Removing J-tubes

[Benyon]

When removing my J-tubes to fit my heat exchangers the threaded stud (...?) came out with the nut instead of the nut coming off alone from the front of the engine (gearbox end). Is there any reason I shouldn't reuse these like a bolt instead of a nut onto a thread?

I also bought a fitting kit (gaskets & clamps etc) from JK, and the clamps (heat exchanger to exhaust) came as two large diameter washers either side of a wire gauze all inside the clamp, however the gause and washers don't fit over the exhuast so I have had to remove these to fit the clamp, will this have any negative effects if I just use firegum to seal the two together withthe clamp?

Running out of time to get the van running for the Christmas meet on Sunday :evil:

 

[rob]

I also bought a fitting kit (gaskets & clamps etc) from JK, and the clamps (heat exchanger to exhaust) came as two large diameter washers either side of a wire gauze all inside the clamp, however the gause and washers don't fit over the exhuast so I have had to remove these to fit the clamp, will this have any negative effects if I just use firegum to seal the two together withthe clamp?

if you leave the gauze and washers out the clamp won,t seal properly as it needs these to compress onto, i don,t think fire gum would last very long before it was blowing.

 

[Clarkson46]

When removing my J-tubes to fit my heat exchangers the threaded stud (...?) came out with the nut instead of the nut coming off alone from the front of the engine (gearbox end). Is there any reason I shouldn't reuse these like a bolt instead of a nut onto a thread?

Running out of time to get the van running for the Christmas meet on Sunday :evil:

Do not use the stud like a bolt, the soft mag alloy was never intended to take the wear of a thread being screwed in or out repeatedly. You seriously run the risk of stripping the threads in the head. Either clean up the studs with a die having removed the nut and locktite them back in or use new studs.

 

[steve92]

hi andy. when i put my exhaust on it had a small flange on the end of it making up half the sandwich. the washer and gauze fitted over the heat exchanger pipe, and the clamp pulls the whole lot together something like this. apologies for the crap drawing!

as for the bolt problem, i kind of agree with clarkson.new stud/ cleaning up the old stud is the best option, but your not going to be constantly removing and fitting it.

 

[Clarkson46]

hi andy. when i put my exhaust on it had a small flange on the end of it making up half the sandwich. the washer and gauze fitted over the heat exchanger pipe, and the clamp pulls the whole lot together something like this. apologies for the crap drawing!

as for the bolt problem, i kind of agree with clarkson.new stud/ cleaning up the old stud is the best option, but your not going to be constantly removing and fitting it.

The risk is you will tighten up the bolt and the threads will strip. The stud will be static in the soft material and you can tighten down the nut to the correct torque without fear.

 

[Benyon]

Thanks all, and a great drawing Steve :wink: so you just used one of the washers and fit the gauze against the flanged end of the exhaust, I can do that!

I am down to GSF to pick up some new studs at lunchtime, how do you tighten them in? or will it tighten as I tighten the nut onto it?

Might be running on Sunday with just one heat exchanger...?

 

[steve92]

yeah i only used one washer,the flange on the exhaust acts as the other. put some exhaust sealing paste round the joint as well. when you run the engine it liquifies and seals the joint. you may be able to put the stud in by hand. as clarkson says, put some locktight on the end thats going in the head. if you cant screw it in by hand, you could put 2 nuts on the end of the stud lock them together, and spanner it carefully into the head.if you only get one heat exchanger on, it will be one more than we will have!!

 

[Benyon]

Got one exchanger on, still need to connect it to warm air pipe (just connected as a J-tube atm) but hopefully thats the easy bit, already had to do some 'persuading'. Hopefully I can do the other on Saturday for double the heating :lol:

 

[steve92]

nice one!