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Discussion Starter #1
The problem happens to be on my 1988 Troybilt Super Tomahawk Shredder/Chipper, but I suspect it is common to everyone with a B&S upflow carb. The carb needs an overhaul, it will kick over with starting fluid but zippo with gas.

Carb removal would be easy if the muffler had not been positioned to prevent access to one carb bolt and one elbow intake bolt.

Two weeks of soaking the lock nut ring on the muffler with Silikroil has achieved nothing, it is immovable.

There was enough room to get a long impact screwdriver on the left bolt of the intake elbow, at a slight angle. It was not enough, the Philips head disintegrated. I tried the right side bolt head on with an impact drill, and it did not budge.

The muffler is on a short length of 3/4" pipe.

If I had a torch I would try heating and ice quenching to break the bond, but that's a non-starter.

The only possibility I see is to try and drill a hole in the lock nut. If a hole is drilled, then successively using a larger bit may mean I can use impact to snap the ring apart.

The location is awkward, getting a hole started is going to be difficult at best, and may not prove feasible.

I am hoping that some of you may have encountered this problem before and have better ideas.

IMG_20201017_200654_800.jpg
 

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I have encountered those mufflers in the past, and had no issues soaking them with a good penetrating oil like Trizol,, letting it sit a few hours, and then just tapping the lock ring on its tap tabs as intended.

Do you have an air hammer?

You probably want to replace those rounded Philips screws.

After you get it apart, some never-seize on install is what I usually do.
 

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You may be able to take the carb off at the intake,leaving the intake bolted to the block,but first you must remove the main jet emulsion tube from the casting with the proper sized flat head screw driver,if it is acessible..

Maybe an offset screwdriver would fit in there to get that phillips screw out,or use a short phillips bit normally used on a drill to drive screws, and a 1/4" ignition wrench on the bit to get it loose..
 

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Discussion Starter #4
"...soaking them with a good penetrating oil like Trizol"

Unfamiliar with it, Google tells me Trizol is a DNA reagent.

PBlaster and Silikroil have both achieved nothing, and neither has failed me in the past, so suspect there is more going on than rusted threads.

The Philips heads are fine, the Philips themselves not so much. The fact that the right bolt did not move with an impact drill kept bothering me, so went looking for a likely explanation.

The https://www.agweb.com/article/in_the_shop_bustin_bolts description of galvanic corrosion fits my situation, just have to hope it is not true....


"You may be able to take the carb off at the intake..."

My efforts with a 1/4" wrench and short bit got me nowhere but will try again and if successful will replace Philips with a hex head for 'next time'.

"...you must remove the main jet emulsion tube from the casting"

That is unclear to me. On this carb the emulsion tube is accessed from the bottom e.g.
is an example (notice how easily his muffler screwed out, but from the looks of it, it was not easy). Note that this carb had hex heads on the intake, and mine has Philips.


IMG_20201018_094754_800.jpg

IMG_20201018_094821_800.jpg
 

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I can see how tough that is. I just worked on a similar one.
Couple questions-
Do you have a propane torch?
Do you have a Phillips no. 3 bit?
 

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As mentioned, an air chisel with a dull or punch end can be used on the jam nut. The jam nut being on the exhaust nipple that is screwed into the exhaust port. Position the punch, with a squared end, onto one of the teeth of the nut. Whack hard with a ball peen or sledge. It should break loose, and be able to be screwed away from the engine. Then you can squirt some 'stuff' onto the pipe threads, and apply a pipe wrench to the muffler. An impact rather than a hard pull seems to break this kind of rusty bond a lot better. The hard pull will mostly bend stuff, or crush the tube. Then again, a muffler is not expensive. But if you decide to destroy the muffler, leave enough pipe behind so you have something to work on after you fiddle with the carburetor.
You could also dent the side of the muffler to gain straight access to the remains of the philips. Along that line, you could cut or grind a slot into the philips so a flat blade could gain some traction. If you don't have them, a tiny Vis-Grip is soooo nice to grab onto the sides of screws that don't want to come out. You can even file a flat onto the side of the head, and the grip pliers or even an adjustable wrench will use the flat as if you had a bolt vs a screw.
tom
 

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Discussion Starter #7
"Do you have a propane torch?"
"Do you have a Phillips no. 3 bit?"
Yes and yes. One down on #3 bits from trying to remove the intake elbow bolt on an angle.

"Whack hard with a ball peen or sledge. It should break loose, and be able to be screwed away from the engine."
I agree, two weeks ago I thought it should too...

No air chisel, have had to rely on a punch and a 5lb sledge hammer.

