VIDEO: For the twin briggs experts - rough idle & low RPM

[Fordiesel69 271]

Is this flutter & uneven cyinder sound the symptom of a coil or carb issue. I know the governor hunting is a carb issue but what about the flutter in the exhaust?

Also the carb looked clean and I don;t see anythinng that can be adjusted or rebuilt? Just aquired this tractor so it is unkown how it was treated or maintained.

[Rooster 192]

Most of the video is pretty high idle so it is hard to tell, but sounds like it is mis-firing. Check plugs first.

I would NOT buy a new mag, the new ones are junk. Find a good used one.

On the carbs, chase all passages with pipe cleaners, Looking down from the top on the inside you will see some circuits with little brass jets pressed into them, dirt loves to hide in those!

[oldredrider 2,553]

I'm with Rooster on this one...sounds like a GOOD carb cleaning will fix what you have going on.

[Fordiesel69 271]

It does sound like it is misfiring, but I wonder if fuel delivery could cause this. During the winter on my 16HP the venturi would frost up, and would cause an uneven misfire like that.

I will try new plugs. I swapped them over from the 16hp and it did not fixt the problem.

[Callen 64]

Pull the tin off the heads and check for loose head bolts.

[Fordiesel69 271]

Head bolts = good.

Replaced sprak plugs.

Carb was dirty but all jets were nice and clean. Fuel pump diaphram was dirty and did not come clean but I did not want to rupture it by pressing. Also one intake gasket looked crappy so for now I used black RTV, the other was fine. Runs the same, that slight misfire and some governor hunting at low throttle / idle. Engine is still super powerful and just blows thru the thick grass. Just does not run unloaded very smooth.

Not sure what next.

[Rooster 192]

The governor hunting is either a mis-adjusted governor or a bad spring.

It can be internal governor problems, but I think I have seen that maybe twice in a hundred engines.

Most commonly the spring has just become weak.

Next step is air leaks, carb, intake, exhaust leaks can cause some problems as well.

Ignition timing , IE slipped flywheel, but that is uncommon in an engine that has been running awhile, more common in one recently had the flywheel removed.

Alot of guys do not understand that the flywheel key does not hold the flywheel in place, it simply aligns it. A properly installed flywheel will not move without a force extreme enough that you most likely did other damage...broken rods, etc!

You could also have a valve issue, though generally that gives more problems on top than bottom.

I did not notice, does it smoke when running poorly? Could be loading up on fuel as well...

[Fordiesel69 271]

No smoke at all. I will get some intake gaskets and a carb kit.

Is the carb kit any good, as in contain all the parts needed to make it like new? Like a techumseh the kit always comes with everything............

[Rooster 192]

USUALLY HAS EXTRA PARTS, LOL

[Rooster 192]

But before you spend any money, find the leak!

Start the engine, and using a good quality carb cleaner(I use gumout) short sprays around the base of carb, then around the intake flanges.

Listen for the engine speed to pick up...which is going to be hard to do with the governor acting up.....lol

[Fordiesel69 271]

Its not the gov acting up. If I hold the linkage firm the engine will just stall. So the gov senses the drop, then opens the throttle and corrects the problem. Over and over.

The carb needs redone anyways. I ripped one intake gasket and RTV'ed it which is not proper so it needs done as well.

[Rooster 192]

ahhh, gotcha

[Fordiesel69 271]

Ok guys, what do you think?

I put the new intake gaskets on, new carb mounting gasket, and a full carb kit. Runs 95% better but still just a tad of flutter at idle like the cylinders are not balanced. Both cylinders have equal compression with 3 psi less on the front.

No more governor hunting!!!!!!! I think i am going to leave it alone as it is. Unless someone suggests somthing else. It runs very acceptable now, im just OCD and want it perfect, but I may spend way too much time and never get to that point.

[Rooster 192]

Sounds pretty good to me....hard to tell over a computer, but definitely alot better!