Pipe coupler material

[Mike Byer]

I heat race an Andy 80 in an Insane cat, and I have a very short life out of my pipe coupler, I have run some of the orange from Andy and some of Dick's clear stuff and some of seaduer Jerry's hard delrin, and the aero brand isn't even worth mentioning. 4 heats is about all, and you had better change. the delrin holds up, but it gets hot and swells up and leaks. Sugestions welcome.

Mike Byer

 

[Don Ferrette]

Get some aluminum 5/32" tubing & wind it around the coupler 4 or 5 times. Make it so you can slip it on & off the coupler (but not too loose). Then run your water outlet from water jacket to one end of the tubing. Connect the other end of tubing to your water discharge line that used to connect to the water jacket. I watched a guy do this on his OPS motors a number of years back, it was the only way he could get his couplers to last more than a single heat.

FWIW- once I stopped adding castor oil to mixed fuels my coupler life doubled.... :blink:

 

[TimD]

FWIW- once I stopped adding castor oil to mixed fuels my coupler life doubled.... :blink:

Mike,

Do you overlap your pipe over the header? If not have someone machine up for you a thin sleeve to fit over the pipe and the header, and the coupler then goes over the top of it. That way the coupler is not exposed to exhaust directly.

Another alternative is the teflon couplers. I got some from Ron Byrd a while ago and I'm still on the 1st one.

Don,

That is because the castor is pulling the heat out of the motor. The castor isn't causing the failure - the heat is. Removing the castor reduces the heated oil in the pipe.

 

[Don Ferrette]

"Don,

That is because the castor is pulling the heat out of the motor. The castor isn't causing the failure - the heat is. Removing the castor reduces the heated oil in the pipe."

Yup, no castor equals lower exhaust temps. B)

 

[TimD]

And higher piston temps most likely - that heat must be somewhere :unsure: The damned things cool down too fast to get a temp gun reading of any relevance. Did you have to increase your water cooling after the switch?

 

[Don Ferrette]

And higher piston temps most likely - that heat must be somewhere :unsure:   The damned things cool down too fast to get a temp gun reading of any relevance. Did you have to increase your water cooling after the switch?

Nope & actually found the motors run a touch cooler with the newer synthetic oils. So far so good .......... B)

 

[TimD]

Wierd :blink:

Sorry for side tracking your thread Mike.

 

[Bob Morton]

I heat race an Andy 80 in an Insane cat, and I have a very short life out of my pipe coupler, I have run some of the orange from Andy and some of Dick's clear stuff and some of seaduer Jerry's hard delrin, and the aero brand isn't even worth mentioning. 4 heats is about all, and you had better change. the delrin holds up, but it gets hot and swells up and leaks. Sugestions welcome.Mike Byer

Mike,

If you spend a little time sanding down the header on your MAC.

Andys quit pipe will slip over it no more coupler problems. Works

for me. Hummm need to get a new header HU

Bob Morton B) B) B)

 

[Propwash]

B) HI Mike : Some time ago I had the same problem with an AC Nitro Cat running a K&B .82 . Coupler wouldn't last a day . I found a listing in the boat modeler mag for an exhaust coupler and shaft log which was produced by a company called ALPHA boater , I beleive the person making it was in Arizona ,It is a machined exhaust coulper with water cooling at each end . Both the header and the exhaust - tuned pipe slip inside the coupler which has two rings at each end , this still allows you to make adjustments in length . Since I have installed this coupler I have never had a failure of any kind . Just have to add an extra water pickup or put a y connector in your water line to feed water through each end and also put an extra water outlet in your hull . The coupler looks like a dumb bell . Hope this helps . Look back approx 6-7 years in the boat modeler mag for the ad . I don't have access to any right now because I am at work . Hope this helps , Geoff.

 

[Don Ferrette]

"I found a listing in the boat modeler mag for an exhaust coupler and shaft log which was produced by a company called ALPHA boater"

I've got one of those kickin' around here somewhere. The bad part is they were originally designed to fit the OPS headers & pipes (see a pattern here w/ OPS) & almost all others required machining of the pipe & header to fit & have good seal & were a bit heavy. By the time you bought the Alphaboater coupler, had your pipe & header machined you had over $100 in the set up & that was 8+ years ago. The $1.00 worth of aluminum tubing is both lightweight & super inexpensive.

