OzVMX Forum

Clubroom => Tech Talk => Topic started by: Ji Gantor on February 22, 2009, 03:09:21 pm

Title: How To Clean Your Header Pipe
Post by: Ji Gantor on February 22, 2009, 03:09:21 pm

1973 CZ400 exhaust system is made up of two sections.
There is a header pipe which fixes to the side of the cylinder and bends down under the engine, where it is spliced onto the expansion chamber by a female, male connection.

The header pipe being fixed to the cylinder receives most of the heat from the engine. This heat breaks down protective coatings like paint. No paint, no protection, hallow rust.

First check the pipe for cracks and deep rust pits.

Ji  

 

Title: Re: How To Clean Your Header Pipe
Post by: Ji Gantor on February 22, 2009, 03:12:19 pm

Next inspect the exhaust flange to see if it is scratched or dented.

Ji

Title: Re: How To Clean Your Header Pipe
Post by: Ji Gantor on February 22, 2009, 03:15:43 pm

This header pipe has a large carbon deposit. The narrowing of the entrance will restict the breathing of the engine and will result in power loss.

Ji

Title: Re: How To Clean Your Header Pipe
Post by: Ji Gantor on February 22, 2009, 03:18:05 pm

This is the perfect job for a air die grinder.
Clean all the surfaces with the wire brush attachment.
This will clean most of the scale off the surface so you can see any imperfection.

Ji

Title: Re: How To Clean Your Header Pipe
Post by: Ji Gantor on February 22, 2009, 03:23:27 pm

To smooth out all the rough spots and rust divots use the sand paper flap wheel.
These are really good at not taking to much metal off.

Ji

Title: Re: How To Clean Your Header Pipe
Post by: Ji Gantor on February 22, 2009, 03:25:32 pm

I have just started using this type of attachment.
It still removes metal but really flattens the surface almost like polishing.

Ji

Title: Re: How To Clean Your Header Pipe
Post by: Ji Gantor on February 22, 2009, 03:29:49 pm

After using each attachment in turn the header pipe starts to clean up nice.
All of those rust divots must be removed to prevent corrosion occurring under the new painted surface.
If the pipe is thin removing metal is not an option, sand blasting is the best solution in this case.


Ji

Title: Re: How To Clean Your Header Pipe
Post by: Ji Gantor on February 22, 2009, 03:32:56 pm

Getting close now.
It takes time but the end result will be worth it.

Ji

Title: Re: How To Clean Your Header Pipe
Post by: Ji Gantor on February 22, 2009, 03:35:21 pm

Now we can turn our attention to the entrance of the pipe and that carbon build up.
Using that sand paper flap wheel slowly eat away at the carbon.

Ji

Title: Re: How To Clean Your Header Pipe
Post by: Ji Gantor on February 22, 2009, 03:38:44 pm

The entrance to the pipe is now looking good. The engine can breath easy and produce its designed horse power. The smoother this section is the better the breathing and there should be less chance of such a thick carbon deposit in the future.


Ji  

Title: Re: How To Clean Your Header Pipe
Post by: VMX247 on February 22, 2009, 04:03:52 pm

Great stuff.love it  8) too easy  8)
This is better than the Sunday school I went to.  ;)  ;D
cheers Alison WA

Title: Re: How To Clean Your Header Pipe
Post by: Ji Gantor on February 22, 2009, 04:54:36 pm

Hi vmx247,
I am happy you liked this topic.
The header pipe now has its first coat of heat proof paint.

Ji

Title: Re: How To Clean Your Header Pipe
Post by: Ji Gantor on February 22, 2009, 05:53:50 pm

After waiting the required time for the first coat to dry the second coat of heat proof paint was applied.

Ji