whats inside a G14 muffler?

[Kellyoc]

here's my question I have a G14 golf cart. I bought it last week. it had a large amount of gas in the motor to the point that it was spewing out the tail pipe when it was running. I came on here a lot of people said it was a dirty carb which is a good basic tip but not very likely on a fuel system with a fuel pump. on a gravity feed system yes very likely. other people stated it could be a torn fuel pump diaphragm which on a old fuel pump is more on the lines of correct. one thing I never saw anyone mention. is the fuel cap. on a older cart that sits the fuel cap doesn't vent properly the tank pressurerizes and forces gas up the pickup thru the fuel pump and carb into the intake and down thru the rings. which is exactly what was wrong with my cart. after fixing this problem. I changed engine oil, air filter etc... got it running great went down the street for a quick blast of 14 mph lol it ran great as it got hotter it began to smoke the hotter it got the more it smoked to the point it looked like a wall of smoke. ok oil soaked muffler. then I noticed the sounds coming from the tail pipe would change a noticble change in sounds engine began to run poorly lose of power acceleration etc... are Yamaha mufflers packed with any kind of wadding or fiberglass or is it just chambers? the way it acts its wadding that is temporally restricting the exhaust and choking out the motor. anyone cut open one of these mufflers that can tell me exactly what is in there. if there is wadding even if it dries out 100% it may never be right again

[slonomo]

I'm not sure I've ever seen an engine spew fuel and still be able to run. I've seen cylinders fill up with fuel and not be able to crank over, hydrolock. On your cart the carburetor is responsible for shutting off the fuel flow. The float will rise with fuel level in the bowl then the needle plugs the seat and stops the flow. The fuel pressure on these carts is very low, say 2 psi or so. These carbs are designed to work with that kind of pressure. I'd be taking the carb apart and cleaning it and inspecting the float and needle.

As far as the muffler goes, yes it's possible it could be plugged with fuel. But you need to solve the fuel problem first. The fuel in the muffler will burn off or evaporate. Typically 4 stroke mufflers don't get plugged. But if this cart has sat outside for some time, it could be plugged with insect nests etc. I don't think it would be oil plugged, since this is typically a 2 stroke issue. It is possible that there is some type of fiberglass material inside the muffler. The one's I've seen cut open were mostly baffles though.

It's likely you need rings.

[Kellyoc]

when I first got the cart. I did pull the carb and clean it and make sure everything was ok. it was almost spotless inside very vine micro dust on bottom of bowl but I still broke it down and went threw the jets etc and clean properly. the motor was so full of gas oil that it was pumping oil out of the breather hose back into the airfilter housing and then sucking it into the carburetor and it was just barley running I had to have it floored to keep it running and it was like a small stream of liquid coming from the tailpipe. so I changed the oil, cleaned out airbox, cleaned carb, replaced spark plug. then like I mentioned when I went to add more gas I removed the cap and the tank was pressurized it was the cap that caused the problem new cap and no further issues in regards to the above mentioned. I started it up and it ran perfect started driving it around it began to smoke more and more as I drove to the point where it was like a wall of smoke but still ran fine. then what was odd was the sound out of the exhaust changed it became muffled one second then kind of a whistle it sounded like debri or something inside the muffler was passing thru the tailpipe and also while this happened it ran very poor lost power etc... got home was very hot under the seat. its like the muffler is clogged or as its drying out crap is clogging it. I took off the muffler it is heavy probably 40 pounds shook it didn't hear anything rattling around. im just thinking it has a packing that is totally saturated and once it got wet it went from light fluffy sound deadening material to more like a solid brick that is now restricting the exhaust flow. I have done 2 separate compression test both hot and cold both were 165+

[BamaG14]

Kelly the stock muffler does have fiberglass packing around a pipe which has holes all around it where the exhaust comes out.This muffler has a real small pipe for exhaust compared to the inlet. I saw on here where someone put a larger one on the outlet to give motor more breathing . I cut mine off and welded a larger pipe too just to see. That's how I saw the fiberglass surrounding the pipe inside..

I did this with my original muffler. I have Plowman's on now which looks just like the original but small pipe is cut off some.

[duramax]

Originally Posted by BamaG14

Kelly the stock muffler does have fiberglass packing around a pipe which has holes all around it where the exhaust comes out.This muffler has a real small pipe for exhaust compared to the inlet. I saw on here where someone put a larger one on the outlet to give motor more breathing . I cut mine off and welded a larger pipe too just to see. That's how I saw the fiberglass surrounding the pipe inside..

I did this with my original muffler. I have Plowman's on now which looks just like the original but small pipe is cut off some.

did you notice any power change with the plowmans exhaust? is it louder

[sho305]

If it got oil in it, yes it will burn out when it gets hot much like G1s do. It will make a wall of smoke that is fun when you are a kid. It will stink bad. However it should run ok just make sure you run it slow or whatever to let it cool off as the muffler will get red hot. It can plug G1 you had to shove a rod up the pipe and knock the carbon out sometimes, from the oil burning. Normally 4 cycles dont have this issue as they don't burn oil. 2 stroke the oil would collect in the huge cold muffler with golf use. If plugged it can hurt the exhaust valve in a 4 stroke with too much heat. Burning out the muffler is fine long as it does not get too hot under the hood and damage something there. G1 would stop after maybe 20 min of wot driving around then it was good for some time, I did it on them way back when. I drive them around slow for a while to let everything cool after it quit smoking, they had a huge muffler the width of the cart.

[BamaG14]

Duramax I didn't notice any power change . It is not any louder or quieter than the stock muffler. In fact they look the same ...for my cart anyway. Only thing for the exterior is the outlet pipe is cut off near the muffler where the stock has a long pipe and turns down toward the ground. Not sure what Plowman does to the inside if any at all . I just got his performance kit and muffler comes with it.

[slonomo]

Kelly, take your muffler and put it in a nice bed of hot coals in a fire pit. This is common for the G1 guys. It burns off all the oil residue inside the muffler. It might destroy the fiberglass insulation, but it should still work fine, might get a bit louder. When it's completely cooled off, shake it around, tap it all over with a rubber mallet to loosen the debris, and blow it out with compressed air until nothing comes out. Some guys have used a hose to rinse it clean. Either way, you just need to get all the dusty bits out of there.

This will tell you if it was your muffler causing the issue. If it solves the issue, you could always get a different muffler if it's too loud.

The other option is to make your own exhaust. Cut the flange off the OE muffler and weld up some pipe to any kind of muffler you wish. Since it's a 4 stroke it really doesn't matter how you do it, as long as you use pipe that is equal in diameter, not smaller.

[sho305]

You might also be able to take the muffler loose and run it to see if the engine is smoking, just as a test.