2 Briggs V-Twin questions

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Mad Mackie

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Just did some research and here is what I've found.
All Intek, ELS twin cylinder engines are vertical shaft engines.
Viewing the engine from the cylinder heads/carb/intake, the left cylinder, which is closer to the flywheel, is cylinder #1.The right cylinder is #2.
As the carb is installed in a reversed position on these engines, viewing the carb from the side where the air comes into the carb, sets up the carb barrels in the opposite positions. Still viewing the carb from the incoming air side, the R/H barrel/high speed jet feeds #1 cylinder and the L/H barrel/high speed jet feeds #2 cylinder. Some Nikki carbs are marked as viewed from the incoming air side, the left is R and the right is L. This is due to the carb being installed in the reverse position.
With this in mind, the emulsion tube on the carb installs only in one position, the smaller jet is installed in the R/H hole of the emulsion tube and feeds #1 cylinder, and the L/H hole feeds #2 cylinder. Generally #1 cylinder is fed with the smaller sized jet.
The parts manual for your 446777-0316 engine is available on the B&S website and downloadable. 0316 is the type number of your engine, make sure that you find the correct type number applications in the parts manual.
You need to know the date code of your engine in order to find the correct part numbers of the jets for your engine as the jet part numbers change between date codes. Where the B&S parts manual for the Nikki carb says (Standard) (Left) (Nikki) this is the jet that feeds #1 cylinder on the engine. Similarly for the #2 cylinder.
 

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Ronno6

Ronno6

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Mad Mackie said:
Just did some research and here is what I've found.
All Intek, ELS twin cylinder engines are vertical shaft engines.
Viewing the engine from the cylinder heads/carb/intake, the left cylinder, which is closer to the flywheel, is cylinder #1.The right cylinder is #2.
As the carb is installed in a reversed position on these engines, viewing the carb from the side where the air comes into the carb, sets up the carb barrels in the opposite positions. Still viewing the carb from the incoming air side, the R/H barrel/high speed jet feeds #1 cylinder and the L/H barrel/high speed jet feeds #2 cylinder. Some Nikki carbs are marked as viewed from the incoming air side, the left is R and the right is L. This is due to the carb being installed in the reverse position.
With this in mind, the emulsion tube on the carb installs only in one position, the smaller jet is installed in the R/H hole of the emulsion tube and feeds #1 cylinder, and the L/H hole feeds #2 cylinder. Generally #1 cylinder is fed with the smaller sized jet.
The parts manual for your 446777-0316 engine is available on the B&S website and downloadable. 0316 is the type number of your engine, make sure that you find the correct type number applications in the parts manual.
You need to know the date code of your engine in order to find the correct part numbers of the jets for your engine as the jet part numbers change between date codes. Where the B&S parts manual for the Nikki carb says (Standard) (Left) (Nikki) this is the jet that feeds #1 cylinder on the engine. Similarly for the #2 cylinder.
Click to expand...

Thanks for your in depth response.

I have found your ground work to be true. From the operator's seat, the #1cyl is on the right, and agrees with the carb casting.

But, now confusion sets in, as every mechanic whom I asked said that the larger jet feeds the #1 (right) cyl.(Except the mechanic who
said the jets were both the same, and he'd been doing this for a long time....)

True, the emulsion tube only installs one way, but what is lacking in your description is the orientation of the carb when installing the jets.
When you say smaller jet in the R/H hole, do you mean R/H as indicated by the R/H designation on the top of the carb?

Again, logic indicates that, as the L/H or #2 cyl is farther from the fan, it may require a slightly richer mixture in order to be properly cooled.
However, this flies in the face of the info supplied by the 4 mechanics who described otherwise. Be that the case,
your instructions make sense, and the mechanics with whom I spoke all got it backwards, as well as this video:

https://www.bing.com/videos/search?...43E1F1410E483B2CD2F943E1F&fsscr=0&FORM=VDMCNL

Or, does the #1 cyl need a richer mix because the #2 cyl gets fresher air, and the #1 gets air that has been heated by the #2 cyl?
Back in my Yamaha V-twin days, the cyl receiving the fresher cooling air got the leaner mixture.

