Question regarding outboard gas tank

[btaylor507]

Hi , I have a 1957 Evinrude Fastwin and it uses the older style pressure tank, which is in awful condition. I removed the top unit with the fill cap and custom build a new tank 23wx23dx7h est. 15 gallons -Pressure tested to 4 psi. I installed the old unit on the new tank. I haven't tried the tank yet but I'm wondering if there might be a way to upgrade to the single hose gas tank. Is there any other way around using the old pressure tanks and will this new tank even work?

 

[Scaaty]

Re: Question regarding outboard gas tank

Check the FAQ forum. Conversion is explained well, and in depth.
The old tank...for parts to rebuild, are available .."Laingsoutbords"
Good old motor...'fact, one on the best...

 

[F_R]

Re: Question regarding outboard gas tank

Hi , I have a 1957 Evinrude Fastwin and it uses the older style pressure tank, which is in awful condition. I removed the top unit with the fill cap and custom build a new tank 23wx23dx7h est. 15 gallons -Pressure tested to 4 psi. I installed the old unit on the new tank. I haven't tried the tank yet but I'm wondering if there might be a way to upgrade to the single hose gas tank. Is there any other way around using the old pressure tanks and will this new tank even work?

Congratulations on your new tank project. Now don't use it. Unless you convert your motor to a fuel pump. The top and bottom of your tank at 23 x 23 equals 529 square inches on the top and 529 square inches on the bottom. The normal operating pressure is 4-5 psi. I forget the relief valve blow-off pressure but it is somewhat higher than that. For the sake of arguement lets just say 10 psi. That means you have a potential of 10 psi times 529 square inches, or 5290 pounds of force trying to blow the top off. And also 5290 pounds of force trying to blow the bottom off. That's over a ton and a half of force on each. Even at normal operating pressure it is 5 x 529, or 2645 pounds...over a ton.

 

[btaylor507]

Re: Question regarding outboard gas tank

Hey thanks for the quick response guys! I'm new to the boating world so any help I get is greatly appreciated. I'm having trouble finding the rebuild kit for the pressure tank. I also found some information about converting from a double fuel line input to a single input but nothing for the certain type of motor I have. This motor looks to be in great condition and I'm very excited about getting it in the water. Any information you guys can find about a '57 18hp Evinrude FastWin would help me alot. Thanks again!

 

[tmcalavy]

Re: Question regarding outboard gas tank

The thread on converting to a modern one-line fuel pump works for several model motors from the 50s, including yours. Read it carefully and you can do this for less than $75.

 

[btaylor507]

Re: Question regarding outboard gas tank

I took the old pressure tank and cleaned it out really good. I added the mixed fuel and fuel cleaner, hooked it up, and it started right up on the 4th pull. I was amazed. The problem now is that its not pumping water. I'll have to try to find some information on changing a water impeller. Please let me know of any pointers. Thanks

 

[wbeaton]

Re: Question regarding outboard gas tank

You have to remove the powerhead to disconnect the shift linkage. Replace the cork gasket and o-ring on top of the driveshaft.

 

[btaylor507]

Re: Question regarding outboard gas tank

I went today and picked up a water impellar. I disconected the shift linkage..and removed lower unit with no problem at all. I removed the O ring on top of the drive shaft but I didn't see a cork gasket. Also I noticed on the water pump there is no gasket. Is there supposed to be one? I put it all back together with no problems and its seems to be pumping fine but I don't know how much water is supposed to be coming out. After running for a few minutes I can still hold my hand under the water coming out and the block stays cool but it just seems like more water should be coming out. Any info would be greatly appreciated. Thanks again!

 

[wbeaton]

Re: Question regarding outboard gas tank

Replace both the cork seal and o-ring while its apart. Without them water will get into the crankcase. The cork seal is #1 in the attached diagram.

Cork seal BRP 303355 or Sierra 18-2892
0-ring BRP 303347 or Sierra 18-7180

 

[btaylor507]

Re: Question regarding outboard gas tank

wbeaton Thank you so much for the info. When I pulled the lower unit I didn't see anything from the diagram on the shaft except a rubber O ring about a inch down. Could this cork gasket still be in the motor. Also where can I buy these parts? Thanks

 

[CATransplant]

Re: Question regarding outboard gas tank

At this point, you should post your question in the Johnson/Evinrude repair section of the forum. A lot of the folks who can answer your question spend most of their time there. Mention the engine model and problem in the title of the new thread and one of the many folks familiar with your engine will hop onto the question.

 

[wbeaton]

Re: Question regarding outboard gas tank

WHOA!!!

I'm so sorry, btaylor507. I thought you said your motor was a Fleetwin not a Fastwin. So sorry! I hope you didn't remove the powerhead. You will only find a single o-ring on the Fastwin. Replace it just the same.

 

[btaylor507]

Re: Question regarding outboard gas tank

Should I have any gaskets in the water pump itself? When I replaced the impeller I noticed there were no gaskets except for a rubber seal were the copper pipe inserts into the pump.

 

[wbeaton]

Re: Question regarding outboard gas tank

No gaskets required. Some use a little sealant under the housing, but I don't.

 

[btaylor507]

Re: Question regarding outboard gas tank

wBeaton Thank you for the info. I just put new gas lines on today so it looks like she ready to swim