can i swap the exhaust port with the intake port?

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sexyvicta

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another option would be to cut that thing up and get somebody to plastic weld it back together to suit.

the guys who fix motorcycle fairings would be able to tell you if that is possible.

i just cant see why you would want to change the engine to suit that ****ty lawnmower intake lol. Make the intake fit the engine
 

Bluethunder3320

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yeah, its not plastic i think its aluminum.

i wish it was steel so i could just weld it.

might just need a bigger drill bit then i can make a manifold.
 

sideways

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Toystory, what I explained is that it's possible, just not easy.

If you simply turned the cam 180 it'd run just the same as any other engine(I'm meaning a standard engine, still breathing through the right ports). Turn the cam 180 then turn the crank one full revolution, yep that's right, the 2 dots are lined up. You need to "flip" the cam, just like JHen says. Newer Briggs have a Nylon cam profile pressed onto a steel shaft, you could press this off and press it back on the other other way. Other than that you'd need to get a custom cam made up.

Russ, I'l go Briggs hunting this weekend, see if I can make something work. I've got a few ideas that would make this a fair bit easier than what you guys are saying. ;)

Blue: You don't need a big drill bit, just use the closest(but still smaller) drill bit you have and then make it the right size with a file or a Dremel ect. :thumbsup:

Thanks

Hayden
 

Russ2251

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Newer Briggs have a Nylon cam profile pressed onto a steel shaft, you could press this off and press it back on the other other way.
What???
What will pressing out the steel shaft and re-pressing it in accomplish?
That's like turning a screw upside down and expecting the threads to be reversed.
Come on guys....please think!!! Quantum physics it ain't.
 

Bluethunder3320

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well i made a manifold and oil filler, even a crank case breather,

but as soon as i filled the engine with oil it was all over the floor.

the old breather, i didnt seal up right. :censored:

i sort of..... welded a quarter... over the hole..... and it must have warped.
 

Russ2251

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There is absolutely nothing wrong with being "wrong"
Of coarse not and I am the first to admit when I am.
If I cannot backup (with facts) what I post, then I do not post.

To do as Bluethunder3320 suggested is not possible.
Knocking the camshaft out by any amount of teeth/degrees (±) will degrade engine performance.
At the very most, he might be able to reverse engine direction (with camshaft "as is") which would then require a reworking of ignition system.
 

sideways

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What???
What will pressing out the steel shaft and re-pressing it in accomplish?
That's like turning a screw upside down and expecting the threads to be reversed.
Come on guys....please think!!! Quantum physics it ain't.

If you go and reread my post... Press the nylon profiles off the shaft, flip them around, then press them back on. This gives you the correct profile to breathe through the "wrong" ports.

Quantum physics it ain't, engineering it is.

My 2c is that anything automotive is possible with the right tools, and time.

I completely agree, anything is possible. :thumbsup:

Thanks

Hayden
 

JHen

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Of coarse not and I am the first to admit when I am.
If I cannot backup (with facts) what I post, then I do not post.

To do as Bluethunder3320 suggested is not possible.
Knocking the camshaft out by any amount of teeth/degrees (±) will degrade engine performance.
At the very most, he might be able to reverse engine direction (with camshaft "as is") which would then require a reworking of ignition system.

No, it would actually be pretty simple. Switch the carb and header, then just turn the engine the opposite way you have to now to start it.

However, this could be perilous for anything that is threaded on as it could potentially unscrew itself because of the way the crank would be turning.
 

Russ2251

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If you go and reread my post... Press the nylon profiles off the shaft, flip them around, then press them back on. This gives you the correct profile to breathe through the "wrong" ports.
Show me!!!
Will not work...EVER!!!
No matter how you turn it, it comes up the same way.
A new camshaft must be ground.
Also, camshaft and gear are 1 molded piece. Only the shaft is steel, unless you have something I have not yet seen. Even if the gear could be separated and reoriented, you would still have the same thing.
 

Russ2251

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Pic 1 is how camshaft appears after pulled from a 7hp B&S.
Note the lobes.
In this position the exhaust valve has closed and the intake valve is about to open.

Pic 2 is how camshaft appears after flipping. Imagine the cam gear is at the bottom of pic where it should be.

Can you see the problem? The two profiles are identical. That is, exhaust valve has closed and the intake valve is about to open.
 

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