Q:   Why does my 5hp. Galloway backfire out through the exhaust?  Seems toonly do it after ~30 minutes of running.  Not every hit, but occassionally.I have not went into this engine, only re-timed(?) it.  Another thing Inotice is that the intake valve really pulsates when it's latched up. (Needsan "Economizer" huh, Herc. gang?:-))  Seems to have reasonably goodcompression.Sure could use some help on this one!RickinMt. ricandkath@msn.comhttp://community.webshots.com/user/stroberc

A:Is the exhaust valve getting hot and hanging up?Ed This e-mail address is being protected from spambots. You need JavaScript enabled to view it

A: Possibly a leak in the exhaust line somewhere between the head and muffler,draws air(oxygen) into the muffler where it forms a combustible mixture with unburntfuel, and the occasional spark ignites it after she warms up a bit.Powwie!!I'll never admit to devising a system for just this effect in my '26 Chev 4with satisfying results in my callow youth.JW This e-mail address is being protected from spambots. You need JavaScript enabled to view it

A:You need a stronger intake valve spring or your exhaust is restriced at themuffler and your engine cant breath when latcher out.EDD PAYNEPO BOX 364 GULGONGNew South Wales  This e-mail address is being protected from spambots. You need JavaScript enabled to view it

A: .  Another thing I>> notice is that the intake valve really pulsates when it's latched up. not sposed to do that dude Chuck Balyeat This e-mail address is being protected from spambots. You need JavaScript enabled to view it

A:Yea, Chuck..if the intake pulsates, then the flutter valve has to followsuit..viola, instant rich mixture for the next hit. So possibly the exhaustis partially plugged or the exh. valve isn't opening far enuf.  I haveplayed with spring tension on the intake valve.    Think it's time to pull the head.ThanksRickhttp://community.webshots.com/user/stroberc

A:<Why does my 5hp. Galloway backfire out through the exhaust?>This is a very common misnomer in engine circles! What you are experiencingis an after fire, not a back fire. A true back fire would have gases blowingback through the induction system - NOT a good thing!  I don't know whythe phenomena you are experiencing has become commonly known as a 'back'fire, but there you go. <g> I would guess that your weak inlet valve springis the most likely cause, as the engine must be drawing some fuel in whencoasting and this is no doubt collecting in the exhaust. To rule out exhaustrestriction try running it with the muffler removed and just a short lengthof pipe in its place. The second most likely is a sticky exhaust valve whenhot. In more sophisticated engines there can be other causes for afterfiring, such as incandescent carbon, late valve timing etc., but I thinkyour problem is much simpler.P.S. I don't know how it is with your Galloway, but it takes my 10 hp M typemore than half an hour to get up to full operating temp.! RegardsBrad

A:    'preciate the help, guys!!  Probably should receive a small pistolwhippin' for even running a engine without looking at the valves (stems)first.  I've seen some pretty sad ones in my short time.    I'm leaning towards thinking that the exh. valve isn't opening farenough due to wear on the cam roller and also at the rocker arm.  And itsure could be sticking.  The latch also needs some sharpening..think itfalls off occassionally.Take Care..sorry to say "lots of cold air headed your way."  Looks like it'shitting "Down Under" also.RickinMt.http://community.webshots.com/user/stroberc

A:>From what you've related, I'll -almost- bet (I don't gamble 'cause you can't beat the house) that the cam timing is off one tooth.  Since you hoicked-up the intake spring and it didn't make a difference, it's just about gotta be the cam timing.  I'd guess that, on a 5HP engine, you should have an exhaust lift of -at least- a quarter inch to keep it from sniffing fuel when latched-up.Advance the cam timing one tooth and go through the mag/ignitor adjustments and valve lash (a lot!!) and it should run right.If you can't figger it out, it should be fun at shows.  Pop.......huff, huff, huff, huff, huff, BANG, Pop......, etc.Ahh, yes........you've gone into orbit.  Everybody has to do it at least once!  I planned my time so that I didn't have an audience.  Less embarrassment that way.     No need to pull the head unless you just want to have a looksee.  It's obvious that the valves are seating and carbon won't make THAT much of a difference in the running.  I can't imagine carbon causing the muffler explosions.I don't know much about Lunkenheimer mixers but I don't think that "flutter valve" adjustments will make much difference unless the explosions are due to lean mixture.  That oughta be easy to diagnose.Continue to have fun!Take care - Elden DuRandKentucky, US of This e-mail address is being protected from spambots. You need JavaScript enabled to view it <mailto: This e-mail address is being protected from spambots. You need JavaScript enabled to view it > This e-mail address is being protected from spambots. You need JavaScript enabled to view it <mailto: This e-mail address is being protected from spambots. You need JavaScript enabled to view it >

