Reviving 1956 Evinrude Fleetwin 7.5 - Pressure Tank Issue

[Hofzer]

Re: Reviving 1956 Evinrude Fleetwin 7.5 - Pressure Tank Issue

Alright, according to this thread

http://forums.iboats.com/showthread.php?t=244807

80 is a good place to be, 60 is low, but fuctional.

I'm definatly in the low 70's, so I may be ok after all???

 

[BigB9000]

Re: Reviving 1956 Evinrude Fleetwin 7.5 - Pressure Tank Issue

its fineeeeee

 

[samo_ott]

Re: Reviving 1956 Evinrude Fleetwin 7.5 - Pressure Tank Issue

Yes, it should run fine in the mid 70's but will be a tad weak but I wouldn't worry about it. When you do a compression test, both plugs should be out and both plug wires grounded.

 

[BigB9000]

Re: Reviving 1956 Evinrude Fleetwin 7.5 - Pressure Tank Issue

$3 says if you remove the pull start system, and use the rope around the flywheel trick you'll get a higher PSI.

I did this for my 4hp putting out 30psi, with the rope flywheel, 100!
Im gonna go with the 100 reading.

 

[samo_ott]

Re: Reviving 1956 Evinrude Fleetwin 7.5 - Pressure Tank Issue

Haven't heard that one before. Is it due to the larger diameter and higher spin speed I guess?

 

[Hofzer]

Re: Reviving 1956 Evinrude Fleetwin 7.5 - Pressure Tank Issue

Great. Thanks. That's just what I wanted to hear.

I don't know where I got those original numbers from. I had been looking for compression test threads, and must have picked up something irrelevant.

My $50 pressure tank guy checked the tank. It builds pressure and comes complete with a hose and fitting. I'm going pick that up tomorrow. Score! I suppose I'll rebuild my current gasoline bomb, I mean tank, sometime soon.

It's time to order a carb kit, and an impellar kit. I'm still trying to find a new float on this site. If I open this carb up and find cork or something....

If all goes well, I'll have the carb rebuilt by the end of the weekend. I should have a chance to clean and gap the points before then.

If I'm going to be the guy on the lake with the '56 evinrude, it should run covetously well, right? Otherwise it is just some old clunker.

I hope to post some progress soon!

 

[BigB9000]

Re: Reviving 1956 Evinrude Fleetwin 7.5 - Pressure Tank Issue

Haven't heard that one before. Is it due to the larger diameter and higher spin speed I guess?

Im guessing speed.

I don't know if it actually matters, but it makes me feel better about my engine so I'm happy.

 

[Hofzer]

Re: Reviving 1956 Evinrude Fleetwin 7.5 - Pressure Tank Issue

removed

 

[BigB9000]

Re: Reviving 1956 Evinrude Fleetwin 7.5 - Pressure Tank Issue

My $50 pressure tank guy checked the tank. It builds pressure and comes complete with a hose and fitting. I'm going pick that up tomorrow.

Pushing the button doesn't build pressure, it sends gas to the carb.

Don't always believe what a seller says. give it the once over yourself first.

Also, if Evinrude make the kit still, it'll come with the float.

Evinrude kits > Seirra kits.

 

[Hofzer]

Re: Reviving 1956 Evinrude Fleetwin 7.5 - Pressure Tank Issue

Pushing the button doesn't build pressure, it sends gas to the carb.

Don't always believe what a seller says. give it the once over yourself first.

According to the seller, he pumped the pushrod, then was able to release pressure by removing the cap?

Are you saying that's BS? I suppose it could be error if he brought it out into the sun, etc.

BTW, I had been wondering why I couldn't just use my old tank with two hoses and a bulb, which your post reminded me of. In the end, I decided that the weak point would probably be the rubber bulb at 7 psi.

 

[Fuzzytbay]

Re: Reviving 1956 Evinrude Fleetwin 7.5 - Pressure Tank Issue

Pressure tanks knobs pump air into the tank, they do not pump fuel to the carb directly, its the air pressure that cause's the fuel to flow. Once runing the second line mark "air" which is hooked up to the engine and pumps back air pressure to keep the tank at pressure while running.

 

[BigB9000]

Re: Reviving 1956 Evinrude Fleetwin 7.5 - Pressure Tank Issue

ah. corrected I am

 

[Chinewalker]

Re: Reviving 1956 Evinrude Fleetwin 7.5 - Pressure Tank Issue

Actually the primer button DOES pump fuel directly into the carburetor. The primer button operates a diaphram driven fuel pump, not an air pump. You can prime the carb with the cap off the tank... The tank does not build up pressure until the motor starts running - or if it sits in the sun with the cap closed.

 

[Hofzer]

Re: Reviving 1956 Evinrude Fleetwin 7.5 - Pressure Tank Issue

Actually the primer button DOES pump fuel directly into the carburetor. The primer button operates a diaphram driven fuel pump, not an air pump. You can prime the carb with the cap off the tank... The tank does not build up pressure until the motor starts running - or if it sits in the sun with the cap closed.

