tweeter6216 Posted October 24, 2003 Posted October 24, 2003 The engine is a Briggs & Stratton 16HP horizontal twin. Model number 402700 Code # 0130 Type # 01. I have a compression of 60 lb/sq.in from the left piston and like 5 lb/sq.in in the right. This keeps the right piston from firing. Would this keep the whole motor from running more than 5 to 10 seconds? Would the right side having little compression fail to draw gas into the carb?
dirtsaver Posted October 24, 2003 Posted October 24, 2003 Jim I'm not an engine man but my two cents anyway. I think the low compression would prevent that cylinder from drawing fuel in, and also might not provide the required pressure to fire. As I understand the internal combustion principal, You need the proper mix of air and fuel, atomized to a vapor mist, compressed to a state that when ignited it explodes the pressure forces the piston down. Low compression could take away at least two of those needs. Larry If I'm off base someone please correct me.
Dadsy98 Posted October 25, 2003 Posted October 25, 2003 Jim, check for spark on the right side. Then, check the valves. Might have to pull the head on this one. No experience here on the Briggs twin. Consider treating the engine as two single cylinder engines. just a thought. Steve
MarkM1958 Posted October 25, 2003 Posted October 25, 2003 I'm with Steve on this one, check for spark, check your valves, 5 lbs is not enough to fire even with spark. 60 lbs is not real good either, did this engine run prior to 1 cylinder going down? I may be wrong but, I was always told a small block chevy needs at least 80 lbs. to fire. And all cylinders must be no greater or less than 10% of each other. I would assume it would be the same for a twin. The 1 cylinder may not have enough compression to drag the other piston. I don't know about the Briggs, my Kohler twin has removable jugs and that makes for new pistons and rings an easy hop up. Good Luck and keep posting,,,,
DaleC Posted October 25, 2003 Posted October 25, 2003 You are broken. I guess you realize that. You are going to have to fix the bougger. I know that is not what you want to hear but probably rings and seating the valves would fix it. I don't know what rings would cost but a set is about 45 for an old cast iron. I would thing they are probably about the same for the twin. So for around a 100 you could have a like new running engine. Keep us posted on what you find and how you fix it. Good Luck
DaleC Posted October 25, 2003 Posted October 25, 2003 One more thing, your motor is 40 cubic inches. You are looseing one cylinder and dragging another. So the carb can't work effciently and your HP is down to less than half of what you should have. I would hazard that your 16 is now a 6 HP. I would say that is the running problem.
patrician12 Posted October 25, 2003 Posted October 25, 2003 If the compression is 5 pds the cylinder push is going somewhere.If the intake valve is open or burnt it will push the mixture who knows where.If it is the exhaust it will fire into the exhaust and run.If the piston has a whole in it or broken rings blowby will result.However,all three conditions will result in the most important factor of all internal combustion engines that people overlook.Engine vacuum!In a multiple cylinder engine you can get away with falling vacuum because it becomes a smaller percentage per cylinder but 1,2,or 4 cylinder engines it is essential that all cylinders be equal.Everything and I mean everything about an engine can be figured out by its engine vacuum.No vacuum no run.
tweeter6216 Posted October 25, 2003 Author Posted October 25, 2003 The intake valve was a hair from seating properly. The compression problem is fixed. Both cylinders run fine when I could get the motor to start. Still cant get passed the fuel pump not working properly. The gas is gravity fed to pump. That is OK. The tractor runs for a few sec. by putting gas in the throat of the carb. i replaced everything in the pump and carb too. I have vacuum to the pump. I followed the manual to correctly install the kits. I just cant get by the fuel pump. The bowl of the carb never fills up. If i fill it, the motor runs till uses the gas in the bowl. ANY SOLUTIONS?
UCD Posted October 25, 2003 Posted October 25, 2003 Run the fuel line directly to the carb. Ifthe carb is higher than tank Hang a tank higher than the tank IF it runs replace the fuel pump.
tweeter6216 Posted October 25, 2003 Author Posted October 25, 2003 I did replace the fuel pump exactly haw the book shows to. I sued every piece in the kit, replaced old with new.
UCD Posted October 25, 2003 Posted October 25, 2003 Eliminate the pump to determine if it is the pump or the carb that is causeing the problem. If it runs with the pump out of the picture it is the pump that is bad if it doesn't run then you might have a carb problem.
tweeter6216 Posted October 25, 2003 Author Posted October 25, 2003 The motor runs when eliminating the pump. I replaced the pumps' guts,i dont know what else to do now. i had the whole carb apart and cleaned everything. I took the upper portion of the carb off (this includes the float) and cranked the tractor. Shouldn't the gas get pumped out that hole in the lower portion of the carb through the hole in the gasket and into the upper portion of the carb to the valve controled by the float?
tweeter6216 Posted October 25, 2003 Author Posted October 25, 2003 I'm thinking that the little flaps in the diaphram of the fuel pump are not working properly. I have them and the springs in like the manual shows.
MPH Posted October 25, 2003 Posted October 25, 2003 Put an electric fuel pump on it like us Onan owners do..MPH
tweeter6216 Posted October 29, 2003 Author Posted October 29, 2003 Am i going to have to get a NEW carburetor?
cranemech Posted October 29, 2003 Posted October 29, 2003 Evening All, Jim, I'm confused (not hard to do these days :D) If you bypassed the fuel pump by running a fuel line directly to your carb with the tank higher than the carb and the engine ran fine then I would think your carb was alright. Later, Chad
HubbardRA Posted October 30, 2003 Posted October 30, 2003 I know that on a Kohler pump, you can configure the check valve mechanism to reverse the flow in the pump, by rotating that part 180 degrees. In other words, swap the inlet and outlet. Is there a possibility that this could have been done on your pump accidentally?
tweeter6216 Posted October 31, 2003 Author Posted October 31, 2003 YES, the carb works but i did everything that i know of to fix the pump problem.
UCD Posted October 31, 2003 Posted October 31, 2003 Then replace the pump or put an electric pump on it. It sure sounds like the pump is bad.
tweeter6216 Posted October 31, 2003 Author Posted October 31, 2003 How would you go about replacing the vacuum pump with an electric pump?
Al Posted October 31, 2003 Posted October 31, 2003 Hi, check that you haven't interchanged the input and pulse lines on the pump. This type of thing happens, so if you happened to do so, you can't patent it. Good luck, Al Eden
MPH Posted November 1, 2003 Posted November 1, 2003 Get a puraltor pump 2-5lbpsi range from the likes of NAPA. Choose a solid mounting area close to gas tank, ground black lead, run red lead to pos side of coil{least thats where I chose to on my 4040}, install filter between pump and carb, run line to carb. Been almost 2 yrs, but I believe mine was around 35 bucks..Good luck.MPH
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