A:Elden, You probably weren't on the list when I got this "saw-rig" 5hp.Anyway I was told by the PO that his kids had it running.  So dummy me tookhis word for it, gased it up and went for it.  Had a foot on the spoke. Upagainst the wall I flew and slowly gravity took over, ending close toterminal velocity:-((  Landed on some boxes, not hurt, spectators all over,great big smile came over my face.  "Hey, this baby wants to run!!!"    Galloways do not have timing marks, so it's a matter of doing the degreething.  I've got it close.  Need to study the book more on pushrodadjustment and timing gear placement, and how they relate to each other.    One thing more, The Lunk., flutter valve stem is homebuilt, and I'mplaying with spring tension on that.    I have added more tension to the intake valve spring using ascrewdriver..didn't seem to matter much.    But, I will pull the head today and take a look.  I have "sinkingfeeling" dreams about the valve stem(s) and hole in the piston.    I'll guaranteed you..the muffler is not plugged...mainly the reason forKathy saying: "Damn, you smell bad."    later, thanks Elden!!    Rick

A:Rick:You should be able to adjust the exhaust valve to give enough opening without affecting the cam timing too much.  It could be that someone in the past got the timing a tooth off and had to mis-adjust everything to get it to run at all.  In a-thinkin' on it, I'd say if it's the timing, you're advanced one tooth.  Now, in order to get the valve to open late enough for the engine to run, the cam is almost at it's highest point and the valve is just barely opening.  You're a smart guy - you should be able to figger it out.Remember that if you shift the cam timing, you will also have to adjust the valve and the ignitor/mag trip to get everything back into some kind of syncopation.What -I- would do if the timing is right and the exhaust valve is opening enough and the muffler isn't gommed-up would be to get the engine into its' "backfire" (muffler explosion) mode then (wearing a glove 'cause it might be hot) gently pull back on the intake valve or pull up on the spring to increase tension to the point that the valve doesn't flutter when the governor is latched.  When you do that, the problem should go away.  I'd -almost- be willing to wager that the intake valve spring has gone sorry on you.Take care - Elden DuRandKentucky, US of This e-mail address is being protected from spambots. You need JavaScript enabled to view it <mailto: This e-mail address is being protected from spambots. You need JavaScript enabled to view it > This e-mail address is being protected from spambots. You need JavaScript enabled to view it <mailto: This e-mail address is being protected from spambots. You need JavaScript enabled to view it >

A:Thanks Elden...after removing some important parts and finding them andother items very badly worn, I've decided to bag it for now and put it onthe backburner.  I was hoping for a quick fix, but it is a hard starter andhas too many strikes against it,,paralleling my ticker.  whew!    It will have to wait..I'm going to concentrate on making my shop morefriendlier this year.  I've also got 3 old iron projects going on now.    I'll bookmark your post.Take Care,Rickhttp://community.webshots.com/user/stroberc

A:If you MUST remove the head, give the bolt a couple of hard belts right on top of its head before trying to move it either way a little.  Smacking the bolt head will sometimes shock the rust bond and let you finesse the bolt out.As for the tramming, big deal.........  Just advance the cam one tooth.  If you can adjust the exhaust valve lash so it starts to open about 20 degrees (more or less, kinda, sorta) before bottom dead center on the power stroke and it has plenty of lift, all you have to do then is to get the ignition timing readjusted so it fires a bit before TDC.  If your engine has a spark retarder on it, set the timing so it fires at TDC with the  spark retarded.......a good starting point.  TDC is good idling territory.Take care - Elden DuRandKentucky, US of This e-mail address is being protected from spambots. You need JavaScript enabled to view it <mailto: This e-mail address is being protected from spambots. You need JavaScript enabled to view it > This e-mail address is being protected from spambots. You need JavaScript enabled to view it <mailto: This e-mail address is being protected from spambots. You need JavaScript enabled to view it >

A:Rick:I will add one thing to my suggestions and you may have the problem in a nutshell.  I didn't immediately pick up on your statement that the governor linkage is worn.  If the governor trip lever/detent is -really- worn and can't be adjusted to the point where the pushrod only moves a little when latched-up (just enough to release the lever), that could easily be the trouble.  If the valve moves a lot while the governor is latched-up, it is causing the intake valve to open (if only a little), thus filling the muffler with air/fuel mix........BANG!I wish I knew more about the configuration of a Webster (I'll have to look on Harry's).  If it's possible without harming the magneto, you might be able to isolate the "hot" wire to the ignitor and, using a double throw switch (center to ignitor, one side to magneto and the other side to a low tension coil).I'll about bet that the Webster holds the points closed all the time except for when it trips.  In that case, be careful to not leave it in the "battery" position too long or the coil will get really hot.If the Webster will allow (and I think it will), you might be able to rig-up a way to hold the mag in a position where the points are open.  After priming, just remove the 'rig' and give the mag a twist.  Once the engine fires a time or two, you can throw the switch to "mag".Take care - Elden DuRandKentucky, US of This e-mail address is being protected from spambots. You need JavaScript enabled to view it <mailto: This e-mail address is being protected from spambots. You need JavaScript enabled to view it > This e-mail address is being protected from spambots. You need JavaScript enabled to view it <mailto: This e-mail address is being protected from spambots. You need JavaScript enabled to view it >