Won`t start

B

bottomfeeder pete

Junior Member
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? Any light you can shed on this matter would be much appreciated,thanx. Pete.:confused:
 
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on mine, it spins at a fairly good speed. not too fast, not too slow. I have autolite plugs in mine and they are excelent! check connections, make sure they are clean and tight. ive had this same issue with mine.
 
Make sure you have the fireing order right, and keep in mind, the
number one cylinder is the passenger side (right side) front cyl.












.
 
49 It is great to see you passing on some of the info that was given you. That is what makes this hobby so cool. ( pay it forward ) Bill W
 
Pete If the engine and components are all set up proprly and in good shape the engine doesn't have to "spin", as soon as the first piston comes up it fires. Check the spark the plug wires to a head nut as it cranks. If you have spark spray a couple of shots of starter fluid down the carb as the engine is spinning. If it fires but won't run the gas isn't getting to the carb yet. If it fires on the starting fluid keep giving little shots to keep it running. I have had some that take a minute or so to finialy get fuel. I'm not in favor of pulling these old engines apart just to "look". You can perform a lot of tests right on the floor with just the intake manifold removed. Compression,valve clearance, oil pressure and even adjust the oil pressure. Change the oil before testing. I have a lot of engines that sat 50 years and they run and sound like new engines. As I always say, do the easy things first. G.M.
 
Thanx g.m. I did try starting fluid and not a pop,The firing order is right all connections are good and it has spark my compression gauge is junk but i got compression trying to blow my finger off the holes, I guess i should get a good compression gauge.I am getting fuel both carbs are squirting fuel,could the marvel mystery oil in the cylinders be the problem This motor has not been started in fifty years, that is why I opened her up so I would know what i got and everything checked out I did not want any issues Heck I even pinned the oil pump gear.
 
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Pete the only ill effect the MMO could cause would be fouled plugs. Check ALL of the plugs for gap and shoot some carb cleaner in the plugs to dry them. I question the size of the spark or timing if it don't at least try to fire with starter fluid. How about dirty air cleaner? I'm sure the air cleaner is off. Points get a film on them sitting for a period of time. I run a peice of a business card between them with carb cleaner on it. I have had some that wouldn't fire even with gas but fired with starter fluid. After the initial start they worked after that. One good thing from this delay is the MMO will soften the carbon in the rings. I still say the tear down was unnessary at the point you did it and hopefully isn't the root of the problem. G.M.
 
Did you turn the crank while you had the heads off? Do know if the valves are opening and closing? I would say some valves are stuck open. Just a suggestion.
 
Try 18 volts to the starter for a couple minutes cranking at a time ,a 12 and 6 in series .but keep the current coil voltage ,
 
I did check the valves and they were going up and down and the seats looked fine,I think if any thing the rings could be stuck,going to get a good compression gauge and check comp.
 
No one has addressed the fact that using 12 volts did not seem to increase the starter speed appreciably. 12 volts will spin a good starter very fast. A sick starter will rob enough juice and the engine will not start (been there, done that). Also the MMO could have fouled the plugs.
 
compression is low,I believe the rings are stuck. The engine had been ran about 10,000 miles before being left to sit since `62. Oil in the cylinders Does raise compression,but not much.I put mmo in it,But don`t think it was enough how much would you guys suggest and I just shot them full of kroil.Thanx for all the input!
 
if you have some compression, fuel in carbs, proper spark and firing order,dry plugs. ive had pretty good luck putting about 10 squrits of oil in each cyl cranking it over,put plugs back in and pull starting it with a good helper doing the pulling.make sure you have new non duluted oil in the crankcase.its worked for me several times over the years.p.s.make sure exhaust isnt plugged.
 
Not trying to be a wise guy but I presume you are aware that Ford numbered their cylincers diferently than other mfgr's. Nos. 1-2-3-4, front to back, on psgr's side and 5-6-7-8, front to back, on drivers side. Just a thought. Good luck.
 
The MM oil may have fowled the plugs ,You seem to be getting voltage drop so A quake burst with 18 volt will not hurt .Prolonged use will,But as 51 Merc says find the problem it should start on 12 volt ,you could wash out the MMo by a 1/2 cup gas in each cylinder .wind it over with the plugs out .
 
I had a similar problem..

I was getting spark to the plugs sometimes but it was a very weak spark. I had my coil rebuilt by Skip Haney and it fires right up now with no problem.

Maybe your coil is bad.
 
It should fire or pop regardless of compression. Triple check firing order.

6 or 12 volts should be more than enough. If you put a timing mark on the crank pulley while it was apart you could try a timing light.
 
One cool thing about flatheads is that they're easy to run badly. That's an awkward sentence but what I mean is that if you get basic fuel, air, and spark, they will run on four cylinders with little to no compression on bad gasoline.

If it won't start or even stumble badly, there must be a big obvious problem that you haven't looked at yet.
 
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