The Stovebolt Site Forums The Shop Area General Truck Talk Basic fuel line options?

Hi. I have some basic questions regarding fuel line options. I want to replace and reroute the fuel line in my '61, and probably replace and reroute part of them in an '84 GMC truck as well.

I'm not a fan of rubber hoses and hose clamps in the engine compartment. And I also don't like the fuel line anywhere near the belts, fan blades and valve covers. (I could tell you a very fiery fire story that happened to '72 VW Super Beetle I once had - before it burned to the ground.)

Any how, I'd like to change the fuel lines and reroute them along the cowl area. Someone mentioned some flexible braided stuff that sounded interesting, but I'm wondering what type of fittings I could use. And are there adapters to go from the carb inlet to a special fitting. Summit Racing (and others I'm sure) have something called an AN fitting. Are these good? Would I need special crimpers to make my own hoses? And how about adapters to go from AN to hose to accomodate regualr type fuel filters if needed? And one more question, what size should I get? I would need to hook it to the fuel sending unit on the tank. I guess there's adapters for that as well.

What would you guys sugggest, and maybe pics of things you've done to modify your OEM fuel delivery system would be great.

Thanks for all your help!!

Use what Chevy did on millions of vehicles for probably billions of miles, trouble-free- - - - - -double-flared steel lines. If you must re-route them to accomodate some imaginary phobia, go ahead, but it will be a total waste of time and money. If the lines are mounted to the firewall, it will be necessary to install flex lines between the cab and the engine to accomodate motor mount movement.
Jerry

I agree GM did a much better job of building the fuel line than VW did. It might not be necessary, but I need to change out the lines anyway. So, I figured while at it maybe I could improve on the design a bit.

I'm okay with the steel line, I would just prefer not have the rubber hose line on top of the engine. I was thinking flex would be better. Thanks for the tip about using the flex line to absorb motor mount movement. Hadn't thought of that. :-)

NHRA and other racing association prohibit fuel lines mounted to firewalls. They prefer them not anywhere near the firewall if possible. I know its not a race car, but they are a pretty good gauge to go off of for safe and reliable vehicles.

What ever you decide, you must use a flexible line from the frame to the engine, and that would include from frame to firewall if you choose to go that way. Steel braided line if more then safe enough for the job, and yes you can make the lines yourself.

I must agree with the others, its a wasted effort the re-engineer something that works so well for so many years. Best advice is to replace whats there with new steel and for peace of mind, steel braided flex hose.

Joe

Thanks for more input. I won't claim to understand WHY it wouldn't be safer to mount on the firewall, but I will admit that the NHRA, GM engineers, and you guys have far more experience than me in these matters. That's why I'm here ... to learn ... and get ideas. :-)

So, if I run the stock OEM replacement fuel lines to the front of the engine, what do I need to adapt it to the steel braided flex line? And what size? They list AN6, -8, -10, etc...

And Joe, that is a KEWL looking truck you've got in the gallery. I can't wait to work a bit on my '37. Maybe mow and weed-whack around it a bit more to show it off. LOL Wish it looked like yours... But even parked and rusty they are very good-looking trucks!

Thanks for the help Jerry and Joe

"AN" lines are sized in 16th's of an inch, for instance, a #6 AN line would be 6/16", or the same size as 3/8" steel gas line. Since practically all the stovebolt gas lines I know of are 5/16", you would need a #5 AN flex line with the stainless steel braided reinforcement from the fuel pump inlet to the frame, where it would attach to the steel line back to the gas tank. Since the tank is solid-mounted, a flex line from the frame to the tank outlet would probably be a bit of overkill. The regular gas line routing from the pump to the carburetor goes just ahead of the valve cover, but it's bracketed solidly and shouldn't have any problems. If you use a stock-type glass bowl fuel filter at the carburetor inlet, you wouldn't even have the short rubber hoses and screw clamps to deal with that are usually used to attach an inline filter. The original-equipment AC strainer/filter with the ceramic insert and a glass sediment bowl was mounted directly to the carburetor inlet, and the gas line was attached to the filter with an inverted flare nut.
Jerry

I searched around for the filter type you're describing. Is this it? http://secure.oldchevytrucks.com/CA...LET-AND-GMC-1934-1962/productinfo/ME668/ I've never seen one like it before. It would work famously! Thanks also for deciphering the "AN" sizes.

That's it, but search E-Pay for an original-equipment part. Sometimes some real bargains show up, and things like the cork gasket and the porous ceramic (not paper) filter element is still available.

Check this one out- - - -it's an original:

http://cgi.ebay.com/ebaymotors/OLD-...arts_Accessories&hash=item2a1212547c

Jerry

Thanks, HotRod. If you know of where to find the ceramic filter, please let me know. I found where I can get the gasket. I like this option.

I used copper line. Sure it will not last as long as steel but I had some and it worked so I put it to the test. Seems to be working great.

Copper is OK, as long as it's well-supported. It has a habit of fatigue-cracking due to vibration, usually at fittings, unless it's bracketed to something solid every few inches.
Jerry

(check ebay)


Jerry

Zinc coated copper line is very easy to bend and flare. It will last longer than I.