Author Topic: Potential fuel starvation (Read 17255 times)

Jerry · « **Reply #20 on:** August 12, 2013, 06:26:40 PM »

Yep it's wired to my dead-man switch.
The fuel pump is an option. If you are using 6 gal tanks in back, I see no need for it (or if you're underpowered). If you are counting on a vacuum operated pump to pull the fuel 12-13' You may want to consider the price of the pump vs the price of a leaned out motor. Your call.
The proper wood and resin is not debatable.

Rosscoe · « **Reply #21 on:** August 12, 2013, 07:57:06 PM »

We didn't get out again tonight. Joni hasn't been feeling good and about the time she got home, some dark clouds rolled in, it got windy and the temp dropped what felt like 10 degrees.

While on the subject to safety with E fuel pumps, I was thinking about what would happen if my engine died like it has been and coasting to a stop, the key would still be on hence the pump would still be pumping. That doesn't sound good to me. Maybe its not a big deal?
I did buy a safety shut of switch that shuts the pump off if the oil pressure drops below 5 PSI I think, but doubt it will arrive by and be installed before thursday.

Jason · « **Reply #22 on:** August 12, 2013, 08:06:47 PM »

you worry too much ross! The needle and seat in the carb should be able to handle the low pressure. If you are really worried about it do what Rich did and wire it to the oil pressure sender. Get out on the water and see what happens!

Rosscoe · « **Reply #23 on:** August 12, 2013, 08:09:30 PM »

Yes sometimes I do. I just don't like fires unless I started them.

Oil pressure safety switch on order.

Rosscoe · « **Reply #24 on:** August 13, 2013, 06:54:12 PM »

So much for the potential fuel starvation being due to a dirty tank, or filter or fuel pump. Its either the carb or an electrical issue. That is all that is left.
Made it a couple of hundred yards from the landing tonight before it died. Wouldn't start right away so we dropped anchor to keep from floating further from the landing, let it cool down and I readjusted the idle mixture screws because restarting seems to have gotten worse since we messed with them last thursday.
Needless to say, we're pretty disgusted with this whole thing. Keep throwing money at it and get the same results. Like it has been said before, it does seem to be heat related and I thought maybe, just maybe, me bending a new line to the carb that didn't make an "s" turn behind the water pump and didn't have a small kink in it, would do the trick. If there was enough time and money, I'd just drop it off at a marine mechanic and be done with it.

Rosscoe · « **Reply #25 on:** August 13, 2013, 07:49:14 PM »

1971 Glastron V175 for sale...
Thousands spent. Make offer. J/K

75starflight · « **Reply #26 on:** August 13, 2013, 07:57:46 PM »

I really hate to have this thought Ross, but has the engine ever been apart? Sitting here thinking about this the 140 I got from joe would kind of do the same thing, and it had a cracked head. My thought is could it be hydro locking? Have you checked the oil lately to check for moisture in the oil.

I just had another thought, has the jet ever been gone through? You say it does it after the engine warms up, could a bearing be getting hot enough to start locking up to cause the engine to pull hard and then die. Then once everything cools down it works fine again.

One question, isnt the jet always pumping water even when not in gear? If it is, then if a bearing is locking up that would explain the hard starting issue. So once you do get enough torque built up in the drive line to break what is locked up loose the engine will fire up again.

Just some thoughts I came up with watching a tractor being dyno'd today. Because our PTO dyno will shut down a tractor if it gets pulled down too hard.

Rosscoe · « **Reply #27 on:** August 13, 2013, 08:33:10 PM »

Lots of good ideas.
The motor is a fresh rebuild with probably 10 total running hours. Previous motor had a cracked block and I know very well now what water and oil looks like.
The jet is of unknown condition. I was hoping to get a season or two out of it before rebuilding it but I think the jet rebuild "kitty" is gone.
When the motor is running, the impeller is turning. The hard starting issue isn't that it turns over hard. It spins like it should, just wont fire for awhile.
When it dies, its like turning the key off, except now with the electric fuel pump, I know its not actually losing 12V, at least not where I tied it in...on the ballast resistor. Pump kept running until I turned the key off.

75starflight · « **Reply #28 on:** August 13, 2013, 08:44:52 PM »

Sounds like the coil is over heating but you have an HEI, it will be interesting to see what it is doing in person this weekend. I had that happen with a car in high school. Took forever to pin point the actual problem.

