Looking to make a homemade cooling system pressure tester, need ideas

[natemoore]

Yesterday, after spending a couple weeks rebuilding my controller and hopefully successfully adjusting my shift cables and interrupter, I started the engine for the first time in about three weeks. Thanks to a Pertronix/Flame Thrower/new spark plug wire upgrade, it jumped to life and idled smoothly. However, I still got that fleeting, sweet smelling whiff of coolant when it fired up. Then the scentless steam started coming from around the #4 cylinder.

http://forums.iboats.com/showthread.php?t=515290

So, step one is going to be pressure testing the cooling system.

I think I have an extra radiator cap. I was thinking about soldering a barb to the cap (after removing the spring). But, before I re-invent the wheel, I'm perfectly willing to copy someone else's design.

Got anything to share?

 

[Bondo]

Re: Looking to make a homemade cooling system pressure tester, need ideas

Ayuh,.... Buy or rent a Stant cooling system pressure tester...

 

[stonyloam]

Re: Looking to make a homemade cooling system pressure tester, need ideas

Autozone will lend you one for free.

 

[natemoore]

Re: Looking to make a homemade cooling system pressure tester, need ideas

Ayuh,.... Buy or rent a Stant cooling system pressure tester...

Hey, that's no fun!

 

[natemoore]

Re: Looking to make a homemade cooling system pressure tester, need ideas

Autozone will lend you one for free.

Can you believe that both of Advance Auto's pressure testers were broken and leaking?:facepalm:

So that means a field expedient home made pressure test.

I disassembled a 20 psi radiator cap and decided I could use the cap, the brass disc, and the valve stem from an old popped inner tube of a dump cart. I got lucky because the diameter of the hole in the cap was the same as the diameter of the valve stem.

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I didn't use the silver disc.

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[natemoore]

Re: Looking to make a homemade cooling system pressure tester, need ideas

The valve stem fit nicely through the hole in the cap, but this doesn't really need to form a seal. I put the brass disc in between the cap and inner tube, orienting it the same way as it was originally (which I decided was opposite of the way I had it oriented here).

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[natemoore]

Re: Looking to make a homemade cooling system pressure tester, need ideas

I cleaned the inner tube and rubber disc with acetone and glued them together. I figured I need some extra thickness to make it tight.

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[natemoore]

Re: Looking to make a homemade cooling system pressure tester, need ideas

Some plumber left his gas line pressure tester at a jobsite. I found this in the grass by the house. There was no way to find the owner, so I kept it. I put together some bushings and nibbles from Lowes and put this all together.

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[natemoore]

Re: Looking to make a homemade cooling system pressure tester, need ideas

Here it is installed and pumped up. I put some Vasoline on the rubber disc to make sure it didn't deform when I put the cap on. I didn't go past the locking tabs on the reservoir neck, so that held it tightly in place.



I pumped it up to 15 psi and leak checked the tester itself. Had to redo one of the fittings, but now it doesn't leak.

Question: how long should I leave it on? It's going to be 20 degrees cooler at night, which will make the reading decrease, so I need to do this test when the outside temperature is consistent.

 

[natemoore]

Re: Looking to make a homemade cooling system pressure tester, need ideas

Anybody know why only one of my pictures is previewing as a thumbnail? Did them all the same.