly then make your changes one item at a time.

 

I know this sounds silly,,,,,but the inside of the intake is clear,,,,isn’t it ?
Could there have been a rag or something shoved inside while off for the refurbishment,,,,and forgotten ?
Usually when an unexplained condition occurs,,,,,,there is an unusual circumstance that is present !
This engine should fire !
Go back to basics ,,,,101 .
Like the man said,,,,,check the compression.
On all 8 ,,,,if the compression is good,,,,,move on to fuel,,,,then the fire .
All that is left after that is timing .

And if it don’t fire on ether,,,,,,something is definitely wrong .
Ether uses compression only to ignite.
It was designed to fire at 2 to 1 compression!

And ether evaporates very fast,,,,,it was gone before you got blasted in the face with the fuel.
It is unusual that only fuel was in the two front cylinders,,,,I think .

Tommy

 

Greetings Bustingear!!... you ask how the valve clearance/lash could be wrong...when you lap,the seats the head of the valve sinks lower in the block closing up the lash...but it should run on 75-80 psi compression. Also the 8BA style distributor has vacuum advance only so the vacuum hose needs to go to ported vacuum....that means on the carburetor above the throttle blades....NOW, if you have fuel and squeeze it some and light it anywhere near the proper time you ought to get at least a few farts and sputtering...it seems that something is seriously out of time...I would take the intake manifold off, remove the spark plugs and be sure you know which cylnder is #1 then turn the crank with a ratchet watching the valves and timing mark on the front pulley....make sue the intake valve closes almost half a crankshaft revolution before the timing marks line up verifying the valve timing is close to correct. If that appears correct squirt a little gas down each intake port , turn on ignition and while cranking and attempting to get a few cylinders to fire turn the distributor body in either direction A BUNCH thus at least semi eliminating ignition timing as the issue...

 

I dont understand how it could be out of time when you take the timing cover off and make sure the cam gear slash and the crank gear dot meet at 6 and 12 oclock. Put the timing cover back on and the needle and the pully Dot meet dead on as well as well. Then you pull the cap and the rotor is pointing directly at the #1 plug wire and then you check the order of the wires 5 times and they are correct to the firing order on the cap and meet the correct plug holes. And then you pull a #1 plug and rotate the engine till you see spark on the plug end and stop immediately and pull the cap again and the rotor is on #1 plug wire again. I ask then how could it be out of time? What then am i missing?

 

Are these the same timing gears from before the refurb ?
If it’s all lined up and the dots match,,,it should be right,,,,,,but it’s a possibility that a new gear could have been endexed wrong and the dot misplaced ?

Tommy

 

there was a thread on the barn similar a while back, and it was found that the crank gear was on backwards, and the mark used to time it was just some scratch or ding.

 

I'm guessing a rag in the intake.

 

It would have eaten a rag by now.


Sent from my iPad using The H.A.M.B. mobile app

 

Hey bustingear any updates? Pete

 

If the cam was that far off from where it should be there wouldn't be any compression to speak of. I think the compression readings would rule out the cam/crank being too far out. Even if it was one tooth off either way it should still run or pop out the carb or exhaust. The fact that there is NOTHING that would indicate the fuel was being lit by the plugs, no backfires, no pop back through the carb makes me suspicious it is not firing the plugs in the cylinder for some reason. Yes, I understand there is a good spark outside the cylinder but under pressure the plug might not light or something is wrong with the fuel.

 

Not being familiar with 8BAs, is there a timing mark? Or is it all done by feel? If there’s a mark you could put your light on #1 and see if things are close as the engine is being spun over.
BTW I’ve only had two FH v8s , and the 239 I had ran like a top with 100-105 compression, the 221 I had was 85-90 and ran near as well.

 

Autoignition temperature of diethyl ether is 320ºF. If you begin with air at 70º it takes a little bit more than a 2 to 1 compression ratio. Autoignition would occur at just under a 3 to 1 compression ratio, assuming adiabatic compression where none of the heat of compression is transferred to the surrounding piston, head or cylinder wall.

I apologize for my geekiness. Science fascinates me.

 

I think “nerd” is more like it

 

Better a nerd than a turd.

My apologies to the Turds car club. You know what I mean.

 

Points and Condenser set at 17, and a different coil, sometimes a coil will put out a little spark but not enough to start, also check all the wiring inside the distributor hot and ground above and below the point plate.

 

I didn't see the dots on the timing and crank gears in the picture you posted? The gears I have both have a dot on them as in the pics below.