Jason · « **Reply #29 on:** August 13, 2013, 08:51:44 PM »

Did you try what I said and bypass all wiring to the coil? It does seem more electrical than fuel the way it kills. Could be a short in the ignition switch or something going on somewhere in the wiring.

wiliermdb · « **Reply #30 on:** August 13, 2013, 09:10:46 PM »

Maybe I'm making waves in this "subject pond" but it seems that it is being over thought.

What did the engine come with from the factory? How long did it last? With all the quality makers such as Holley, Mallory and more I'm sure a new mechanical fuel pump will fix the issue if that is indeed what the source of the problem is.

Have you tried running the motor in the driveway and let it heat up? In a tank? If you feel it may be a heat/fuel issue, run on the lake without the engine cover and see what it does. Put a long hose on the fuel pump output that goes to the carb and run it into an empty gas can. Kill the ignition and turn the motor over and see how much fuel output you have. See what you have in the can. That will tell you if you have ample flow. You can rent a fuel pressure gauge and put it inline and see what you have while running. That will answer another question. It takes a lot of heat to vaporize fuel. Is your motor running hotter than normal?

All of our outboards and I/O's came with mechanical fuel pumps and they have worked fine for decades. Mine is original from 1977. Never broken into since 2005 from the original owner and I have done nothing to it in the three years I've had it. I ran the 115 this weekend for a total of 16 hours in temps reaching 102 degrees. Water temp was 80 degrees. That's hot.

Just for peace of mind I would change every inch of fuel line from the tank and under the hood. Not that expensive and you know it's new.

One thing I have heard from at least a dozen of marine mechanics of all calibers (one being a former mechanic for Reggie Fountain Racing) is that with the ethanol issue, many people are over-filtering their fuel and causing low fuel supply to the engine. The Fountain guy said he gets many OB's in with fuel/water filters, factory filter mounted in the engine and sometimes a third filter. Too many filters for the pump to try and pull through. Even with the humidity down here (85 - 100%) from May to October you will hardly find fuel/water filters on any boats that are running mechanical fuel pumps. Each filter is a restriction.

I know it's frustrating trying to figure out what gremlin is causing you so much stress. Make a list of the simple things that we tend to overlook in haste and start eliminating them one by one. You could have a bad coil that is overheating? That happened on my dad's '69 Merc with a 429. Drive it in Louisiana heat for about an hour and it would die. Checked everything and someone said to change the coil. Never did it again for the remaining 5 years he had it.

fireman24mn · « **Reply #31 on:** August 13, 2013, 10:33:11 PM »

My 18 had a kind of similar problem last year and I found the choke wire and a wire that went to the HEI melted together. It would run but then when shut off would not start. Have you checked wiring? I would look at the wiring cut the wrap on it if there is any and look for a melted wire. That was another problem I had with my trim this year. Couldn't find anything that caused it but cut out the bad and put in new and works fine.

thedeuceman · « **Reply #32 on:** August 14, 2013, 06:50:25 AM »

I will bring yer HEI and all Jasons stuff too, and the module i have. i will also bring my fuel pr gauge and of coarse i go no ware with out a bunch of tools.
make sure you drag yer extra fuel line stuff (hose fittings clamps) just in case
WE WILL GET IT GOING !!!!!!

Jason · « **Reply #33 on:** August 14, 2013, 07:11:10 AM »

Ross, bring my old elec fuel pump if you are done with it. I am working on converting my Tempo to carbureted.

I will bring my inline spark tester so we can make sure we are getting spark when it stalls out. And a different set of resistors.........just because we are running out of things to try!

Rosscoe · « **Reply #34 on:** August 14, 2013, 08:44:46 AM »

Quote from: 74GlasCarlSS on August 13, 2013, 08:51:44 PM

Did you try what I said and bypass all wiring to the coil? It does seem more electrical than fuel the way it kills. Could be a short in the ignition switch or something going on somewhere in the wiring.

No I haven't because I am a little concerned about bypassing the ballast resistor and blowing my module but actually the coil alone is supposed to have enough resistance according to the guys at Prestolite. Basically they said for running such as on a drag strip without the b res is ok but for reliability for on the "street' use, its better to use the resistor. I am looking for reliability.

thedeuceman · « **Reply #35 on:** August 14, 2013, 08:48:29 AM »

Ross, when are you planning to get there tomorrow ?

