Fuel starvation-stumped-135hp

[thehermit]

Mariner 1993 135<br />OK I am running out of ideas as fast as the motor runs out of fuel. Here is the scene:<br />New to me 135 runns fine off jerry jug but wont suck gas out of main tank. The tank is clog free/vented/and has gas in it. You can prime the motor from it and start the motor but the fuel pump will not keep it going off the main tank. However the feul pump does keep it going off a jug when it only has to pull gas from 4'. The fuel line is approximately 14' to a FW separater then 2' to motor. I have had the fuel pump apart and it seems fine (good even).<br /> <br />Question: Is there a max distance one of these fule pumps can draw from?????

 

[dingbat]

Re: Fuel starvation-stumped-135hp

The first thing I'd do is to rebuild the fuel pump. I can tell from experience that a diaphragm can look good yet not perform properly. <br /><br />The next thing I'd do is put the separator between the jerry can and see what happens. <br /><br />For what it’s worth, from my fuel tank to my separator is about 3’ and from the separator to the motor another 6’ or so. No problems

 

[thehermit]

Re: Fuel starvation-stumped-135hp

Can do. I can bypass the separator (brand new Tempo) to see if it will pull from the main tank. Also I can go from jerry through spearator to motor to test.

 

[thehermit]

Re: Fuel starvation-stumped-135hp

OK it is not the FW separator. Using a total of 6' of 3/8 line to fuel soarce it works (w or w/o separtor). Still will not suck fuel through 14-16' total of 3/8 line. <br />Weak fuel pump???<br />A buddy told me to up the feul line diamiter from tank to separtor to 1/2 or 5/8. Remember I can fill the line from the main tank with the primer bulb just fine. This rules out fuel pickup issue (I hope).

 

[Laddies]

Re: Fuel starvation-stumped-135hp

It sounds like your antisyphon valve is sticking

 

[thehermit]

Re: Fuel starvation-stumped-135hp

antisyphon valve?

 

[Clams Canino]

Re: Fuel starvation-stumped-135hp

In the main tank.<br /><br />-W

 

[rodbolt]

Re: Fuel starvation-stumped-135hp

its supposed to be the nipple part of the fuel draw tube. also be aware that some draw tubes have a filter screen in them. a quick session with a 20 dollar vacum gauge, t-fittings and hose will quickly determine the source.

 

[thehermit]

Re: Fuel starvation-stumped-135hp

hey guys, the main tank is a brand spanking new 28 gal tempo below deck. The 12 gals that are in it are its first fuel ever. The brass fitting that you attch the feul line to @ the tank, is that the pickup tube that is somehow removable?

 

[Perfidiajoe]

Re: Fuel starvation-stumped-135hp

Eliminate all the possibilities, disconnect the fuel line at the tank, & connect it to the portable, if it runs fine, the trouble is in the tank, look to anti-siphin,or A tube screan or other clog in the pick-up tube,(ball of silicone sealer or such), maybe some gasket goop from pick-up or float gauge.If it don't run fine look at connections to filters or water seperator, use your portable as a tool connect it up & down the line until the problem arises or goes away. Good Luck, Joe

 

[gss036]

Re: Fuel starvation-stumped-135hp

Is you new 28 gal tempo tank vented properly? Sounds like you need to check the tank over for correct installation. Maybe some real simple like the primer bulb on backwards.

 

[thehermit]

Re: Fuel starvation-stumped-135hp

Tank vented thru hull (all clear) pick up tube on tank clear (can blow back) going to new fuel pump will report back. I can prime and start motor from new tank but motor wont stay going off main tank by itself.

 

[Laddies]

Re: Fuel starvation-stumped-135hp

You might remove both end of the fuel line an vacume test the line for leaks and to see if it collapes, could be the inner part of the hose is collaped and you can't see it, is the fuel pickup tube OK--Bob

 

[thehermit]

Re: Fuel starvation-stumped-135hp

Hey Bob- just installed new fuel pump and filter and the problem still persists. Prime the motor with bulb and it will run fine then runs out of gas. Go back to bulb and it is empty and has lost its prime. How do you get the pick up tube out of a tempo below deck (black plastic) tank? It looks like it is not really set up to be removed-this is new tank Fuel line is also brand new tempo 3/8 gray line @ 14-16' to separator and another 3' to motor. I am leaning twards the pick-up tube but it does not seem "serviceable".

 

[Laddies]

Re: Fuel starvation-stumped-135hp

Maybe it won't come out of a plastic tank, may be you could hook a vacume gauge with a T into the system, first at the engine to find out how much and then at the tank to see what you have, you might also hooh the whole line that goes to the tank to a 6 gal tank to see if it's a tank problem

 

[thehermit]

Re: Fuel starvation-stumped-135hp

Laddie,<br />Hokked up the 16' line to a tank and it runs fine! That leaves (by process of elimination) the fuel pick up tube in the new tempo 28 gal tank. I dont know if they come out. I am going to try to call tempo. My fall back is to put in some sort of new pickup tube. Maybee there is some sort of antisiphon in the tank I dont know....at a loss here...at least I know where the problem is.

 

[Perfidiajoe]

Re: Fuel starvation-stumped-135hp

That's what I told you in the first place, use your portable as a tool to find the trouble spot. If the tank is new can you take the whole tank back? Good luck, Joe

 

[thehermit]

Re: Fuel starvation-stumped-135hp

as a follow up.....Tempo tank came with defective pick-up tube from the factory! After I got over the depression of the below deck nightmare. I replaced it (easier said then done of coarse). TH