If it is pvc why not glue it. If it is steel I would use a union. If you cannot do any of the above I can see using a compression coupling. You should be able to feel when it is tight enough. No lubricant is necessary.

"what sould the com be on a 5hp b&s engine. i put a new head gasket on it,im getting 30 psi. wasgetting 0 before, the valves seem to be working but i cant start this leaf blower for nothing, im getting gas & spark. How long should it hols the 30 lbs." Let's circle back to what the original poster was asking about and re-read what he said. He was getting -0- before and 30 psi after a head gasket change. To me that indicates the possibility of a warped head - or a poorly installed new head gasket.

***"But my new question is why ?"*** Can't say for sure but I recommend that you get back to the tractor and do a very thorough inspection of the air filtration set up, carb mounting gaskets, intake manifold gaskets, carb throttle shafts.......any place or location where dirt, dust, grit might possibly enter the induction stream. I recommend doing that because, as you said, "valves don't stick while the engine is running"!!! I'm sure there have been some exceptions to this "rule", but largely, for a valve to stick open, it had to have been open at the moment the engine stopped when last shut down. ........................................................... Now, to speculate about YOUR stuck valve, and the future of your engine. What you experienced may be due to a combination of varnish and possibly dust/dirt on the intake valve stem. That is why I say you want to really check all the places fine particulates can enter the induction stream. But, even if dust were PART of the problem, I feel that varnish is the bigger problem. ***"I'm thinking of running some top oil in the gas for a while ? What do you think ?"*** I highly recommend that, not just for a while, FOR-EVER more! I also recommend using gasoline stabilizer in all your fuel cans/jugs all the time, so that your fuel is stabilized while it's waiting to be used. Storing unstabilized fuel, and then adding stabilizer to the tank is pretty much a waste of time and product. I like to add Stabil or Seafoam, along with 1 oz. per gallon of Marvel Mystery Oil, to my gas cans BEFORE I fill them at the gas pump. I have simply made this "my ritual". The benefits of adding "top oil" (a.k.a. "upper cylinder lubricant") are: The oil leaves a very light film of lubricant on all surfaces of the entire fuel system, this means that all the things that are exposed to the fuel, also receive a light dose of lubrication, where they formerly got none (using "plain pump gas"). This light film may offer some protection against wear and corrosion to the "innards" of carburetors (float hinge pin, needle valve retainer clip, fuel solenoid plunger, etc.) The "top oil" in the induction stream will also afford a bit of lube to the choke shaft and throttle shaft pivot points that would otherwise also never know what oil is. The intake valve stem is situated squarely in the induction stream. This means that the valve stem is constantly "washed down" by the liquid fuel droplets in the stream. This "wash down" amounts to a solvent bath to the valve stem, removing the light film of engine lube oil that was on the valve stem. Some of this solvent gets into the valve guide and that is where a valve "sticks". By adding "top oil" to your fuel supply, you assure that the liquid fuel droplets being fed to the cylinder contain a bit of lubricant. The gasoline portion of the fuel will evaporate from the valve stem but the oil will remain. This oil coat helps prevent solid varnish from forming on the valve stem and that reduces the chance of a valve becoming "stuck" (I sometimes say the valve "gets mired up in varnish"). I will also advise that frequent oil changes are beneficial to help remove some of the "bad stuff" in the oil that can also contribute to the formation of varnish. You might consider changing the oil in that engine twice as often as you have been doing it (now that you have "looked the devil in the eye").

Yep, like I said. The wrong info is MMDDYY. The right info is YYMMDD & ASSEMBLY LINE AND MANUFACTURING PLANT. Also, would that part number 790400 (698492) be the latest greatest version or the original duplicate? If original, would it be better to opt for an improved version? Thanks Found a pic of similar cam with CR here: http://www.doityourself.com/forum/outdoor-gasoline-power-equipment-small-engines/334366-briggs-stratton-28n707-15hp.html Here is a link that might be useful: Pic of cam with CR at bottom of thread.