Help With Fuel Tanks Problem

Downbucket

Well-Known Member
Supporting Captain
Sep 8, 2021
63
3
Maine
Hi:
I have a 1998 Shamrock 22 WA. Engine is the Pleasurecraft 351. There are two new (past five years) 40 gallon fuel tanks. Last week I was out for a couple of hours and on return, just at the fairway to the anchorage, the engine quit. First thought was that I ran out of gas. Got towed to gas dock. Port side tank only took about 2 gallons. Starboard side took 40 gallons. So I didn't run out of gas. Obviously, the fuel in the port side tank is not going anywhere and I do not know why. The two cutoff switches at the fuel filter/water separator are both open. About 4 weeks ago, engine would not start. Before determining that the fuel pump and fuel filter/water separator needed replacement, I removed the deck boards exposing the two fuel tanks. Checked fuel hoses and anti siphon valves for both tanks and no blockage.
Anyone have an idea what might be the problem? Also, am I correct that each tank empties at the same time? This would seem to make sense otherwise the boat would be unbalanced if each tank drained separately.
Thanks.
Thanks everyone. I appreciate the help.
 

Tekeela

Well-Known Member
Feb 8, 2010
131
2
NC
Factor tanks were 49 gallon.
I have same year same model boat with TBI 350 in it. I have a 3 way valve so u manually select tank. The valve controls the return line as well so you can only return fuel to the tank you are drawing from. my guess is you have either this
Boating Accessories New GROCO Fuel Valve 6 Port GRO FV65038



or this
Moeller Marine Fuel Tank Three-Way Valve (3/8", Brass)
I did not know this 3-way with returnf valve existed, you ticked an item off of my rebuild list. Thanks!
 

Gary S

Well-Known Member
Feb 4, 2010
1,667
165
Algonquin Illinois,Key Largo Florida
Unless you have a diesel engine fuel is not returned to the tanks. Gas engines do not return fuel. The 3 way valve is for selecting between tanks. It can be improperly plumbed so that it draws from 1 tank only and shuts off fuel when turned to other tank. Suggest checking 1st the draw tube on the tank and make sure it is clear. Fuel line with a primer bulb is an easy way to see if you can draw from the tank.
Good luck.
Dan Avoures
Naval Architect.
Dan it depends on what engine you have . Older Pleasurecraft engines say a MPI fuel injected Ford GT40's do in fact return fuel to the tank. I have a factory installed one in a Nautique and was this close to putting one in my 20 Shamrock. Here is a picture of my Nautiques fuel tank- the fuel line with the red tape is the feed line the other is the return-

100_1516.JPG

Here is the GT40 that was going into my 20. White arrow is low pressure fuel pump that transfers fuel from tank to high pressure pump located inside silver cannister called by Pleasurecraft the fuel control cell or commonly the FCC. Yellow arrow is the feed from high pressure pump to engines fuel rail. Green arrow is excess return from fuel rail to the FCC. Red arrow is return to the fuel tank excess from the FCC


GT40 fuel system.png
 

Classichondaman

New Member
Jun 28, 2019
1
0
I still do not understand how these two tanks work but it appears problem solved. I went out over the weekend and did not find what Shamrock1969 posted but I did find a shutoff at the fuel filter/water separator. The hose from each tank is connected to one side of the fuel filter/water separator. I shut the valve for the starboard side leaving the port side open. (The engine had been using fuel from the starboard side tank when both valves were open.). The engine started and ran fine. So, it appears that one side has to be shut off and then when you run out of fuel, you close the valve and open the other. Don't understand why you cannot leave both sides open and either the tanks drain simultaneously or when one side empties, the other side then sends the fuel. No matter, it works. Thanks for all of your suggestions. Now my wife and I have decided to sell the boat. While it runs great and we like it, we want something with a bigger cabin rather than the cuddy. I'll be posting it in the for sale forum soon. Thanks again.
Interesting. I have had my 22 for 4 years and it never occurred to me that you would be able to run both tanks simultaneously! I just keep an eye on the amount in each tank and switch back and forth as required. Btw, I think all trucks/vehicles with two tanks have a similar switch allowing fuel to flow from one or the other, but never both. I know what you mean about the small cuddy in these boats, we wish ours was bigger too. But we love the way the boat looks and runs otherwise. Good luck with the sale.
 

