Exhaust Couplers

[chriscrash]

What are you all using for exhaust couplers? I am using Prather couplers on my Mac motor sport 40, but they keep splitting. I have had this happen last year, but it was due to a sharp exhaust header end. Now the are splitting in the vertical (front to back) direction. Off the water, the Mac is 100 degrees, and the coupler is around 280 degrees. The coupler ballons out and almost goes clear in color, from the normal pink.

I can make it through a full run, but don't want to constantly replace.

Any suggestions?

Thanks again for everyone's help in advance.

Chris

 

[Lay26]

you can do one of two things 1 water cool your exshaust header or contact MIke Hughes and get some super coupler(that stuff is GREAT!)

 

[Bob Morton]

What are you all using for exhaust couplers? I am using Prather couplers on my Mac motor sport 40, but they keep splitting. I have had this happen last year, but it was due to a sharp exhaust header end. Now the are splitting in the vertical (front to back) direction. Off the water, the Mac is 100 degrees, and the coupler is around 280 degrees. The coupler ballons out and almost goes clear in color, from the normal pink.

I can make it through a full run, but don't want to constantly replace.

Any suggestions?

Thanks again for everyone's help in advance.

Chris

Hi Chris,

The best solution is to slip the pipe over the header. You will never burn your coupler.

Bob Morton

 

[Brent Wyble]

Seaducer also sells the white super coupler. Bit of a pain in the ass to put them on but once it is it's great.

 

[Don Ferrette]

First off Chris how much of a gap between header & pipe??? :unsure:

 

[chriscrash]

about 1/8". I can't put the header in the pipe, they are the same size. While I've got you Don, If I shorten the pipe, what will that do in theory? More torque or Rpm. If it is shortened, richen or lean needle? Right now it is 9 7/8" with the Mac and AB parabolic, x450 prop

 

[Don Ferrette]

about 1/8". I can't put the header in the pipe, they are the same size. While I've got you Don, If I shorten the pipe, what will that do in theory? More torque or Rpm. If it is shortened, richen or lean needle? Right now it is 9 7/8" with the Mac and AB parabolic, x450 prop

Will give more rpm, you should be able to get pipe to between 9 1/2" & 9 3/4". Get a higher quality coupler if gap is only 1/8", I've not seen those Prather pieces last for squat.

 

[WikiWiki1]

Where can a guy buy this "super white coulper" material. I don't see it on Seaducer's website.

Mike please chime in if you have it available.

Thanks, Brent

 

[Scott Norris]

Just call em.

 

[boaterbill]

Just call em.

I've got four of them, don't remember what I paid for them or what they are worth. Make me an offer.

Bill

 

[Mike Hughes]

I have the black tubing that is called Super Couplers. This is the stuff Jim Auguston found back in the early 90's. If you want that, I can provide. I think the other white stuff they are refering to may be teflon couplers. Not sure.

Mike

 

[Bob Morton]

about 1/8". I can't put the header in the pipe, they are the same size. While I've got you Don, If I shorten the pipe, what will that do in theory? More torque or Rpm. If it is shortened, richen or lean needle? Right now it is 9 7/8" with the Mac and AB parabolic, x450 prop

Hi Chris,

With some effort and time. You can sand down the Mac hearder. Then the pipe will slip over the header.

Take the time It will be a big pay off. No more blown couplers.

Bob

 

[boaterbill]

I have the black tubing that is called Super Couplers. This is the stuff Jim Auguston found back in the early 90's. If you want that, I can provide. I think the other white stuff they are refering to may be teflon couplers. Not sure.

Mike

Not sure Mike, I know you have to heat them to constric them on the pipe & header.. I bough them at the Internats (namba) when they had it in CO. They are solid white.

Don't like them because onece they are on, they are on, don't remember how to move the pipe if you have to. Heat them again?

Bill

 

[Mike Hughes]

Thats them. You can machine that stuff to fit any application. You have to heat it up to get it on or off.

Mike

 

[Duck899]

Thats them. You can machine that stuff to fit any application. You have to heat it up to get it on or off.

Mike

A Monokote style of heat gun works well for installing this material and removal. Removal is a bear though, so get the length right first by using a standard coupler or know what length you need to run. The white teflon material should last for quite a while. I ran my scale and 67 rigger all season on the one coupler and intend to carry on with the same couplers this season. Sure beats waiting for a coupler to blow on the last lap in the final heat.....

 

[Don Ferrette]

Thats them. You can machine that stuff to fit any application. You have to heat it up to get it on or off.

Mike

A Monokote style of heat gun works well for installing this material and removal. Removal is a bear though, so get the length right first by using a standard coupler or know what length you need to run. The white teflon material should last for quite a while. I ran my scale and 67 rigger all season on the one coupler and intend to carry on with the same couplers this season. Sure beats waiting for a coupler to blow on the last lap in the final heat.....

It's faster & easier if you use a propane torch. Heat teflon just until it starts to get a glossy haze then install it & let it cool naturally. Make sure you lightly sand (taper) the square edges of the end of pipe & header & use some 80 grit paper to rough up the area the coupler will sit. One VERY important thing to remember, do the coupler installation in a WELL ventilated area, preferrably outdoors, very toxic fumes when heated!!!

 

[slsova]

Seaducer also sells the white super coupler. Bit of a pain in the ass to put them on but once it is it's great.

 

[Glenn 787]

use some 80 grit paper to rough up the area the coupler will sit

Missed this step. Maybe this is why my coupler has a tendency to slide down my header. I finally filled the gap on the header with a regular coupler to stop it.

 

[P THOMAS]

use some 80 grit paper to rough up the area the coupler will sit

Missed this step. Maybe this is why my coupler has a tendency to slide down my header. I finally filled the gap on the header with a regular coupler to stop it.

YOU can make those hard white teflon couplers eaisier to work with by using a wire brush wheel mounted in a drill press or drill. hold the pipes header at an angle to get a screw like pattern on your pipes header.

Heat up the teflon coupler and press in the pipe header, after it cools the header can be screwed in and out of the coupler to adjust the length and it will not slip. You still need to mount the stinger of your pipe, dont trust the header coupler to hold the pipe lenght.

 

[boaterbill]

use some 80 grit paper to rough up the area the coupler will sit

Missed this step. Maybe this is why my coupler has a tendency to slide down my header. I finally filled the gap on the header with a regular coupler to stop it.

YOU can make those hard white teflon couplers eaisier to work with by using a wire brush wheel mounted in a drill press or drill. hold the pipes header at an angle to get a screw like pattern on your pipes header.

Heat up the teflon coupler and press in the pipe header, after it cools the header can be screwed in and out of the coupler to adjust the length and it will not slip. You still need to mount the stinger of your pipe, dont trust the header coupler to hold the pipe lenght.

You can make the coupler hold the pipe lenght if you coat the coupler inside with vaseline.

Tou can also get a sheet of alum or brass cut to fit wrap it inside the coupler, won't blow out, coat it with vaseline also.

Bill