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View Full Version : Watch out!!! AN Fuel Fittings



Forrest
05-17-2001, 04:51 PM
Folks, as many of you may know, lately I've been busy building and installing a new pair of 383's for my Magnum. All you guys well know, you just can't take the old engines out and stick the new ones in and be done. While the engines are out, it's time to add a set of K-planes, rework electrical this and that, re-route plumbing, new alternator mountings, Stainless Marine exhaust (fixed that problem, BTW), move stuff on the dash to make room for the tab switches, etc.

Well, yesterday I fired off the new port side 383 and man did it sound great! Got to do it right and break that flat-tappet cam in buy going from start immediately to 2000-2500 RPM and keep varying the speed in that RPM range for at least 20 minutes. That's all well and good, but when you are by yourself, about all you can do is sit on the side of the boat and keep a hand on the carb's throttle lever and watch the tach, temp, and oil pressure, and listen to how great it sounds. Oh, and it sounded great!!! Anyway, in preparation for an initial startup, I always keep at least three large fire extinguishers near by - just in case. After about ten minutes in to the run, I decided to take my eyes off of the gauges and start leaning over the engine to look around. Much to my chagrin, and in total horror, I saw a stream of 93 octane spraying out of the AN fitting that attaches to the output port of the mechanical fuel pump. Immediately, I lunged to kill the ignition and then grabbed the closest fire extinguisher. No fire. . . Thank you! Gasoline had sprayed all over the front of the engine, on the crank pulley, belt and over to the alternator, and was running down into the nice clean bilge. There must have have been a quart or more fuel in the bilge. After I figured that thre was no immeditate danger, I then removed the braided stainless-steel fuel line the goes from the fuel pump to the carb and took a good look at fitting in question. Right off, I didn't see a problem. The fitting on the fuel pump looked good, too. With that, I decided to take a very close look at the flared part of the Russell Endura aluminum AN fitting and what I found was a very hard to see hair-line crack across the flaired mating surface. Apparently when the fitting is tighten down, the crack opens up. The Russell Endura fitting suppose to be one of the best aluminum AN fittings on the market, but still it's not USCG approved and I now see why. This fitting was not old - in use for less than a year - and on-and-off maybe three times. Also, I'm positive that I never over torqued the fitting and otherwise it still looks like new. Aluminum AN fittings and braided hose looks great but I'm now convinced that this stuff is dangerous in a boat. Stainless Steel AN fitting may be the answer, but if you look in the Areoquip catalog, the only USCG approved stuff is brass/bronze, and the fuel lines are still stainless-steel wire braided, but have a blue-rubber cover. Not all that pretty, but a hell of a lot better looking than burned boat and a tombstone.

Anyway, the engines are ready even though they still have aluminum AN fuel hoses and fittings. But those fittings will be gone soon.

Test run in the Gulf this weekend.


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Forrest

[This message has been edited by Forrest (edited 05-18-2001).]

Scott Pearson
05-17-2001, 07:12 PM
Forrest,
Sorry to hear about the problem you ran into. I ran all SS line and fitting on my boat. 1/2 feed and 3/8 return if I run fuel injection in the future. I had a hell of a time running all the line and flairing it was a bitch. I did run rubber line from tank to hard line and from fuel filter to hard line. I also pressure tested everything with about 5-7lbs of air. I ran into one leak that just needed to be filed a little.

I would do the same thing all over again. The rubber line all the way up to motor from tank is just scarry to me. I would not run Alum. Its just to soft.

(NJ)Scott

BigGrizzly
05-17-2001, 09:15 PM
Same thing happened with the Earls fitting, went to the airquip type for two reasions, 1 they are swedged and not the cutter type, 2)the flare is thicker, they take mote torque if you have brain faid. In the race bike abd cat the fuel lines are just a littel tighter than hand tight, think I put too much pressure on them.

Randy

Jamesbon
05-17-2001, 09:23 PM
Thank God! Glad you and your rig are okay!!

Where's a good joint to get USCG approved fuel line and fittings?

Forrest
05-18-2001, 10:24 AM
Nate, check the phone book under Industrial Equipment and Supplies. I'm sure that someone down there in Tampa or St. Pete carries the Aeroquip line.

Scott, 1/2" stainless tubing! No problem with fuel flow to that motor!

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Forrest

Scott Pearson
05-18-2001, 11:25 AM
Guys,
Call...GODMAN Hi-Performance Specialties. These guys are the best. There know the S**T. Ask for Ray Godman. They deal with all Fuel line stuff and have everything and I mean EVERYTHING! 1-800-456-2369