WC Static timing question

Raptor44

Member
I'll try and make this painless.
1940 WC Tractor destroyed in fire. Eng # on L side of engine starts with WD. ???? Boss wants it redone. All is progressing well.
Engine is on a stand so flywheel is removed. Timing is disturbed since the Mag and mag housing have been removed from engine. Actually mag melted. Since engine has been turned to facilitate pre adjustment of valve lash on refurbished rocker arm shaft. I have read and i have seen much different input on how to static time this thing. If I bring the engine to TDC it appears that there is a marked divit between the cam gear. Does this mean anything? What procedure from beginning to bolt the housing in. At what position should the lug be in before I install the mag? Now where in relation to all of this is the F mark on the flywheel be located? This is the first tractor that I have had the priviladge to work on. Really enjoying it. I am a car and bike and helicopter nut. Now I am wondering why it took me so long to " get with it". Any input would be welcomed. If I can figure out how to post pics I will. Thanks for the help.
 
bring no. 1 piston to top dead center,(be sure it is on compression stroke, you can tell by watching valve action) mount mag and rotate until it clicks. the mark on the flywheel can be seen through a hole in the bell housing, but since you have the flywheel off this is of no benefit. the impulse coupling, the thing that clicks, retards the spark while starting. when it starts the spark is advanced about 27 degrees. those old FM mags were not too good. better to replace with a battery dist, unless you want to keep it original.
 
You should have a manual for the engine.
There are marks on the crank gear, the cam gear and the mag gear that
must line up. The flywheel can only go on 1 way, so you can't get it
wrong. Don't worry about mounting the mag until the engine is back in
the tractor. Then remove the front spark plug, and with your thumb in
the plug hole turn the engine until you feel air being pushed out of the
hole.I use a wire and feel when the piston is at the top of it's stroke.
This is TDC. The mag slot should then be at 9-3 o-clock position. The
mag is then turned to get the rotor at the timing lug which is near the
position of #1 plug wire. then turn the locking bar backwards to match
the slot. LOL Bob
 
30398.jpg
 
All engines four six or eight cylinder car truck or tractor static time at TDC on the compression stroke for number one plug. The drive slot has to be horizontal for a magneto. If the crankshaft gear is timed properly to the camshaft gear it really does not matter where the drive slot is located for a distributor. You can lift the distributor out and point the rotor in the direction of the number one spark plug wire terminal as you set it back in.
 
Update on this tractor. The flywheel only bolts on one way so it is was a no brainer. When all was said and done(tractor now finished). I put a quart of fuel in the tank, pulled the choke gave the starter a thump. This engine mad about a turn and kicked right in purring like a kitten. Thanks to all this is a sweet tractor.
 
Thanks for the update...it's always good to hear a success story. Would be great if you could post some pictures of this tractor...if you have before and after pics makes it even more interesting - Thanks!
 
I will post some pics soon. However I have run into a problem that I am in the process of trying to resolve.
Although I thought the tractor was running great I noticed that the paint wasn't burning off the exaust manifold for Number one cylinder. When removeing the new spark wire from number one there is no noticable decrease in rpm or engine sound yet all other cyl have a noticable decrease.
Tried swapping plugs and wires still no change in Number one. Compression in #1 was 95. #2 was 85. #4 was 95. And #3 was 95. Rechecked valve lash and #1 went to 100psi.
Started playing with magnito. Original setting shows a 1/4 long arc in the window. reindexed the gear (advanced one tooth). Now there is no arc but a good spark in the window and it seems to run a little better but still no firing on the number one cylinder. Could it be a bad head gasket pulling fuel from #1? This thing is awsome just want it to be 100 percent. Checked intake for good seal and appears good. Starts and runs great and drove it around. It feels good but paint isn't burning off manifold and no decrease in RPM that indicates I still might have a problem. Any Ideas or am I right about the head gasket? thanks for help.
 
Are you saying that when you pull the wire from #1 plug you can get a blue spark that jumps from the wire to the plug?
Or do you not?
 
It looks to me like you have a Wico mag. Not a FM. The wico mag the white mark on the rotor should be lined up with the window in
the cap when the mag is set on #1.
 
wilco mag. Yes. The mag is firing. The plug is firing. The cylinder is not firing. The spark I was referring to was in the mag window. Have a laser temp gone that I am going to use today.
 
Great piece of information on the Wico. I sent away for a book and this is not what I recieved. I will print this. Thanks. This magnito is New out of the box and Is working as advertized. I am getting spark to the plug at the proper time. Cylinder is just not firing. I hit it with the lazer temp reader as soon as I started engine. #1 cyl would not come up to temp. Checked all plugs while running and the number one plug was much cooler than the other three. This also tells me the cylinder is not firing. I got the tractor Blues........
 
Well we have exhausted all attempts to get this cylinder to fire. I will pull the head today and delve further. It is the only thing that was not done since the fire. Prior to that incicent the tractor ran great. I had replaced lower end seals and rebuilt the oil pump and replaced pan and side cover gasket, rebuilt the rocker shaft, new carb and new mag. Now onto the head gasket. We believe the engine is now also picking up a little water in the oil so no choice here. Hope the head didn't get to fried. Any thoughts?
 
Well I have removed the head and really couldn't see anything unusual. Barely a ridge at the top of the cylinders either. All looks good. Head is going to the shop for a pressure check and perhaps a light milling. Again any thoughts would be appreciated?
 
Sounds like you have checked everything, but could there be an obstruction in the manifold at the head to that cylinder ? That WC looks really great, you'll get it figured out.
 
Not a chance of that. I had sand blasted the manifold while it was off and then ran High pressure clean air through it with a one inch line befor painting it. No the problem seems to be just an old worn out head. #1 cyl valve was paper thin and the seat had been pounded. Valve springs were very weak. Intake stroke was probley sucking the exaust valve down a bit. Spring was that weak. Guides were also worn even though it didn't smoke. Seals were also shot. So the head is going to get rebuilt. Parts are on the way. Glad you all like the tractor. It's the first one that I have done. Working on restoring a 1945 John Deere hand crank B model also.
 
Update on this AC. The Two valves were really shot. Low and behold #1 cyl. Valve chipped and both had no margin at the top. One bad valve seat. All guides were worn. The seals crumbled to dust. All the springs were totally shot. Replaced all. Just installed the head, rocker assembly did an adjustment and touched up the paint. Installed new manifold studs. Will let it sit overnight and let the thread sealer set before I load the water and oil. Bolt up the manifold and give it a hop. I am excited again.
 
Its finished. Runs great. Nice and smooth. Drove it around for about an hour out and about and up and down some good hills and gov works as advertised. Left brake is a little weak but the right one is enough to stop this thing real easy. I think the boss will be happy. Thanks for all the input.
 
Well it may run great, but still picking up a little water in the oil. Since it's a wet cylinder design I am going to guess that perhaps some of the two O-rings at the bottom of each cylinder sleeve may have been damaged in the fire. Since it's not picking up a lot of water I am going to proceed with some Moroso All Weather Seal. Have been told this is a good product. So I just finished draining the Rad and Block and will flush and follow the instructions and see what happens.
 
Well that appeared to work. Finally. Now I'll wash it and shine it up and park it. After I pull a small stump. LOL
 

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