Hi, in a previous topic, I mentioned that I rebuilt 50 horse 1988 johnny that was misfiring. bare with me here...changed flywheel and stator and pack, checked timing. all ok, I did notice that there was a fair amount of fuel in the carb throat ( both), the reeds are fine. Since it was a vro unit, I changed it to a fuel pump mix unit.<br />the engine is a rebuild, so I mixed it to 30:1 for breakin. the carbs do not have a mix adjustment, but does have a port for an electic primer injection. it does hold the gas in the line till needed to prime. (I think).. my question is this.. could the new fuel pump which was rated heavy duty (vaccum type). be putting out to much fuel to by-pass the needle and seat? the sierra cat. calls for it but other larger engines seem to use the standard duty.. rated for up to 45 horse.. is the pressure the same? I understand it should be about 2 to 4 psi..is that for all vaccum type fuel pumps?.. this is a real brain teaser. When it idles, It misses out the exhaust sometimes, I rev it up and it misses and bogs .. when it does miss, it gives a puff of exhaust that could look like it may be rich, when coming down from a 3K rev, it will slow down and stall out.. any thoughts on carbs.. there is no mix adjustment and it is rebuilt to spec. <br />I am tired of spending money on educated guesses on my end..<br />feedback is appreciated on what I have to look for.. It's a simple engine.. can't seem to find it, unless it might be a leaking head gasket????<br />the the compression is 117psi in both cyl.. should it be more pointing to a compression leak? (has new rings and pistons and re-bore.<br />thanks<br />Stan
