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> Heat exchanger pressure test fixtures. Available to lend, Update. They work. One leak found
bdstone914
post Feb 1 2021, 07:16 PM
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I completed the fixtures for the 2.0L and the 1.7-1.8 type flanges. They work fine.
Apreaciate all of the input from others. I think the chance of blowing up a thick wall tube is very unlikely with low presure. I worry more about my air compressor tank blowing at 150 PSI.
I did find one leak and not where I expected one. It is where the pipe is welded to the flange which mounts to the head. It took several minutes to see pressure decay. I then placed each fixtue under water and found the leak. Looks like the PO did a "make it fit" by drilling out the hole on the boss that goes to the head. It is a very is a slight leak which did show at 60 PSI and may not have leak under normal use. See video.

If anyone wants to test their heat exchangers I will lend these out for the $10 cost of shipping. I have two sets. one for 2.0 and one for 1.7 and 1.8 pattern.

Heat exchanger pipes can develop cracks that can cause carbon monoxide poisoning.
I made a set of test plates to be able to pressurize the pipes and check for leaks. I used 1/2" aluminum remnants that cost about $8. I added tire stem valves to the small plates that will bolt to the cylinder head ends of the pipe. Another plate bolts to the muffler end of the heat exchanger flange. They are lined with 1/8 Neoprene rubber to seal. I have a bicycle pump with a built in pressure gauge I am going to used to pressurize both pipes. They should hold pressure for an extender time. At this time O just made a 2.0 style plate but have material to make one for the 1.7 & 1.8 pattern.
After I test the ones I have I can lend them is $8 USPS Priority mail shipping is paid both ways.
The first attempt used 1/16" cork/rubber as a gasket and they had slow leaks as there was not enough compression.


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JeffBowlsby
post Feb 1 2021, 11:16 PM
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Why not just make a plate for one end with a rubber gasket (therefore usable on both HEs) and fill with water to test? KISS
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barefoot
post Feb 2 2021, 07:33 AM
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QUOTE(JeffBowlsby @ Feb 2 2021, 12:16 AM) *

Why not just make a plate for one end with a rubber gasket (therefore usable on both HEs) and fill with water to test? KISS


That's what I did also, but having been involved with pressure testing at work, the air pressurized method would give me much more confidence. (IMG:style_emoticons/default/sunglasses.gif)
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jd74914
post Feb 2 2021, 08:40 AM
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QUOTE(barefoot @ Feb 2 2021, 08:33 AM) *

QUOTE(JeffBowlsby @ Feb 2 2021, 12:16 AM) *

Why not just make a plate for one end with a rubber gasket (therefore usable on both HEs) and fill with water to test? KISS


That's what I did also, but having been involved with pressure testing at work, the air pressurized method would give me much more confidence. (IMG:style_emoticons/default/sunglasses.gif)

Personally, as a B31.1/3 guy I would do what Bruce did except fill with water too. So hydrotest with air-over-water to pressurize. Safer than air-only from the stored energy perspective but better performance than looking for gross cracks through mass fluid leakage.
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bdstone914
post Feb 2 2021, 09:00 AM
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QUOTE(jd74914 @ Feb 2 2021, 08:40 AM) *

QUOTE(barefoot @ Feb 2 2021, 08:33 AM) *

QUOTE(JeffBowlsby @ Feb 2 2021, 12:16 AM) *

Why not just make a plate for one end with a rubber gasket (therefore usable on both HEs) and fill with water to test? KISS


That's what I did also, but having been involved with pressure testing at work, the air pressurized method would give me much more confidence. (IMG:style_emoticons/default/sunglasses.gif)

Personally, as a B31.1/3 guy I would do what Bruce did except fill with water too. So hydrotest with air-over-water to pressurize. Safer than air-only from the stored energy perspective but better performance than looking for gross cracks through mass fluid leakage.



What is a B31.1/3 ?
I would think that a leak would be detected if there was a drop in pressure over extended time.

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jd74914
post Feb 2 2021, 09:46 AM
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QUOTE(bdstone914 @ Feb 2 2021, 10:00 AM) *

QUOTE(jd74914 @ Feb 2 2021, 08:40 AM) *

Personally, as a B31.1/3 guy I would do what Bruce did except fill with water too. So hydrotest with air-over-water to pressurize. Safer than air-only from the stored energy perspective but better performance than looking for gross cracks through mass fluid leakage.

What is a B31.1/3 ?
I would think that a leak would be detected if there was a drop in pressure over extended time.

@Jd74914

If you look at Bill's link it explains-it's a piping/pressure vessel code.

You are still looking for a drop in pressure. The difference is that you have less air in the chamber so if there is a weak spot that ruptures there is less chance of metal flying. (IMG:style_emoticons/default/smile.gif)
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