Farmall SMTA Valve chatter issue

I've got a smta. When you load it hard or rev it up, the valves chatter a lot. Just finished headvgasket replace, still smokes some when revving hard, and chatters. Installed a 450 head, with new valves guides etc. Reused old valve train. Timing light says it's on time on number one. I know I need to retorque and re gap valves, I understand there will be some chatter but mineis too much. Please advise
 
ya but have you set the valve lash to .017?now?
also i am sure that a 450 head was longer valve stems than the super m head. so if you have not checked these things out you have a problem .
 
Guessing the time is advanced to much. Need to check the static time and distribtor advance. Or you have a piston to valve clearance problem.
 
Valves dont clatter unless loose or over reved (3000rpm would do that, but unlikely to be your issue) What you are likely to be hearing is spark knock. I believe your timing is either too advanced (possibly wrong timing mark, or other measurement issue, or the advance is not working.
Another issue is fuel. If a 450 head and other compression enhancing factors like bigger bore, or popup (domed) pistons were used it might need 92R+M/2 Premium fuel. If you find fuel to be the issue, retarding the spark with a different cam plate in the centrifugal advance might be a way to avoid knock and use regular. Jim
 
So basically, get it warmed up, i want to retorque the head to insure nothing has backed off, reset the valve train assembly, reset the gap in the valve train to .017, then look at the timing and possibly retard. There does not seem to be much adjustment in the movement of the ditributor, so do I need to remove the geared pin in the distributor that has the cap on it and retard from there or what?
a97000.jpg
 
here is some #'s from my w-400 head when i had it rebuilt.
valves: 362436 r1
length: 6.070
exhuast:36.i6
intake :15.01
i am sure that these are longer than the standard m valves. anybody have valves they can measure.
 
the wire terminal on dist. is to be positioned at 3 oclock position from factory.and #1spark plug wire is at 2 oclock position. this gives all kind of retard and advance travel when you loosen the two dist hold down bolts and turn accordingly.
 
So are you talking about turning the cap to retard? or Finding top dead center of number 1, then remove that rotor cap in distributor to 2 o"clock while the spark plug cap on distributor is at 3 o clock right?
 
Here is a picture of the Distributor. I basically need to find top dead center #1. Spark plug cap at 3 o'clock, rotor in Distributor at 2 o'clock?
a97006.jpg
 
no, i am saying that #1 spark plug goes to 2 oclock position on dist cap... thats a factory position. the little screw for the points on the distributer goes to the 3 oclock position... from factory. i am saying this cause i dont know what how your dist. is positioned and you say you have no travel. or just post a pic. of dist on tractor. you have to have dist. in proper position to get proper travel. once this is found out will go to next step.
 
ok, now thats what i thought. that terminal with the wires needs to be at 3 oclock, which requires pulling the dist out and getting it in proper order.same with the plug wires there not correct either. now next step.
 
now get #1 cyl. on compression at tdc.
take out the 2 dist bolts with clamps and pull out dist.
have cap off, turn rotor to 2 oclock as viewed from behind. hold dist so wire terminal is at 3 oclock and reinstall dist. leave bolts slightly loose.
recheck your timing marks on front pully make sure correct.
turn on ignition and rotate dist clockwise a bit, then turn counter clockwise till you just hear the spark snap. that is where you tighten the dist and you are timed.thats it. good luck
 
the terminal that is jammed into the coil and preventing rotation. it has to be at 3 oclock not 12 oclock as pictured.
 
Most times a timing light is not to successful in setting the time at idle on those tractors. Unless the advance springs are in good condition and you get the idle down to 400 RPM or less.
After you get the distributor in the correct index and the tractor is for work. Looking at the crank pulley from the front, find the TDC notch. Go clockwise and mark the pulley 1-11/32 inches from the TDC notch. Use the timing light and set to that mark with the engine running full throttle. If the initial engine stopped timing is off after that or no smooth timing change from low to high RPM the distributor has the wrong advance or bad advance parts.
If the engine already had higher compression pistons before the head change that makes it more important to know the total timing.
Your engine came with a 30 degree total advance.
With higher compression and max loads you want around 22 to 25 degrees total advance. Unless you run a higher octane fuel.
Think you need a operators manual to get the basics about timing the distributor to engine.
 
You better go back and look at your parts books again. Intake valve 362435R1 and exhaust valve 362436R1 fit M's, Super M's ,400's and 450s.
 
Valves number 50731 (intake valve) and valve number 50732 ( exhaust valve) were used in heads number 8574DC and 8060D for W6.
 
sooo then how come the w6 and the farmall m have diff. valves or is it they did not use that same w6 head? i knew i run into diff. valves on the w-400 and i am sure it was the stem length.
just want to know, now that it has me going.
 
JUST distributer, the 2 5/16 bolts that takes a 1/2" wrench. that have a special clamp to allow the turning of dist. that is the only way you will get dist in proper position.you need to remove coil to get at inside bolt. absolutly no reason to remove pump or housing in front of pump.
 
Rustred I have to apolgize to you I just found some incosistency in my catalogs. I went into another catalog that they are specialists in only Farmall and IH parts and they give more information. They have the W6 and M as a 248 cubic inch gas engine but they use differant valves in the valve train and they give head numbers that where used. They have the SuperM,400 and 450 gas and LP as a 264 or 281 cubic inch engines and they use several differant head numbers and differant valves. When I do my rebuilding I don"t order out of catalogs I take parts and match up parts where ever I buy them.
 
ooh no problem, just good we got to the btm of this valve situation. thanks for the time spent.
i just had a feeling that the 248 was different from the 281 in my w-400. i do the same with parts matching and just remembered this from about 10 yrs. ago.
 
if you rotate the dist 90 degrees clockwise then move the wires back 1 hole counter clockwise wouldn't that correct the position of the coil wire bolt or won't it rotate that far without being removed
 

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