Briggs 5 hp idle issue or HELP my BRIGGS

[ReapersRide]

I have a 5 HP Briggs
Model #
136212
Type
1028 E1
Code
970818YB
I changed the fuel tank, repaired the choke and fuel pump diaphram.
I haven't opened the case up I am hoping that won't be needed.
My problem is the thing don't sound right.
Check out the videos see if you can tell me what I am not seeing
Thanks in advance
Terry
[video=youtube_share;xyjBtrwd1SY]https://youtu.be/xyjBtrwd1SY[/video]
[video=youtube_share;_PDfdzekjLA]https://youtu.be/_PDfdzekjLA[/video]

 

[buckeye]

Air leak around intake?

 

[Bignate123]

Kit a rebuild kit with all the gaskets and then try it

 

[Havasu Dave]

Your idle is set too low. The surging right now is because the governor is trying to compensate. Air vane or gear? I'd look at the gov adjustment, the idle adjustment, and the jet setting.

To set the jet, get the engine to operating speed and turn the jet to the right until it wants to quit, then back to the left until it wants to quit, then center it. Then adjust the idle.

The problem is not inside of the case.

 

[ReapersRide]

Although the sucking air theory makes sense I have all new gaskets on the carb after cleaning, also the idle was set up a full turn and half more.
And as for the mixture valve, I refer you to the exploded view of my carb. So I may have damaged the tank to carb gasket after 3 attempts at getting it right?
Thank you for the input.
Terry

 

[Dr. Shop Teacher]

Did you replace the gasket to the tank? If new, try loosening the carb and reseating the gasket (don't fully tighten each screw individually--tighten it as though you were torquing a head--gradually). In addition to Dave's correct observation, did you replace the fuel pick ups or at least clean the screens as best as you could? If the engine runs better with partial choke, then you've got an issue with the pick-up tubes contributing to the surging (especially if you had a really nasty tank on it before).

 

[chrisr]

I would back out the idle mixture screw about 1/8 at a time if this helps (if this smooths out with 1/8 turn out wait a minute and do another 1/8 turn out once you go to far out it should start running rough again and slowing down and just revert back to get the smoothest idle and maybe turn up the idle speed a little. Good luck, I have the same engine and runs great.

 

[ReapersRide]

[video=youtube_share;-UhMP5MziIw]https://youtu.be/-UhMP5MziIw[/video]
Yes the original tank was very bad, the secondary tank was rusted clean through.
It only had the outer edge.
Yes I did do a total carb cleaning the screens came clean.
Just dark shadows remained on the carburetor screen.
(Question) Should I use gasket sealer on the carb gasket?
I have disassembled the thing 3or 4 times so far.
I also checked all the carb screws and the 2 mounting bolt.
I am posting a third video

 

[ReapersRide]

Good though, however if you check my exploded view my engine has a Jet pilot.
No mixture screw in fact the only adjusting screw this 1997 engine has is an idle screw on the throttle butterfly
I wish I had a fuel mixture screw on it.

 

[ReapersRide]

Do you think it would help if I did a mock up?
1. Clean all of my Torque Converter components
2. Assemble them on a 2 by 8.
3. Attach a temporary throttle.
Then see how it does?

 

[Havasu Dave]

Do you think it would help if I did a mock up?
1. Clean all of my Torque Converter components No
2. Assemble them on a 2 by 8. Just clamp it to a table.
3. Attach a temporary throttle.
Then see how it does?

Your idle is set too low. The surging right now is because the governor is trying to compensate. Air vane or gear? I'd look at the gov adjustment, the idle adjustment, and the jet setting.

To set the jet, get the engine to operating speed and turn the jet to the right until it wants to quit, then back to the left until it wants to quit, then center it. Then adjust the idle.

The problem is not inside of the case.

So the idle is not set too low? Sure sounds like it to me at 5:30 AM on the computer speakers. Bolt it down, you cant do anything like that.

 

[chrisr]

Did you try adjusting the governor? Must be a year or model difference but I have three motors that look just like yours and they all have a idle adjustment screw. Good luck

 

[cruhr1]

I say it's the governor trying to compensate for the idle speed being too low. On one of your first videos you can see the butterfly being opened momentarily causing your engine to jerk and speed up briefly then it slows down and repeats. Why not unhook the governor and try it again? At least it will tell you if that's the cause and then you can make adjustments from there. And clamp it to a bench or something solid.

 

[Dr. Shop Teacher]

If you have a means to mount the engine on a secure bench, I'd do it. Hard to really diagnose with the engine hopping around. I don't think it's a fuel flow issue after seeing this latest video--it's idle as Dave said and it could be the screw setting or with your governor rod connections. But you can't mess with any of those until you can have two free hands.

 

[ReapersRide]

I am working on a stable mount for it today.
I totally agree with you there.
Terry

 

[ReapersRide]

[video=youtube_share;3RJUh68s7Pk]https://youtu.be/3RJUh68s7Pk[/video]
This short video has the Jet Pilot and it also shows the Idle screw being compressed due to being turned in.
Also I am posting 2 photos of a pair of 2 by 12 19 inches long I bolted together for runnability testing.
It works good can be clamped to a bench .
Doesn't move in grass and if I carpet the bottom it won't wander when used on pavement or concrete.
Tomorrow I will get video of it I ran out of daylight and gas
Terry

 

[ReapersRide]

Cruhr1 I will try that idea, I will need to figure a way to hold tension on the governor arm.
I am going through and doing everyone suggestions, spring is coming fast.
I would much rather be posting videos of my ridding some of my toys.
Instead I am posting this stuff.
Thanks for your help everyone just goes to show Old Mini Bike is a great resource.
Terry

 

[chrisr]

When you had the carb off the tank did you run a wire through the main jet and blow through the jet to clean it out? If not, this should be done. Adjust the governor per briggs recommendation. Generic instructions: Adjusting The Governor
The pilot jet (Idle mixture screw) about 1 to 1 1/2 turns out and back off the idle adjustment screw some then after it warms up a bit you should be able to adjust the idle speed and idle mixture screw for a smooth idle. Generic instructions: Adjusting the carburetor

 

[buckeye]

Good info right there.

 

[Havasu Dave]

I agree that you "should" have enough idle turned in.

As I've said a few times already, take a look at what you did before looking elsewhere.

That is indeed your needle valve on the video and the preliminary setting should be 1.5 turns out from lightly seated.

Rather than repeat what I and others have already said several times, the link below offers an exceptional guide and illustrations to your carburetor and what should be looked at. After that, it's your governor adjustment.

Disassembly, Cleaning and Repair of Briggs Tank-mounted Pulsa-jet Fixed-jet Small Well Carburetor