Briggs 17hp wont start and stay running

bertsmobile1

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24,745
In my first reply I asked you a lot of questions because we need to know what you have done, so we can work out what might be wrong.
Your response to the valve gap question was
I thought that didn’t apply to this motor. So, I don’t know that one.
Well I would not have asked the quesion if it was not important to know the answer.
You did not say that you don't know what it is or how to measure it your response was you did niot think it mattered then promptly ignored it.

I even went to the effort of explaining it in a subsequent post and you still ignored it.

The you pulled the motor apat again with out being to to do it and pronounced everything was all right despite the fact that you claim to have no mechanical knowledge so how do you know everything is OK ?
Next post you are making more adjustments to god only knows what on the carburettor which will make absolutely no difference to fuel accumulating in the muffler which by the amount of cranking you did could have been no more than condensation, we don't know because we are here and you are there.

You have come to here because you are in way over your head and drowing.
We all understnd that and are quite willing to walk you through the job one bolt at a time if necessary.
However in order fr it to work you need to do what you are instructed to do, nothing more, nothing less.
Just carry out some basic insructions and if you do not understand how or why then ask.
Engine diagnosis is a SYSTEMATIC process you start with easily measurable things like valve lash, magneto coil clearences, even valve timing marks then go on to more difficult bits.
But you have to do what you are instructed to, nothing else or it just will not work and you have just as much chance of getting it working as if you tipped your tool box out and locked a couple of monkeys in with the mower overnight.

The carburettor is a good example.
The only thing that stops the fuel pouring out of the carb, running down the manifold filling up the cylinder then pouring into the muffler is the float valve. That is it, the float valve, nothing more nothing less and nothing to adjust.
no screws, no levers, no springs. Absolutely nothing other than the float valve .
SO if you are told it is the float valve your responce is "how do I check it" ? and definately not
I will check that, the float on the carb should be good. I bought a new one because the old one was doing just that
Obviously the carb is not good or it would not be leaking and if you did not know how to check it or fix it in the first instance how will you know what to do now ?
Floats rarely need to be replaced.
Float valves ( some times called needles ) do
And where possible the valve seat as well. but I don't think that carb has a replaceable seat, others will know for sure.
And if not replacable the seat needs to be cleaned and on some occasions a very light reface of the sealing edge.

Joining this forum will not do anything towards fixing your problems.
Carrying out the instructions you are given, to the letter, will.
If you don't know why, just ask we will be happy to explain. ( you might notice I actually tried to do that in my second responce )
Most of us like explaining why but most "customers" just want to get their engine running and don't seem to care about understanding what they are doing, they just want to mow their grass, yesterday.

There is no one here that gets their jollies by trying to belittle, humiliate or insult others, we are all here to help or to be helped.

As for the videos, stop trying to post them.
To a large extent they are a waste of your time making and our time watching.
A good large clear well focused well lit still image of the entire side of the engine where we can clearly see what is connected to where is 1000 times more beneficial than a dark fuzzy out of focus video .
So for instance a photo of the cam showing the timing marks would be good. some of them have more than 1 set of marks.
Another photo of the govenor & oil slinger ( paddle wheelie thing ) would be good.
A close up photo of the float valve would be great and if taken agaainst a medium grey or dull white surface it would be even better.
Then we can eliminate every possible cause of your troubles, one at a time till you are scooting around with a nice big smile on your dial.
The photos will also be handy for you to keep for refference because what is shown in the manual and what is on your engine sometimes look nothing like each other.
 

Daquiri_briggs

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Feb 15, 2016
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Berts and CO.



What I can answer now...

I replaced the float because the old one had gas(some liquid) in it. I will go get some pictures of the carburetor, but I will have to put it in a video format because this site still isn't letting me upload pictures. Using the old or new function. I will see what else I could do for pictures.


When I said I would check that, I was talking about the valve lash. I can check the gap to see if it is right, now that I understand what it is.

I took the engine back apart to make sure that the timing was right, and now I at least know the dots are lined up.


I shall return...
 

bertsmobile1

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24,745
Pictures are great.
On drop box is even better as we can magnify them till we can see what we need to.
The float needle looks good is it the original one ?
On that particular type of carb the float height is adjustable by carefully bending the brass tap the needle sits on.
You nearly always have to make an adjustment to compensate for differences in manufacture and the solder on yours looks pretty crook
I am not 100% on the actual height as I arely ever work on that motor, they are quite rare down here.
The exact metod will be in the manual that was in a previous link, If it does not make sense to you ask and we will guide you

Next if you have not already put the heads back on, do not do it till we are sure the valves have the correct clearences as you have to take the valves out to alter the gap.
I will start an arguement with this comment but I never reuse an old head gasket no matter how good it looks.
Too much work to save $ 30 if they give way
 

Daquiri_briggs

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Pictures are great.
On drop box is even better as we can magnify them till we can see what we need to.
The float needle looks good is it the original one ?
On that particular type of carb the float height is adjustable by carefully bending the brass tap the needle sits on.
You nearly always have to make an adjustment to compensate for differences in manufacture and the solder on yours looks pretty crook
I am not 100% on the actual height as I arely ever work on that motor, they are quite rare down here.
The exact metod will be in the manual that was in a previous link, If it does not make sense to you ask and we will guide you

Next if you have not already put the heads back on, do not do it till we are sure the valves have the correct clearences as you have to take the valves out to alter the gap.
I will start an arguement with this comment but I never reuse an old head gasket no matter how good it looks.
Too much work to save $ 30 if they give way

I will work on getting that adjusted.The float needle is new, but I do have the old one... I think unless I threw it away. For the Carb, I bought a gasket and "parts" replacement for the carb. Out of the package I replaced the needle in the picture and the two screws with springs on them(idle and gas mixture??).

I have already put the heads back on, but all the gaskets are new. I just bought them, so they have only been used while I was trying to crank it haha.

All parts new and old can be found in these pictures.
https://www.dropbox.com/sc/veu1rf74n8vrjze/AAD7hPGiCq0ikyP4iexoDoQCa
 

bertsmobile1

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24,745
well that explains why the needle looked so good.
Read the manual about float height and be very gentle.
A very small amount of adjustment makes a very big difference and running with a low float can cause lean running , overheating and ultimately the big bang.
Have you had a chance to measure the valves yet ?
 

Daquiri_briggs

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Hey Guys,

I have been super busy with work and not had much time. I am going outside now to see if I can check the gap quickly, if not I will have to get to it on Friday or tomorrow.

"running with a low float" = The float hanging down to low? or The float not hanging low enough?
 
Last edited:

Daquiri_briggs

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Alright, so I believe this is what y'all are looking for? If not let me know.


I think it is not right at all, I tried to use the gauge to slide it in between the two "rods" and it wouldnt fit at all. So either it is not right, or I was doing something wrong. It is like this on both sides. I am headed to youtube to make sure I was doing my part right, but I thought I would get this up if people had immediate feedback.

Album is here
https://www.dropbox.com/sc/8suwwe2ltxw45t4/AADHVUAGnASz5-MvQLCeKv_Pa
 

ILENGINE

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Looked at your pictures, and you are correct the float is suppose to be parallel with the gasket. So with the upper part of the carb upside down the side opposite the pin should be level with the end with the pin, or relatively close.

You are check the valves correctly, just make sure that what ever side you are working on that both valves are closed, and then go a little past TDC on the piston. You will need to remove the springs from the valves and remove them, and file or grind off the bottom of the valve stem and keep retrying until you get the correct gap when checked with the proper gauge.
 
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