"The hard pull will mostly bend stuff, or crush the tube."
That's good to know, I thought it was 3/4" pipe that would take a lot of abuse. I can think of no way to create an impact, it will have to be brute pull.

"to the remains of the philips...you could cut or grind a slot into the philips so a flat blade could gain some traction."
All the Philips heads are fine. It was the tip of the Philips bit which shattered on the intake elbow bolt.

"You could also dent the side of the muffler to gain straight access"
I like that idea. It will let me access the Philips head so I can remove and re-furb the carb.

Look Ma, no carb!

Kudos tomw0, it took < 5 minutes to use your idea to resolve my dilemma.

IMG_20201018_151422_800.jpg
 

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Well that’s great!
Tell me, how did you get the Phillips off? I thought they were also too stubborn and would not move for you. Did you prep them with penetrating oil? Was your impact cordless or old school mechanical?
 

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Discussion Starter #9
The Philips on the intake elbow go into the block (first photo top center), and they are immovable. The muffler prevented a straight line on the left bolt but there was better than a 75% connection. When I triggered the impact the tips busted off the bit. A 100% straight line on the right bolt with the impact did nothing. The impact is an 18V Makita.

The Philips on the carb (first photo bottom center) were screwdriver easy, no penetrating oil, just some initial resistance.
 

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I assume you dented in the muffler a tad to gain access to the screw at the carb to intake--my eyes cant tell by the photo..

You may be able to loosen the two phillips head screws that hold the intake to the block after you get it running again,soak them with penetrant,and get it warmed up good,then take one at a time out and wire brush the threads and put never-seize on them...then if they ever need to be removed later on you can get them loose..
I put allen head bolts on a few Briggs like yours,they are easier to tighten & loosen..

I've gotten some pretty seized up rusty mufflers out by getting the engine hot un a load,then use a long pipe wrench or channel locks on the pipe part after loosening the lock ring (or cold chisel it off if it refuses to budge)...if it refuses to unscrew the last resort is to cut it off leaving about 1/4" sticking out of the block and cave the pipe inwards with a chisel ,then it will collapse enough to unscrew..
 

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Good ideas there... it’s Tough going on the pulsa-jets where the muffler is angled and can’t be unscrewed to gain access to the carb diaphragm next to it. -Looks as though this muffler was a straight one, however.
 

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Discussion Starter #13
I assume you dented in the muffler a tad...
Yes, the muffler was dented enough to use a screwdriver.

You may be able to loosen the two phillips head
screws that hold the intake to the block after you
get it running again,soak them with penetrant,and
get it warmed up good,then take one at a time out.
The Makita has a nominal 1,280 lb torque, and it freewheels. The flange and exhaust gasket are in the way of penetrating fluid reaching the bolt threads, and if there is galvanic corrosion then the head will be ruined. I have decided to relegate removal to the category of lost cause.

The carb was amazingly clean, no deposits to speak of in the bowl. After clearing the emulsion tube the engine fired up easily, and the shredder has been in active use.

The locking ring did not move until pounding with a pointed head punch on a corner cracked the ring. Drilling a hole on the opposite side let me break the ring in two for removal.

The 2 weeks of PBlaster and Silikroil when the ring was in place may not have achieved anything. It has now been a few days of easy access to the threads, and still no movement. The oval head locking vise grips get an excellent hold but so far all I have succeeded in doing is peel off shavings of steel when they slide.

Your 'last resort' will be my solution when if comes time to replace the muffler.

Thanks everyone for the support and ideas.
 

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Discussion Starter #15
If removal was a necessity I would give it a try but the incentive has dulled now that the carb has been cleaned and the engine is running.

The motor is way louder than I remembered it as being, and I would be more interested in removing the muffler if there was a significant decibel improvement to be gained by replacing it. So far the google consensus has been that B&S motors are loud, loud and loud, and the only real improvement comes from buying a Honda.

The note at Briggs and Stratton Replacement engine| Off-Topic Discussion forum | by 914Driver intrigued me because it says "Last winter my neighbor asked if I could rebuild the carb on his 8hp B&S TroyBuilt Rototiller. Sure. A month later he showed me the Honda OHV replacement he bought, I think ~$125. Seems to do everything the B&S did just fine."

If I could do such a swap for $125 I would not hesitate, because my Honda mower is not as loud as the B&S.

We are veering off on a tangent now that the primary problem is solved, all the way from how to remove the carb to a possible engine swap...
 

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I don’t find that engine especially loud, but I suppose compared to an OHV it would be. Possibly more so being a Honda. So short answer, yes indeed, loud x3.

I was going to suggest heating then quenching the pipe - but since it’s all working now, I agree with you completely.
Run it and enjoy the satisfaction of your carb work.
Cheers.
 
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