Runs out of fuel in barrel with tank on ground

[Bearcamp]

1992 Force 15 hp. It all started off with the carb needed rebuilt from sitting, so I did that. Got it running , worked fine as long as I held the tank about waist high. So next I replaced the fuel pump dia and gaskets. Put it in a barrel fired right up, idled in neutral, put it in gear and throttled up great. BUT as long as I have the tank on the ground it runs out of feul. If I hold the tank waist high it'll run forever. So in all I replaced pump dia, gaskets, fuel hose, primer bulb, rebuilt carb, plugs and new tank with hose. Is this normal? My Johnson 20 hp don't do it? There is about 3 feet from top of the barrel to the ground.

 

[12Footer]

Re: Runs out of fuel in barrel with tank on ground

No that isn't normal. It has to be an air leak in the supply somehwere, the tank not venting (loosen cap and try it to elliminate that possablilty), or insufficiant compression. The fuel pump runs on engine compression,as does the carb on vacuum, which is the other end of compression.<br />I've seen motors so fouled with carbon, that they could not exaust properly, causing the same symptom. So if your compression tests ok, look for blocked exaust ports.<br /><br />But it's not the carb or reeds,or it wouldn't matter where the tank was.

 

[Bearcamp]

Re: Runs out of fuel in barrel with tank on ground

Replaced the fuel fitting cause the rubber o-ring was torn. Thought it was sucking air. Gas cap was vented.

 

[Scaaty]

Re: Runs out of fuel in barrel with tank on ground

Try replacing ANY hose or SEAL that is in some way releted to your fuel pump from the motor

 

[Bearcamp]

Re: Runs out of fuel in barrel with tank on ground

Did replace all fuel lines, pump dia and gaskets. Also replaced all gaskets in the carb. Where do I check for the exhaust carboned up?

 

[12Footer]

Re: Runs out of fuel in barrel with tank on ground

On the port side of this motor, there is a plate held on with 8 (or so) bolts. This consists of two metal plates with gaskets sandwiched-between them. This is the exaust cover and exaust plate (under the cover and gasket). It covers (and is part of) most of the the exaust circuit on your motor. Before removing it, purchase a new gasket set. This set may be hard to find, but you can also make them from standard gasket material from any auto parts supply house.<br />You'll also need something to remove the tar-like goop from everything. Sometimes it's more like coal than tar, but it's the same stuff.<br />Unfortunately, the only way to check is to remove the exaust plates and actually see.<br />Plugs can be an indication, but odds are the plugs have been changed.

 

[Bearcamp]

Re: Runs out of fuel in barrel with tank on ground

The plugs did look wet or oil fouled. This motor only has about 30-40 hours on it. But....it could've been idled around. I'll pull it off this week.<br />Thanks people.

 

[Bearcamp]

Re: Runs out of fuel in barrel with tank on ground

Ok, I removed the exhaust plate and it was very clean with no carbon build up. I talked to my friend who owns it today. He said that the motor only has about 8 hours on it. So....I did a compression check and it came out to 85 lbs per cylinder. I guess I'm back to checkin the fuel lines (which I already did) again. Any other ideas? Ya know, like I said, the same hose and tank worked great on my Johnson.

 

[eurolarva]

Re: Runs out of fuel in barrel with tank on ground

85 compression seems pretty low. Are you sure you got the exhaust gaskets sealed back up? I am not sure on a 15 HP but the fuel pump on larger motors uses compression to pump fuel. I would think with no carbon build up you should be pushing at least 120 compression.

 

[Bearcamp]

Re: Runs out of fuel in barrel with tank on ground

I'm going to take it apart again and check the gaskets just to make sure. Can one use any type of sealer on those gaskets? I imagine they get pretty hot. And yes the fuel pump dia works off compression. Has me stumped..............

 

[eurolarva]

Re: Runs out of fuel in barrel with tank on ground

I have the exhaust gaskets off of mine. I plan on using permatex aviation form a gasket to put them back together again. Here is the rating<br />Slow drying, non-hardening brush-top sealant approved for use in aviation as well as automotive applications. Temperature range -65°F to 400°F; resists gasoline, oil and grease. I got this stuff from NAPA.

 

[Bearcamp]

Re: Runs out of fuel in barrel with tank on ground

OK, I had 85 in the top cylinder and 100 in the bottom. Sorta thinking this could be part of the problem. I removed the exhaust plate and gaskets, coated them with a copper spray sealant and reinstalled. Also found out the head bolts were just a little loose. While I had the exhaust plate off I sprayed the pistons (best I could) with Deep Creep. Just in case they might of had some carbon on the rings. Right now it setting for a few hours to let the sealer set up. Then I do another compression test to see if it comes up at all. I sure hope so. Like I said, this motor only has about 8 hours on it. If compression don't improve........THEN WHAT? Any more ideas? I even removed the fuel pump dia and checked the holes to make sure they were open, they're ok.

 

[Bearcamp]

Re: Runs out of fuel in barrel with tank on ground

I just did a compression test again and I have 100 lbs. in top and bottom cylinder. Her it must have been one of 2 things. Either the head bolts were a little loose or sealing the exhaust gasket. Gonna start it up this week end and let you all know how I make out.

 

[12Footer]

Re: Runs out of fuel in barrel with tank on ground

Blown head gasket from a loose head bolt? You may have found it.<br />A '92 motor with only 8 hours tho might mean something. a stuck reed, or Check the exaust ports for insect nests. We have a a wasp down here in Florida that builds it's nest out of mud. We call them "mud dawbers". They like to build these nests in water intakes and carb bodies ...they seam to like the smell of gas, and since they build thier baby houses out of mud, they populate boatyards close to the water.<br />If you have any critters like that up there, it could happen. I've had them build nests in my water intake tube, and it drove me nuts.<br />The time thay built one in a fuel line, I found it right away.