As it will be a few days til my jet O-rings arrive, I have time to be further confused.

I still want to know how the engine will run with the jets reversed................
 
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ILENGINE

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Mad Mackie said:
Just did some research and here is what I've found.
All Intek, ELS twin cylinder engines are vertical shaft engines.
Viewing the engine from the cylinder heads/carb/intake, the left cylinder, which is closer to the flywheel, is cylinder #1.The right cylinder is #2.
As the carb is installed in a reversed position on these engines, viewing the carb from the side where the air comes into the carb, sets up the carb barrels in the opposite positions. Still viewing the carb from the incoming air side, the R/H barrel/high speed jet feeds #1 cylinder and the L/H barrel/high speed jet feeds #2 cylinder. Some Nikki carbs are marked as viewed from the incoming air side, the left is R and the right is L. This is due to the carb being installed in the reverse position.
With this in mind, the emulsion tube on the carb installs only in one position, the smaller jet is installed in the R/H hole of the emulsion tube and feeds #1 cylinder, and the L/H hole feeds #2 cylinder. Generally #1 cylinder is fed with the smaller sized jet.
The parts manual for your 446777-0316 engine is available on the B&S website and downloadable. 0316 is the type number of your engine, make sure that you find the correct type number applications in the parts manual.
You need to know the date code of your engine in order to find the correct part numbers of the jets for your engine as the jet part numbers change between date codes. Where the B&S parts manual for the Nikki carb says (Standard) (Left) (Nikki) this is the jet that feeds #1 cylinder on the engine. Similarly for the #2 cylinder.
Click to expand...

Looks like we came to the same conclusion when I said the small jet feeds #1 cylinder. Which in the OP case would be the R side of his carb.
 
Ronno6

Ronno6

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ILENGINE said:
Looks like we came to the same conclusion when I said the small jet feeds #1 cylinder. Which in the OP case would be the R side of his carb.
Click to expand...

OK.

Is there documentation for this?

I have been able to squint at a pic of the L jet, which used to be a part# 699732, now 792296 and it is a #118.
That is larger than either of mine.
This being the case, I would have to believe that the R jet would be smaller........ but, I have not been able
to verify that in a pic.

Now, does that mean that my #111 and #114 jets are too small for some reason??

Do you know how poorly the engine will run with the jets reversed?
Will it be obvious?
 
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Mad Mackie

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I'm not sure if most folks would ever notice a difference in performance, but in time a lean condition would show up in the #2 cylinder if it had the smaller jet and this will increase combustion chamber temperatures possibly to a point of damaging the piston, rings and valves.
I have a older version of the Intek twin service manual and it only covers up to 5/99 model years and only the single main jet Nikki carb.
I suspect that the updated version which covers the 446700 series engines will show the newer Nikki double main jet carb.
With the emulsion tube installed on your carb and viewing the carb on the incoming air side, the R/H barrel feeds the L/H cylinder on the engine and this is #1 cylinder.
The engine as an assembly is viewed and identified with #1 cylinder to the left, #2 cylinder to the right and the intake/carb in the center. This views the carb from its rear and the left barrel feeds the left cylinder which is #1.
With the carb removed from the intake and viewed from the incoming air side, then the R/H barrel and jet feed the left hand cylinder.
This is indicated in my Vanguard service manual for the vertical shaft Vanguard engines.
I have ordered a new B&S Intek twin service manual which is P/N 273521. My current Intek manual is 273521-5/99 which is old. If you purchase a service manual make sure that the date is later than 5/99.
I have a 30 HP Briggs Commercial Turf engine on my Scag Tiger Cub and need the updated manual.
This was a repower on my Tiger Cub as the original 44P777 engine burned up #1 cylinder, maybe the jets got swapped although I never had the carb apart on this engine. It only had 70 PSI and serious blowby on #1 cylinder when a leakdown test was done. This engine had 472 hours on it and I decided to replace it rather than overhaul it.
 
Boobala

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WOW ......we gonna have a library here pretty soon.. !!!
more info.. I figure the P/N of the jet determines which side it's for ( R or L )
According to the attached part list RIGHT side is # 2 ( I CANNOT guarantee the accuracy of this ( its from Ereplacementparts.com ) ALSO these p/n's are random ... be sure to use YOUR numbers !!
but I've never had a problem with anything I ordered from them either !!

