'89 Marathon 3PG Mid-Range Miss

loudgoldwing

Hey Gents,

Few weeks ago, my 3pg spun the nuts that hold the muffler and the head pipe together, and they separated on the 11th hole of my local course.

I screwed everything back together, but things seem to be really loud again, and I've also developed a hit-miss-hit-miss in my mid-range. It does clean out nicely and runs clean again when the speed eventually climbs to a high enough point.

Example: "Waaaaaaaaahhhhhh da-da-da-da-da-da-da-da-da WAAAAAHHHHH!!!"

My questions are:
1a) Is there supposed to be a gasket between the muffler pipe and the head pipe?

1b) If so, would the leak caused by losing this gasket not only make things loud, but screw with the exhaust flow enough to make the cart run nasty in just the mid range?

2) If the coil or the ignitor were shot, once it hit a miss-point in the rpm range, it wouldn't catch back up at a higher rpm, would it?

BGW

__________________
This advertising will not be shown in this way to registered members.
Register your free account today and become a member on Buggies Gone Wild Golf Cart Forum

dan161

Yes there is a gasket for where the exhaust bolts on to the motor. However I just recently took the gasket out and cleaned both surfaces really good and put back together without gasket. It's the quietist it's ever been now. I built stock car motors several times and am a firm believer that a gasket is just a fail point over time. Especially on exhaust.

ScooterMcTavish

Boy the midrange miss is a funny one.

It's like the fuel is lagging a little behind the carb opening, that it's a little too open before the fuel gets there.

loudgoldwing

These were EXACTLY the replies I was hoping for, thanks!

To have the timing and voltage be OK for start-up, then fall out of time as the revs increase, then jump back INTO time at top speed... I was really seeing $$$.

Your answer, however, tells me:
1) The low end is kinda lean, but still in the low range of OK. But as the rpm's pick up;

2) The mid-range is suffering from a lack of back pressure because of the small exhaust leak (way too lean). But then at high revs;

3) The small exhaust leak reaches terminal volume of airflow, and the wide open throttle just barely brings the mixture back into acceptable parameters.

redcloud

There is no gasket at the muffler pipe flange to head pipe ony at the head pipe ( manifold) to jug. You may want to check and see that the nuts are tight at the jug to head pipe (manifold).