 

[[email protected]]

WOW, this is a tough one. Someone suggested slipping the aluminum over the header adn the pipe. Many years back my friend did that with a soda can. He cut it with his buck knike put one inside the Aerotrend coupler and one outside. They'd last for a couple days of running which was better than the average of about 5 laps.

 

[Mike Byer]

thanks guys, I thought I might be in the same trouble as a scale boat with the tight fitting cowl and not much air flow thru it too, I have tried a bunch of different things, but I need to give the coiled tubing a try, thought I had seen the hour glass shaped water cooled couplers some where too. sliding the pipe over the header was an early fix, but broke a couple pipes with that. the delrin/teflon does good, but gets hot and lets the pipe move and rotate. wow what a hobby, kind of like my wife, rewarding and pleasurable sometimes, but a pain in the ass most of the time.

Mike

 

[mike]

Im using an aluminum machined clamp this year, & from the results so far its working very good, doesnt slip & change settings, doesnt burn up etc., have one on my 20 mono & my 67 rigger. the prerequisite is to have a close sliding fit between the pipe & header, (similar to the 67 cmb header & pipe.......) then the clamp goes on where the pipe & header slip together.

 

[Rules]

I heat race an Andy 80 in an Insane cat, and I have a very short life out of my pipe coupler, I have run some of the orange from Andy and some of Dick's clear stuff and some of seaduer Jerry's hard delrin, and the aero brand isn't even worth mentioning. 4 heats is about all, and you had better change. the delrin holds up, but it gets hot and swells up and leaks. Sugestions welcome.Mike Byer

Almost any heavy duty truck supply house will have "silicone hi-temp heater hose with reinforcing braid". They sell it by the foot. You will need to wash it real good on the inside with "Dawn" or anything that will remove the molding wax. It's the wax that burns, starts the coupler to erode on the inside. If the one you buy is too soft, then boil it for a bit to harden it. I bought the translucent clear stuff to include with my tuned pipes, all I needed was a water seal, cost me about $2.88 a foot. Many of the truck places have stuff similar to Prather red in 5-6 sizes.

John in Huntsville

 

[TimD]

sliding the pipe over the header was an early fix, but broke a couple pipes with that. the delrin/teflon does good, but gets hot and lets the pipe move and rotate.

Mike,

What sort of pipe mount are you using? Sounds like that could be an issue too!

Tim.

 

[Ron Olson]

Kinda on topic, kinda off. I got a shipment yesterday from Gary P. and found a sample of Octura's new coupler. Pretty nice, it looks like teflon with reinforcing threads running through it. Thin walled and flexible. On my next order, I'll have to get some.

 

[Mike Hughes]

One of the best coupler that I have used is the Super Coupler. Man those things last forever. I have only replace one so far. It was on my 7.5 mono. 7 or 8 years of running. Not bad. The only problem is they are not available anymore. I was selling them in the NW and when my stock got down to ten the last time, I called Rod and said send me a batch. He had decided it was not financially viable to buy a new roll and cut them up for packaging because there were quite a few more options since Jim Auguston started selling them back in the early 90. When Rod told me, I said to my self, These things are made of unoptanium and stopped selling them on the spot. The only time I have to open a new package is when I build a new boat. I am down to my last three. If any one is interested in getting a roll, Rod has the numbers. He can point you in the direction of the manufacture. All free of course. You will need to save your money for the roll. Not cheap. We use to sell a 2" piece with 2 zip ties for $12. I think the rolls are 500'. You can do the math. They only sell them in a roll. No cuts.

Mike

 

[Terry Keeley]

Ya that stuff is great, any idea what it is?

 

[RaceCraftBearings]

I have teflon couplers for 20's to 90's and this stuff lasts and lasts and lasts. I have them on all my boats but the Mac 67 has had one on it for at least 5 years now (same one) and I race all year long. Best $8.00 you can spend.

Ron

 

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I almost choked when I saw that picture of the coupler....LOL It looked like a Jimmy Cap w/a load in it..... :lol: :lol: