plastic or rubber for vacuum gage

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yo

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I want to build a remote vacuum gauge set up. which would be better a stiff 1/8 plastic tube or 1/8 rubber hose ? I went to the auto parts store and ask for vacuum hose or plastic tubing that could be used off a fuel line. Was given 1/8 rubber hose but I tested it in gas before installing it on boat. :banghead: It wasn't the type of hose for fuel. Does anyone have a name for a product that I can use.
Thanks Mike
 
I want to build a remote vacuum gauge set up. which would be better a stiff 1/8 plastic tube or 1/8 rubber hose ? I went to the auto parts store and ask for vacuum hose or plastic tubing that could be used off a fuel line. Was given 1/8 rubber hose but I tested it in gas before installing it on boat. :banghead: It wasn't the type of hose for fuel. Does anyone have a name for a product that I can use.
Thanks Mike

You say you " tested it in gas". How did you conduct the test and what were the results?

I'm thinking if it's set up correctly, there won't be gas in the tubing anyway, just air. If you are going to vave a vacuum in the tubing and measure it, you need something that won't collapse or get smaller under a vacuum.
 
Use rubber USCG rated fuel line , its far thicker than thin tubing , is harder to kink and will not collapse.
 
Visit your local hydraulic supply house and look at nylon or poly tubing and push-in fittings. It is inexpensive, very reliable, darn near fool proof, and much smaller in diameter than clunky rubber crap. You can run 1/8 tubing like wire in the same runs.
 
What about copper tubing? That's what I used for mine.
 
Hi all that replied. Mr Rwidman I tested the rubber hose by putting the end in a can of gas, in a short time the end had swollen and was very soft. I think that it would have collapsed. Ben2go & Larrym the Tygon vacuum tubing sounds very good. Keith I'm trying to run this all the way to the fly bridge so copper would be very hard to install in that tight space. Rickb I'll check the hydraulic shops and look for the nylon or the poly tubing, being it is small feeding up to the fly bridge would be a big help.
thank again for the help.
mike
 
The connection between the fuel line Ts and the pilothouse-mounted vacuum gauges in the deFever I mentioned earlier was rubber tubing. I don't know what kind of tubing was used but I should be able to find out from the fellow who installed it. If I get an answer I'll let you know.
 
Vacuum lines

Since this tubing is tired directly into the fuel system it needs to meet the coastguard standards for fuel hose. If it does not you give up all the protection that the coastguard approved house in the rest of your fuel system provides in the event of a fire.

Another option is to use electrical sender tired directly to fuel line and wires to gauges at console.
 
I got an answer from the fellow who installed the system I described earlier. He said they used 1/4" white nylon tubing with compression fittings. This person, now retired, was for decades the head of the engineering department at what today is called Northern Lights/Lugger. FWIW......

PS-- He just added these comments:

1) Fuel hose would work but would be overkill.
2) I am always afraid of copper [tubing] because it may work-harden due to vibration and crack.
3) I think Racor offers a "kit" specifically for this type of installation.
 
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Citation please.

ABYC 24.5.7 All individual components of the fuel system, as installed in a boat, shall be capable of withstanding a 2 1/2 minute exposure to free burning fuel without leakage as required by Title 33 CFR, Section 183.590 and as required for individual components in H-24.

There is an exception for components located outside the engine room.
 
In my last post the reference was for gas fuel system, the reference for diesel is ABYC H-33.5.6 which reads almost the same including the exception.
 
ABYC 24.5.7 All individual components of the fuel system, as installed in a boat, shall be capable of withstanding a 2 1/2 minute exposure to free burning fuel without leakage as required by Title 33 CFR, Section 183.590 and as required for individual components in H-24.

There is an exception for components located outside the engine room.

Gasoline or diesel? I suspect the plastic bowls on my Racor filters would fail that test. The Racor restriction indicator might as well, it's plastic.
 
Greetings,
AYBC RATINGS ARE NOT STANDARDS!!!!!!!!!!!!!!!!!!! They are suggestions at best and NOT enforceable by any law. Now, coast Guard may have standards that ARE enforceable by law.
Standard (definition)...something used as a measure, norm, or model in comparative evaluations:
Citation for CG standards please.
 
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Greetings,
AYBC RATINGS ARE NOT STANDARDS!!!!!!!!!!!!!!!!!!! They are suggestions at best and NOT enforceable by any law. Now, coast Guard may have standards that ARE enforceable by law.
Standard (definition)...something used as a measure, norm, or model in comparative evaluations:
Citation for CG standards please.

To the contrary, they are definitely standards, ABYC standards. True they are not law but many insurance companies use these standards in their evaluations of insurability. Where applicable ABYC standards follow coastguard regulations. If you want to do further research on fuel systems you can start with federal Title 33 CFR, Section 183.590.

In any event if you are at all concerned with your safety and that of your passengers many off the ABYC standards are worth following, especially in fuel related systems.

The final decision is really up to the individual.

Enjoy your boating activities and be safe.
 
To the contrary, they are definitely standards, ABYC standards.

Unless ABYC advisories are incorporated into CG regulations "by reference" they are nothing more than guidelines for manufacturers and those who care to follow them.

That fire test thing is for fuel tanks, it has nothing to do with the rest of the system in any event.

A vacuum line is not a fuel line, it's not a vent line, it's not fill line. If you are really anal about it, run a copper line up to the fuel level in a full tank. That satisfies the fuel leakage requirements of 33CFR183.

These boats ain't larger passenger vessels, they aren't classed or inspected and most small boat surveyors don't know their buttock from a futtock.
 
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