Briggs 35 hp vanguard
HI, I am new on here.
I have a new B&S 35hp vanguard engine that I bought new back in March to fit to a hovercraft I was building.
I have had 2 problems with this engine, the first one was a valve pushrod adjuster came undone on the left cylinder inlet valve after less than an hours running. Luckily nothing got damaged on that side.
The above happened while I was trying to sort out the other problem with the engine.
The engine only runs on the right hand cylinder now & again.
I have replaced both coils & also rewired the coils to a double pole kill switch, so I could eliminate the coil diodes, as I know of several people that has had trouble with them. Initially the diodes were left in the circuit until I replaced the coils.
Problem still persisted.
Next I have checked valve clearances.
I have replaced spark plugs
I have stripped the carb down 3 times & blown out all the jets with compressed air.
This engine has only had approx 3 hours running & all of that has been spent trying to get it running properly. I am beginning to think these B&S vangaurd engines are a pile of *rap & I should of bought a Kholer or Kawasaki.
I am reluctant to send the engine back under warranty as I would have to remove it from the hovercraft, then transport the engine 300 miles one way (600 round trip). Then have to go & collect the engine another 600 miles + all the time & wear & tear on my car, then have to spend several hours replacing the engine & setting up all the pulleys etc again.
I have put a video on YouTube of the bag of nails running. The problem is always on the right hand cylinder, I even swapped the jets in the carb from right to left & problem stayed on the right. I have done a compression test & both cylinders were 125 lbs sq inch at cranking speed. ( I earthed the plugs to the engine lifting eyes so not to mess up the coils)
The fuel is clean & fresh, I put the fuel tank above the pump to eliminate it being a pump problem.
When the engine does get to 3000 RPM it sounds fine, but it rarely gets past 2400 as it is only firing on the left side.
I am beginning to think that I either have a valve problem or even valve timing is out slightly on the right side.
I am reluctant to remove the head to find out, but to take this engine back to Briggs is going to cost me several hundred pounds so probably cheaper to do it my self.
I have spent nearly 30 years working on cars in the motor trade, so fully capable of carrying ou the above.
here is a link to the engine running. The video has not been cut.
Any suggestions as to what could be the problem with this engine much appreciated.