Author Topic: Plunger exhaust leak  (Read 319 times)

Offline Drew Back

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Plunger exhaust leak
« on: 01.11. 2015 23:13 »
I noticed my left side head pipe is leaking at the head is there any type of sealant I could put in there to snug it up??

Offline duTch

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Re: Plunger exhaust leak
« Reply #1 on: 02.11. 2015 00:18 »

 There's probably some kind of goop out there, however;
    I'm not sure if the Iron heads have a slightly tapered port (like I think the Alloy heads do?), but might be worth checking the end of the pipe where it goes into the head and check its condition ie;
      Ones I've had were a bit of a sloppy fit (actually partly 'rounded' at the port ends), so I stretched it slightly to make it parallel and a touch bigger than the inside of the port, so when it's pushed in becomes a nice snug fit, but add a very slight taper (or file the hard corner off) at the very end, so it doesn't gouge the port material-
    Hope that makes sense...?
 To do it I used a bit of 1,3/8" x 1/16 wall tube should be a snug fit inside the 1,1/2".
  Cut some slots up the length of it a half inch or so and stuff it in....but you need to be able to get it out, so I had a washer the right size to put in first with a bolt through it....and maybe more...if I remember more, I'll let you know if need be...I' sure you just want a quick fix, but good luck *smile*

Started building in about 1977/8 a on average '52 A10 -built from bits 'n pieces never resto intended -maybe 'personalised'
Have a '74 850T Moto Guzzi since '92-best thing I ever bought doesn't need a kickstart 'cos it bump starts sooooooooo(mostly) easy

Online muskrat

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'51 A7 plunger, '57 A7SS now A10CR,  '83 CB1100F, 88 FXST .
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Online Angus

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Re: Plunger exhaust leak
« Reply #3 on: 02.11. 2015 09:09 »
Be careful what you use as I know something was used on the A7 exhausts, but I don't know what (some form of exhaust cement). Anyway I still can not get the dam things out. Its not been urgent yet and there have been other methods to do what I wanted, but there will come a time when I have to risk significant damage.
1961 A7 since 1976
1960 A10 Gold Flash Super Profile Bike
1958 Matchless G80 Project
1952 Norton Model 7 Plunger
1950 T100

Offline chaterlea25

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Re: Plunger exhaust leak
« Reply #4 on: 02.11. 2015 12:10 »
Hi All,
Would you believe that ordinary silicone sealant works well  for this *????* *????* *????*
If you want a really high temp sealant I can recommend high temp "Dirko"
My Ariel HT5 would always leak at the pushed in head to pipe joint no matter what type of exhaust goo I used
until I tried the Dirko  ;)

1961 Super Rocket
1963 RGS (ongoing)