Swagelok Compression Style Fuel Fittings

[asnowsquall]

I purchased some Brass 3/8 OD tubing-3/8 MPT fittings that come bored straight through so you don't have to drill them out. These will work well for the coolant to fuel line transittion at the T fittings. Should have gone with 1/2" MPT, but thats another story. Next time. The brand I went with is Swagelok as the price was decent at $3 ea. and we use them at work and they are a high quality fittings. The 1/2" MPT is $4.40. They also have them in SS and they are $9.60 for the 3/8 OD tubing-3/8" MPT and $11.60 for the 3/8 OD tubing-1/2" MPT. Some pictures of the fittings here , including the fitting from Home Depot that I was original thinking of drilling. You can locate a local distributor here. Chris, it looks like you have one only about 22 minutes away at PORTLAND VALVE & FITTING COMPANY
Dave

[rackley]

This brings up a question I have.. Does anyone know of someone who sells 3/4" barbed T's? I can assemble one out of a female T and three 3/4" barbed fittings but it's much larger and much more awkward than if I could find them pre-made. I've searched high and low and haven't been able to find anyone who sells these.

Thanks,
Ray

[canolafunola]

http://www.shipstore.com/ss/html/MLM/MLM33437.html

You can find these at just about any Auto parts store.

[rackley]

I'd question if the one on the web site could handle engine temps since it says it's FDA rated (which implies not for automobile anti-freeze) , but if they're at an auto pats store and made for 3/4" hose they better :-)

[cgoodwin]

McMaster carr # 91355k54 $8.00 Brass

[asnowsquall]

Another thought about using these fittings....

Your system is HIH running from your fuel pump which is at the fuel tank to your filter under the hood. So, you have a T fitting at each end of the HIH. Say after you get everything together and now you notice a leak at one of your T connectors. It's coolant and its coming from the barbed fitting and you need to pull the fitting off of the T fitting to reseal it and try it again. Here is the problem. You loosen the nut on the compression fitting but the Ferrule is clamped on tight to your fuel line. Basically you can't take apart the T connection because your fuel line is being held at both ends by the compression fittings. Really need a drawing here to help show what I'm talking about. Here is what I believe may be the solution to this problem. Use PTFE front and rear Ferrules instead of the Brass or SS that came with the fitting. These will not dig into the tubing and will make the connection reuseable. We have done this at work with compressed gas, but I don't remember doing on fluids. I'm going to try this on my WVO installation to see how it works. I think the worst case situation using the PTFE Ferrules is a small coolant leak as the fuel line really can't go anywhere. I'll see if I can come up with a drawing to make this a little clearer.
Actually I'll take pictures and use a program to draw on the pictures.

[cgoodwin]

Not a good situation and the problem with ferrules which are soft is that they leak when stress is placed on the fuel line. You could stop the leak you described with Green locktite "for preassembled parts" which penetrates and hardens.


Chirs

[asnowsquall]

Here are the plastic Ferrules. Someone else mentioned that they think greasecars uses o-rings which may be another idea. I think the ferrules have more surface area for sealing and plus they are designed for this. Again, the reason I'm trying this instead of the metal is to be able to reuse the connection. I'll let you know how it works out for me!

[rackley]

Interesting. Where did you pick those up from?

Another idea if you had a leaking hose ferrule would be to just slather some JB Weld on it. Maybe a bit of overkill, but it'd definitely stop the leak I've done it before with gasoline fuel fittings (NPT, not a ferrule, but should work for ferrule just fine) and it works awesome.

[canolafunola]

I hope the hose in the picture is not what you will be using in your conversion. It looks like polyethelene, not pex. It is too soft, the walls are too thin and it will not hold up to the heat.

Originally Posted by asnowsquall

Here are the plastic Ferrules. Someone else mentioned that they think greasecars uses o-rings which may be another idea. I think the ferrules have more surface area for sealing and plus they are designed for this. Again, the reason I'm trying this instead of the metal is to be able to reuse the connection. I'll let you know how it works out for me!