Won`t start

Well here it is,I have a 21a it was rebuilt many years ago.I took it apart and checked it out,i did not pull any pistons because everything looked all right I did check a bearing. The Cam and valves looked good and the cylinders have a slight ridge,seemed alright to me.I put it back together a couple of months ago with aluminum heads and a dual intake,rebuilt carbs,rebuilt dist.new plugs, It is getting fuel and it is getting spark.I put marvel mystery oil in the cylinders to maybe help the comp.by loosening the rings up in case they were stuck,It does not even pop or try to start, It does turn over very slow and it has a new batt. and 00 cables,i have hit it with 12 volts does not seem to change how fast it spins to much.and the 6 volt batt seems to stay charged (it is not wearing down fast). How fast is this supposed to spin and are these autolite plugs any good? Firing order is right and it is getting plenty of fuel. Any light you can shed on this matter would be much appreciated,thanx. Pete.

 

how much compression does it have? It should have 60 or so lbs of compression in each cylinder according to the guys over on Ford Barn http://www.fordbarn.com/forum/showthread.php?t=20966 .

Engines need Fuel/air mixture, spark, and compression at the right time to run. If one of those is missing or off a bit they won't run.

Here is a link to setting a Model A distributor in case you need it.
http://www.abarnyard.com/workshop/timing.htm

 

Lay one or more plugs on the intake and spin it to check for spark at the plug. Are you gapped right? Very small gap compared to modern engines, .025 to .030
Its hard to imagine how slow the starter turns it. Try spinning it with no plugs to build up oil pressure. If all you ever heard was a 12 volt starter, a six volt would sound very slow. They worked for years that way.

 

are you trying to start this on a stand or in the car?

Turning over slow and having lower than ideal compression means it it going to be difficult to get it to start. Give a hard look at the power cables to be certain they are transferring all the power the battery can offer.

 

Sounds like your starter could be dragging and needs a tune up. Mine spins over pretty fast on 6 volts.
Could it be out of time? Should pop or something tho...

 

I don't think he is talking about a banger engine. He has a V8.

 

Try turning if over with a wrench if you can't turn it over with a wrench about a foot long I'd look inside.

 

Check timing it could be out of time

 

Take a plug out and hold the wire. Plug the hole with your thumb, crank the engine over, your thumb should pop off at the same time your eyeballs spin.

If you're a wimp. lay the plug on the block and look for the spark.

A slow starter can be caused by one of the brushed not contacting the commutator, same current draw but half the torque.

 

Wooooow it's got fire And I cat fill my hand

 

I did that once on a lawn mower to see if it was gettin spark and it shocked the piss outta me.

 

Pull plugs and check if they are fouled, clean and try some starting fluid next start.........

 

I;d like to help but I don't know what he has, what is a "21a" ??

 

The compression is low the rings are stuck going to let it sit with MMO in it for awhile let you know if that works.Thanx for all the responses.

 

Might try dosing the cylinders with 30-40W oil,the heavier oil well help seal up those rusty/stuck/ half wore out rings that you've been freeing up w/MMO. If it seals up on a comp test afterwards, try starting again, assuming you've made sure starting system is spinning engine at needed rpm.
Dave

 

Well I let it sit for a week with MMO in it,cranked it over without the plugs and got the MMo out installed new plugs and she lit off right away and ran like a champ!So thanx for all the help it is much appreciated. Pete.

 

I don't want to insult you but you mentioned that you checked a bearing.
Is there any chance the bearing cap got replaced turned backwards?
A mismatched bearing cap can cause binding and a hard to turn crankshaft.

 

With the plugs out, 40 ft-lbs should turn it with ease.

Bob

 

Not so much that the rings are stuck, rather the oil on the pistons and rings drains down and you don't get a good compression seal at the cylinder walls.

Bob