According to the attached video.. @ approx. ( 4:27 min ) it shows markings on the carb body for R & L ..

I think after all is said & done ..... there are at least a few folks who would like to see some Briggs Engineers acquire some severe bruising
about their face , neck, arms, & chest inflicted by a ball-bat .. and of course there would NO information as to who, what, where & when !!! :laughing::laughing:

.............JETS # 2.JPG ...............https://www.youtube.com/watch?v=FZBaIcC_43k
 
Ronno6

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Well, here's what I have found this morning:

The item 117 on the parts list is new # 792296, and it feeds the left cylinder. It is now a jet #118
And item 117A feeds the right cylinder, and it is a jet #114.
These were obtained from squinting at photos of parts on websites.
Or, if anybody has in stock and would care to confirm........

Of course, should B&S decide to confirm or deny,all would be revealed.
The parts pic does not show a line to the emulsion tube to show an installation path.
I wold have to conclude that the R/L designation would coincide with the carb nomenclature on the top,(?)

My jets are #114 and #111.

Maybe I need to update to the larger jets??

And, to FURTHER mess me up, the part #'s in the parts sheets are for engines AFTER my date code, with NO info for MY engine being provided.
They list afrer date code 04080300 and mine is 040103YG

Maybe I should just order a set and hope for the best?
 
Ronno6

Ronno6

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Mad Mackie said:
I'm not sure if most folks would ever notice a difference in performance, but in time a lean condition would show up in the #2 cylinder if it had the smaller jet and this will increase combustion chamber temperatures possibly to a point of damaging the piston, rings and valves.
I have a older version of the Intek twin service manual and it only covers up to 5/99 model years and only the single main jet Nikki carb.
I suspect that the updated version which covers the 446700 series engines will show the newer Nikki double main jet carb.
With the emulsion tube installed on your carb and viewing the carb on the incoming air side, the R/H barrel feeds the L/H cylinder on the engine and this is #1 cylinder.
The engine as an assembly is viewed and identified with #1 cylinder to the left, #2 cylinder to the right and the intake/carb in the center. This views the carb from its rear and the left barrel feeds the left cylinder which is #1.
With the carb removed from the intake and viewed from the incoming air side, then the R/H barrel and jet feed the left hand cylinder.
This is indicated in my Vanguard service manual for the vertical shaft Vanguard engines.
I have ordered a new B&S Intek twin service manual which is P/N 273521. My current Intek manual is 273521-5/99 which is old. If you purchase a service manual make sure that the date is later than 5/99.
I have a 30 HP Briggs Commercial Turf engine on my Scag Tiger Cub and need the updated manual.
This was a repower on my Tiger Cub as the original 44P777 engine burned up #1 cylinder, maybe the jets got swapped although I never had the carb apart on this engine. It only had 70 PSI and serious blowby on #1 cylinder when a leakdown test was done. This engine had 472 hours on it and I decided to replace it rather than overhaul it.
Click to expand...

Now you're really trying to mess me up......
My engine, when viewed from the front (valve covers and carb fuel inlet pointing towards me) shows the #1cyl, to the left, but the carb designation for that side is Right.

You indicate the possibility of a hot running #2 cyl.
That would indicate the fat jet on the #1 cyl being incorrect.

So, fat jet to #2 (right as viewed form valve covers/fuel inlet side?) is correct?

Jeez, my head is spinnin' 'round........
 
Ronno6

Ronno6

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NOW, we enter a NEW variable into the equation: DATE CODE.

The nomenclature for DIFFERENT jets is listed as 04080300

MY date code is 040103YG
The parts lists for MY date code indicate that I use 2 standard jets...........BOTH THE SAME !!

The 2 jets that fell out of my carb ARE different!

MAN, I wish these things hadn't fallen out..........
 
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ILENGINE

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I just got off the phone with my distributor tech support. and was told take the tube that the jets fit in. It has two small holes and two big holes. turn the piece so that the small holes face your chest, the big jet goes in the left side.
 
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