Mistress

Moderator
Staff member
Supporting Captain
Jan 22, 2005
7,475
237
San Jose, CA
Unless you have a diesel engine fuel is not returned to the tanks. Gas engines do not return fuel. The 3 way valve is for selecting between tanks. It can be improperly plumbed so that it draws from 1 tank only and shuts off fuel when turned to other tank. Suggest checking 1st the draw tube on the tank and make sure it is clear. Fuel line with a primer bulb is an easy way to see if you can draw from the tank.
Good luck.
Dan Avoures
Naval Architect.
Ummmm...no.
 
Nov 8, 2021
9
0
Down bucket said he had a 1998 351. I have a 2000 351 which has a 4 barrel carburetor not multiparty pinker injection, so does not have a fuel return. I assume that since he has 1998 engine it is carburetorated like my engine.
 

Downbucket

Well-Known Member
Supporting Captain
Sep 8, 2021
63
3
Maine
Down bucket said he had a 1998 351. I have a 2000 351 which has a 4 barrel carburetor not multiparty pinker injection, so does not have a fuel return. I assume that since he has 1998 engine it is carburetorated like my engine.
Yes, carburetor.
 

Daddy's Rich

Well-Known Member
Oct 7, 2005
65
0
Hi:
I have a 1998 Shamrock 22 WA. Engine is the Pleasurecraft 351. There are two new (past five years) 40 gallon fuel tanks. Last week I was out for a couple of hours and on return, just at the fairway to the anchorage, the engine quit. First thought was that I ran out of gas. Got towed to gas dock. Port side tank only took about 2 gallons. Starboard side took 40 gallons. So I didn't run out of gas. Obviously, the fuel in the port side tank is not going anywhere and I do not know why. The two cutoff switches at the fuel filter/water separator are both open. About 4 weeks ago, engine would not start. Before determining that the fuel pump and fuel filter/water separator needed replacement, I removed the deck boards exposing the two fuel tanks. Checked fuel hoses and anti siphon valves for both tanks and no blockage.
Anyone have an idea what might be the problem? Also, am I correct that each tank empties at the same time? This would seem to make sense otherwise the boat would be unbalanced if each tank drained separately.
Thanks.
My 26' diesel has a selector switch that you use to direct which tank you are drawing from... since its a diesel there is a second selector that directs which tank the returned fuel (fuel delivered by the lift pump to the injector pump but not metered through the injector pump to the injectors) goes to... are you sure you don't have a similar set-up that might have been installed when you re-fitted your tanks?
 

Jim Mcconn

Member
Jun 21, 2021
5
0
Hi:
I have a 1998 Shamrock 22 WA. Engine is the Pleasurecraft 351. There are two new (past five years) 40 gallon fuel tanks. Last week I was out for a couple of hours and on return, just at the fairway to the anchorage, the engine quit. First thought was that I ran out of gas. Got towed to gas dock. Port side tank only took about 2 gallons. Starboard side took 40 gallons. So I didn't run out of gas. Obviously, the fuel in the port side tank is not going anywhere and I do not know why. The two cutoff switches at the fuel filter/water separator are both open. About 4 weeks ago, engine would not start. Before determining that the fuel pump and fuel filter/water separator needed replacement, I removed the deck boards exposing the two fuel tanks. Checked fuel hoses and anti siphon valves for both tanks and no blockage.
Anyone have an idea what might be the problem? Also, am I correct that each tank empties at the same time? This would seem to make sense otherwise the boat would be unbalanced if each tank drained separately.
Thanks.
 


Latest posts

Top