My 8N has a serious clatter. I hope its just valve clearance.
I got the specs. and I see a panel behind the manifolds that must be where you adjust valve clearance (???) on this flat head engine. I know a stud bolt will twist off it I try to remove the manifolds and then I'll have a real mess.
My question, Is this the right panel and will it come out by just removing the carb? It don't look easy to get at.
I can't tell you specifically about clearance for getting it off but that is the access panel for valve adjustment. On some engines you do have to remove the manifold(s). You will need some thin wrenches (called tappet wrenches). You may need for them to be bent to reach all the tappets with the manifold(s) on.
If your manifolds are held on by studs and nuts it is usually fairly easy to get them off as you can work on the nuts easily or just cut them off. I have found that in addition to the usual penetrating oil, heat, etc., one of the best things to do in any case is to hit the nut really hard with a six-point socket and a spacer, like you are trying to drive the nut tighter onto the stud. This often works for bolts also. You can generally hit it hard enough to free the threads without damaging anything. I use a good sized hand sledge hammer.
Can you even adjust the valve spacing on those? I've been _told_ that the Model A engines that they're based on required you to grind the valve stems for adjustment, but I'll happily stand corrected if someone with real experience tells me different.
(I've also been told that later flat head V-8 engines had adjustable tappets, so...).
I like your suggestion, just beat on it, but I'm having trouble visualizing exactly what you suggest. Are we driving on the nut itself with a socket smaller than the nut? Kinda like driving a nail? Or, are we trying to rotate with impact? Kinda like hitting on the end of a combination wrench?
I can see any of this is a long shot. The stud bolt is exposed for about 3/4 inch from the base of the head to the top of the manifold and is horribly corroded. Its just going to twist off here on at least one bolt.
Have you visited ytmag.com (Yesterday's Tractors)? They have forums just for people like you and me. If the engine is running well otherwise, why not just take the muffler off so you don't hear the clatter? ----Only kidding.
Yes, I was suggesting driving on the nut with a tube which fits over the stud but smaller than the nut. I have used a deep six point socket which fits the nut but with several nuts stacked inside so it only goes part way over the nut. If you have good access you may be ahead by splitting the nut to start with. I like to use a narrow chisel sharpened to a somewhat sharper angle.
I am sure that someone on the tractor forums can give you specific advice on adjusting the valves. You need to be prepared for the worst case of course, which would be to drill and re-tap for one or more new studs.
I got lucky, the manifold came off. A better person would replace those stud bolts. I'm just getting new nuts and trying again. The problem wasn't valve adjustment. It was exhaust gas leaking. The leak was small enough that it didn't make a pop sound but more of a clatter.