It is definately a diaphram pump from the diagrams I have seen, but those can pump air too.

If it only pumped fuel to the carb, wouldn't the engine die out pretty quickly as the carb bowl emptied while the engine attempted to pressurize, say, a half empty six gallon can?

I guess the long and short for my purposes is to figure out if the pump works. I guess the only sure way to do so is a couple of tests. If I can reproduce the build up of pressure, then, well there's that.

I could also simply drepress the "valve" at the end of the hose fitting, and see if it puts out gas when the "primer" is pumped. That would answer the question of whether the mechanism works, regardless of how it works.

 

[Chinewalker]

Re: Reviving 1956 Evinrude Fleetwin 7.5 - Pressure Tank Issue

You'd be surprised - your motor will run for close to a minute, maybe longer at low idle, on just what is in the carburetor. Plenty long enough to get the tank pressurized...

 

[Fuzzytbay]

Re: Reviving 1956 Evinrude Fleetwin 7.5 - Pressure Tank Issue

Actually the primer button DOES pump fuel directly into the carburetor. The primer button operates a diaphram driven fuel pump, not an air pump. You can prime the carb with the cap off the tank... The tank does not build up pressure until the motor starts running - or if it sits in the sun with the cap closed.

I stand corrected too.

Chinewalker, I've never had to rebuilt one of these tanks yet, and currently I only have one, which is not any where close to needing a rebuild. Longer lines perhaps,but that is all. So is the pump inline then with the tank pickup tube?

 

[Hofzer]

Re: Reviving 1956 Evinrude Fleetwin 7.5 - Pressure Tank Issue

Chinewalker, I've never had to rebuilt one of these tanks yet, and currently I only have one, which is not any where close to needing a rebuild. Longer lines perhaps,but that is all. So is the pump inline then with the tank pickup tube?

I'm glad I'm not the only one learning from this thread.

Here is a diagram of the pump (pushrod).

I went to a good local evinrude deal and picked up a new gasket for the tank, among other things.

I'll post photos once I get to opening it up.

 

[samo_ott]

Re: Reviving 1956 Evinrude Fleetwin 7.5 - Pressure Tank Issue

It is definately a diaphram pump from the diagrams I have seen, but those can pump air too.

If it only pumped fuel to the carb, wouldn't the engine die out pretty quickly as the carb bowl emptied while the engine attempted to pressurize, say, a half empty six gallon can?

I guess the long and short for my purposes is to figure out if the pump works. I guess the only sure way to do so is a couple of tests. If I can reproduce the build up of pressure, then, well there's that.

I could also simply drepress the "valve" at the end of the hose fitting, and see if it puts out gas when the "primer" is pumped. That would answer the question of whether the mechanism works, regardless of how it works.

And how long would it take you to pump up the air pressure in a near empty 6 gallon tank using 1/2" button strokes to get enough pressure to move the fuel to the engine? Probably 20 minutes or so! It is a fuel pump. Three pumps or less and the carb bowl is full.

 

[Hofzer]

Re: Reviving 1956 Evinrude Fleetwin 7.5 - Pressure Tank Issue

And how long would it take you to pump up the air pressure in a near empty 6 gallon tank using 1/2" button strokes to get enough pressure to move the fuel to the engine? Probably 20 minutes or so! It is a fuel pump. Three pumps or less and the carb bowl is full.

Good point.

I just pulled the carb off and seperated it from the air quieter. was nice and dirty and full of sediment. I expect to find more of the same.

 

[Hofzer]

Re: Reviving 1956 Evinrude Fleetwin 7.5 - Pressure Tank Issue

I have a couple more questions.

I pulled the carb apart last night, sprayed it out and have it soaking for the night.

Should I replace the ceramic fuel filter, or just use the acetone and bake method I've seen elsewhere?

Also, is there any trick to threading the hi/lo needles back in. I see the old ones were basically threaded through the needle packing. As far as I can tell, I just need to take my time and make sure everything is square when I start threading them through.

Oh, and I found a wonderful place to buy parts, its a place called Vans in Grand Rapids, MI: www.vanssports.com . They had rebuild kits and other miscellanious parts from the parts diagram IN STOCK.

As you walk in, you are greeted by a 30's/40's johnson (onboard tank). They had outboard for sale ranging from a 50's Johnson Seahorse (3/3.5, I forget) through 60's evinrude fisherman's, to brand new motors.

Talking to the guy I bought a pressure tank from, Van's has been around for ever, and still has remaining stock of parts that can't be found elsewhere. All in all, it seemed like a good resource. They do nothing but outboards and some other two cycle engines. Their website isn't much or helpful, but they had everything I needed, including a new pressure tank gasket, in stock.