Briggs intek v twin starts hard

[Scrubcadet10]

first time for everything

I don't remember what the choke plate looks like on that engine but I have ones which had 2 holes in the choke plate. I blocked one of them which solved the excess cranking problem. Beware of running the starter too long, as it will cause over heating of winding reducing starting torque. I think B&S recommends no longer than 5 seconds followed by 10 seconds or so rest.

Walt Conner

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[Yardstar]

I remeber now I have a carb off a craftsman dyt4000 on my shelf i rebuilt just in case, its similar but has some differences like a different choke plate and the solenoid is mounted verticly instead of horizontaly, I will mount this different style carb as soon as i can and see what happens.

 

[Neo7]

My Carb has the brass plug.

I don't remember what the choke plate looks like on that engine but I have ones which had 2 holes in the choke plate. I blocked one of them which solved the excess cranking problem. Beware of running the starter too long, as it will cause over heating of winding reducing starting torque. I think B&S recommends no longer than 5 seconds followed by 10 seconds or so rest.

As always in life, there's no such think as "EVERYTHING! lol" ... So I've not tried blocking a hole on the choke plate (if there is one?) .... Would love to know if this mod alone does the trick?... But not how you would do this without something being sucked into the engine later?

I burnt out my first (B&S original) starter motor.. but it did take 3 years! but Chinese replacements are quite cheap. I was initially concerned about quality so I did quite a bit of cranking testing. What I discovered was you can crank the engine 3 times over about 30 seconds (with 3 second stops) and the starter motor gets much hotter than cranking it just once over 30 seconds. When you think about it the starter motor has to push past the initial compression stroke (and the flywheel inertia) each time, which is why it gets hotter.
And once the core (armature) gets hot (which can be checked with an infrared gun on the top and bottom bearings) it does not have a lot of surface area (just two small roller bearings) to dissipate its heat. So regardless of what B&S say it will take a lot longer than 10 seconds to cool. I actually worked my new starter motor to the point where it was smoking (that's the enamelled wire windings on the armature cooking) and the armature took about 3 minuets to cool down to a touchable 50 degC (122 degF).

Good luck Yardstar ;-)

 

[Yardstar]

My Carb has the brass plug.

As always in life, there's no such think as "EVERYTHING! lol" ... So I've not tried blocking a hole on the choke plate (if there is one?) .... Would love to know if this mod alone does the trick?... But not how you would do this without something being sucked into the engine later?

I burnt out my first (B&S original) starter motor.. but it did take 3 years! but Chinese replacements are quite cheap. I was initially concerned about quality so I did quite a bit of cranking testing. What I discovered was you can crank the engine 3 times over about 30 seconds (with 3 second stops) and the starter motor gets much hotter than cranking it just once over 30 seconds. When you think about it the starter motor has to push past the initial compression stroke (and the flywheel inertia) each time, which is why it gets hotter.
And once the core (armature) gets hot (which can be checked with an infrared gun on the top and bottom bearings) it does not have a lot of surface area (just two small roller bearings) to dissipate its heat. So regardless of what B&S say it will take a lot longer than 10 seconds to cool. I actually worked my new starter motor to the point where it was smoking (that's the enamelled wire windings on the armature cooking) and the armature took about 3 minuets to cool down to a touchable 50 degC (122 degF).

Good luck Yardstar ;-)

So the brass plug had no change? Man thats sad you figured out starter death rates before getting a solution, have you ever tested compression or did a leak down test on yours? Thats my next step after another carb i just cant get much shop time in on the weekend due to a barage of family activities.

 

[AVB]

I remeber now I have a carb off a craftsman dyt4000 on my shelf i rebuilt just in case, its similar but has some differences like a different choke plate and the solenoid is mounted verticly instead of horizontaly, I will mount this different style carb as soon as i can and see what happens.

That should be the steel fuel bowl instead of the cast aluminum version. Either way you need the correct main jets.

 

[Yardstar]

That should be the steel fuel bowl instead of the cast aluminum version. Either way you need the correct main jets.

Are the main jets different?

 

[AVB]

Are the main jets different?

Should be as the DYT4000 that I have serviceuses a 310000 series engine and you said you were working a 445977-1092-B1 which 13 cu in bigger and has a twin barrel carburetor. Even if the carburetor is the same style different engine use different jets. Plus on a twin it does matter one goes where as many twins have two different jets. The 445977 has a 791501 (1.13mm) left jet and a 791502 (1.16 mm) right jet. Now the same looking carburetor off a 446777-0264-E1 would 1.11mm left jet and a 1.14mm right jet. Now the 44P777-0027-G1 uses yet another set of jets. On top of that some the newer 44 series uses a single barrel carburetor.

 

[bertsmobile1]

It might be that the idle jet needs to be Natts knakker bigger .
This was a problem with the first batch of the plasic carbed 120000 series we got down here
Ther things that can cause these sorts f problems are very small leaks in the manifold & / or gaskets that are slightly obstructing air passages.

 

[Neo7]

So the brass plug had no change?

Brass plug is what I've always had ... except when I fitted the Chinese Carb (for a few days) which has a plastic/nylon plug. So either one was "no change"

Have you ever tested compression or did a leak down test on yours?

Compression test yes, many times ... But I can't see how a leak down issue would help with a starting problem? ... That's really an optimal performance thing.
Getting the valve timing just right does allow the engine to turnover without stopping on compression strokes. So that's important too.

Also I know it's a carburettor issue. Because I have another V-Twin motor (in another mower) and I swapped the twin barrel carb for the other mowers single barrel carb and the engine started easily.... I was tempted to convert the engine over to a single barrel carb ... but that would have been admitting defeat lol! ... Besides I learn a lot when things go wrong and I wouldn't trade that for the world!

 

[Yardstar]

Thanks again everyone, I believe I will start with the carbplate hole covering, even tho i put my hand over the intake while choking it with no luck, then ill try this other carb, then by then i will have an aftermarket o ring kit for the oem carb i will try if that doesnt help.