Rosscoe · « **Reply #36 on:** August 14, 2013, 08:59:59 AM »

Quote from: wiliermdb on August 13, 2013, 09:10:46 PM

Maybe I'm making waves in this "subject pond" but it seems that it is being over thought.

What did the engine come with from the factory? How long did it last? With all the quality makers such as Holley, Mallory and more I'm sure a new mechanical fuel pump will fix the issue if that is indeed what the source of the problem is.

Have you tried running the motor in the driveway and let it heat up? In a tank? If you feel it may be a heat/fuel issue, run on the lake without the engine cover and see what it does. Put a long hose on the fuel pump output that goes to the carb and run it into an empty gas can. Kill the ignition and turn the motor over and see how much fuel output you have. See what you have in the can. That will tell you if you have ample flow. You can rent a fuel pressure gauge and put it inline and see what you have while running. That will answer another question. It takes a lot of heat to vaporize fuel. Is your motor running hotter than normal?

All of our outboards and I/O's came with mechanical fuel pumps and they have worked fine for decades. Mine is original from 1977. Never broken into since 2005 from the original owner and I have done nothing to it in the three years I've had it. I ran the 115 this weekend for a total of 16 hours in temps reaching 102 degrees. Water temp was 80 degrees. That's hot.

Just for peace of mind I would change every inch of fuel line from the tank and under the hood. Not that expensive and you know it's new.

One thing I have heard from at least a dozen of marine mechanics of all calibers (one being a former mechanic for Reggie Fountain Racing) is that with the ethanol issue, many people are over-filtering their fuel and causing low fuel supply to the engine. The Fountain guy said he gets many OB's in with fuel/water filters, factory filter mounted in the engine and sometimes a third filter. Too many filters for the pump to try and pull through. Even with the humidity down here (85 - 100%) from May to October you will hardly find fuel/water filters on any boats that are running mechanical fuel pumps. Each filter is a restriction.

I know it's frustrating trying to figure out what gremlin is causing you so much stress. Make a list of the simple things that we tend to overlook in haste and start eliminating them one by one. You could have a bad coil that is overheating? That happened on my dad's '69 Merc with a 429. Drive it in Louisiana heat for about an hour and it would die. Checked everything and someone said to change the coil. Never did it again for the remaining 5 years he had it.

We did swap out the coil early on during this troubleshooting with no improvement. The "best" result were achieved with using a remote tank bypassing all filters and rusty gas tank (now fixed) and electric fuel pump but I'm thinking that was a fluke now. It does seem heat related. Last night it died not too long after reaching temp (160) Maybe thats too hot but even if it is, it is causing something else to fail.
Had a brand new Holley mechanical fuel pump that I just switched to a Holley electric unit this week.
All fuel line replace within the last week as well.

Rosscoe · « **Reply #37 on:** August 14, 2013, 09:06:45 AM »

Quote from: fireman24mn on August 13, 2013, 10:33:11 PM

My 18 had a kind of similar problem last year and I found the choke wire and a wire that went to the HEI melted together. It would run but then when shut off would not start. Have you checked wiring? I would look at the wiring cut the wrap on it if there is any and look for a melted wire. That was another problem I had with my trim this year. Couldn't find anything that caused it but cut out the bad and put in new and works fine.

All my wiring back there has been replaced but I suppose something could have melted. Of course I have it all cable tied and in plastic wire loom to clean it up and will likely have to pull that all apart.

Rosscoe · « **Reply #38 on:** August 14, 2013, 09:07:31 AM »

Quote from: 74GlasCarlSS on August 14, 2013, 07:11:10 AM

Ross, bring my old elec fuel pump if you are done with it. I am working on converting my Tempo to carbureted.

I will bring my inline spark tester so we can make sure we are getting spark when it stalls out. And a different set of resistors.........just because we are running out of things to try!

Yup, its packed as well as your plug wires.

75starflight · « **Reply #39 on:** August 14, 2013, 09:08:48 AM »

Ross is your key switch 3 or 4 position? I have the old one from Phoenix Rising we could bring with us that was working well when I switched it out this spring. If it comes down to that.