pt 425 robin engine pipes glowing

[washita]

anyone else notice the header pipes glowing bright orange on their motor? my brother in law noticed it while we were finishing up a project it was the usual thing 425 vs bcx23 changed plugs (looked fine/no unusual wear-color) new air filter pipes are still glowing (reminds me of a plugged catalytic convertor) think I will investigate muffler, motor only has 125 hrs on it, too early in my opinion to be acting this way

 

[Bob999]

Improperly set ignition timing can cause overheating of the exhaust system.

 

[SnowRidge]

anyone else notice the header pipes glowing bright orange on their motor? my brother in law noticed it while we were finishing up a project it was the usual thing 425 vs bcx23 changed plugs (looked fine/no unusual wear-color) new air filter pipes are still glowing (reminds me of a plugged catalytic convertor) think I will investigate muffler, motor only has 125 hrs on it, too early in my opinion to be acting this way

Under what lighting conditions? If it was dark out and the motor had just been run hard, it may not be abnormal. Air cooled engines have always run hot. Since the EPA mandates, they have run a lot hotter.

 

[Phils]

We all realize these things run lean and hot, and the hotter they get from running lean, the more the fuel heats and bubbles, and then the hotter it'll run.

Solve the lean run condition, solve the heat problem. An electric fuel pump and routing the fuel hose on the side opposite the exhaust didn't solve the problem, tho it helped.

The cooling fan on the side of the engine cover helped the most but I still need to let the PT cool down after hard work before shutting it off or it'll backfire/run on.

Phil

 

[washita]

cut open muffler today in my opinion the exit area of the muffler should be the same as the intake area there is no way this muffler could accomplish this after some crude math i now have as much exit volume as enter voume of air no noticeable difference in loudness and pipes only glow about 2-3 inches from motor, no backfire/run on when shutting off tempted to build custom dual exhaust

 

[BobRip]

cut open muffler today in my opinion the exit area of the muffler should be the same as the intake area there is no way this muffler could accomplish this after some crude math i now have as much exit volume as enter voume of air no noticeable difference in loudness and pipes only glow about 2-3 inches from motor, no backfire/run on when shutting off tempted to build custom dual exhaust

Please get detailed pictures of your work.

 

[SnowRidge]

Another Power Trac built muffler, I presume.

I junked mine and put a stock Kohler muffler on. Much better performance, no run on, and lower fuel consumption.

 

[washita]

[ATTACH]125890[/ATTACH] I apologize in advance if pictures are not sized correctly muffler project has been halted ( truck rearend has to be rebuilt first oops) I feel that the muffler still does not flow enough air volume cause there is exhaust exiting all openings will be working on a balanced air flow design after I fix the truck

 

[Rivco]

At the request of a Fellow member I am Re-posting a picture of the dual exhaust conversion I did on my PT 180.

Here's how I did it:
1- duplicated muffler cutout on other side of engine cover.
2- Fabricated new exhaust manifold flanges.
3- Welded a short peice of 1" black pipe nipple to flange.
4- Added 1" to 1 1/4" 90 degree elbow.
5- Added a 6" x 1 1/4" black pipe nipple to elbow.
6- Added a second 90 degree elbow just outside of the engine cover.
7- Added a short black pipe nipple and then welded it to a USA made 12" glasspack muffler.
8- Welded 1 SuperTrapp 3S tip to the ends of the 2 glasspacks. My PT 180 was 18 HP. so I ordered a total of 12 Diffuser disks with the two SuperTrapp tips. ( 6 per. side )

 

[washita]

I like that setup, next on the project list thanks for the parts breakdown