fuel pick up tube

[hammerhead]

checking out the fuel system before we put her in this year. pulled the anti siphon fitting off to check that but could not get the fitting off the tank to check the pick up tube. is there a screen in the tube or do i not worry about it?

[prowlersfish]

Good chance it has a screen on it . Blow back thru it

[hammerhead]

so dont try to remove?

[prowlersfish]

so dont try to remove?

You posted you could not remove it so I assumed it won't come out . But if you can great . I assume you are having fuel flow issues ?

[hammerhead]

we are thinking so. rebuilding the carbs now and just going thru all the fuellines since we bought this last year. could only get about half the rpms that Bob said we should be getting. Only had a socket to day but when i go back ill take a 6 point wrench and a breaker bar and see if i can get it to budge

[P-Dogg]

If Psfish has direct experience on your model of boat, ill defer, but as an engineer, id never install a filter in an inaccessible location.

There are no filters on the pickup tubes in my '85 tricabin. As part of the joys of parenting and family boating, my son helped me winterize two years ago. Short story is, 2.5 gallons of waterline anti freeze into the fuel fill.....

I bought myself a gas tapper and pumped water out of the fuel tank -- about 10 gallons worth, and became one with my fuel system from pickup tubes to quadrajet jets.

Back to your problem. There have been issues with debris clogging the anti siphon valve. Check that. And have you checked all of the filters (three total in my system, for propulsion engines), including the one where the fuel line attaches to the carb (if so equipped)? Not just checked them, but replaced them, more to the point.

You reported low RPM. Is that in the water, with clean props and hull? I had low RPM problems and it turned out that it was a distributor issue -- springs IIRC.

How is the fuel pressure? Fuel pump up to spec?

Last clue "since we bought this last year." Did it ever make RPM? Is it propped correctly?

[prowlersfish]

If Psfish has direct experience on your model of boat, ill defer, but as an engineer, id never install a filter in an inaccessible location.

That is funny . You need to spend a week in my shoes lol. Sadly in a lot of real world cases its where can we make it fit .more true in auto motive then boats but....... Ok now that I said that I agree with all else .

Now with that said Trojan did not put screens on the tank pick ups per a Trojan engineer . But I have run across it more the once . When you have a 30-50+ year old boat , things get changed . Fuel systems parts including tanks are high on the list . My F30 had screens , but it was not the tank it came with .


While Fuel issues can be the cause of low rpm so can ignition issues and long dirty running gear and bottoms . over propping and tired engines and of corse all the gear and toys we ad to our boats


Back to the fuel pick up . see if you can blow back through it .

Now what boat / engines do you have ? your max rpm and speed ?

[prowlersfish]

Let me add if you can blow back through the pick up no need to pull it out .

[WayWeGo]

The best automotive diagnostician I ever met always said "If you think it is the carburetor, check the ignition. Once you are convinced it is the carburetor, check the ignition more thoroughly." I have found over the years that he is pretty accurate on this!

[hammerhead]

If Psfish has direct experience on your model of boat, ill defer, but as an engineer, id never install a filter in an inaccessible location.

Now what boat / engines do you have ? your max rpm and speed ?

1977 f-30 with twin 318's port rpms 1800 star 2100. to speed 19 mph. all new filters and water separator. will check anti siphon next weekend when we get back out there.

[10meterman]

I would suggest checking your fuel pressure ,,, its simple and easy to do,, will answer the question of
fuel delivery. Carb. floats set at proper height? I would also make sure ignition timing is correct , both base and full advance.

[hammerhead]

Just a follow up. we rebuild the carbs and they were way out of adjustment.fuel pressure was at 6 lbs on the port and 4 on the starboard. electric pumps. the pick up tube in the port was 1/2 copper and the starboard was 3/8 rubber hose. also the pumps were installed right at the tank. what size should the pick up tube be? also since a lot on the boat has been changed what would the correct electric pumps for this boat?

[kallen]

Lets look back to your past posts in 2018 about the carb problems.Seems like you still have the same problem. Start with a basic tune up and compression test. You haven't said anything about what other work has been done. On my 1981 F32 the fuel pickups had No screens just 8" of copper tube and 22" of fuel hose. No Trojan ever came with electric fuel pumps.What happened to the mechanical pumps. When a fuel pump (mechanical) is tested note the pressure and volume. WayWeGo is right on.

[hammerhead]

Lets look back to your past posts in 2018 about the carb problems.Seems like you still have the same problem. Start with a basic tune up and compression test. You haven't said anything about what other work has been done. On my 1981 F32 the fuel pickups had No screens just 8" of copper tube and 22" of fuel hose. No Trojan ever came with electric fuel pumps.What happened to the mechanical pumps. When a fuel pump (mechanical) is tested note the pressure and volume. WayWeGo is right on.

thanks for the reply but you just repeated what i said. I said we just rebuilt the carbs but since its on blocks yet we cant test. i know they didnt originally come with electric pumps as i stated that many things have been changed by previous owners. we just purchased last year.

[kallen]

When you do launch there will be lots of items to check. How many hours are on each engine So other than rebuilding the carbs and replacing the fuel lines what else has been checked ? You also asked what is the correct electric fuel pumps for this boat. Iam sure others will chime in on using electric pumps.