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Master Earl Craft
07-07-2013, 11:21 AM
My Prostar 190 w/ 351 Indmar (HO) starts very hard after I run for a while. I really have to pump the throttle to get it to fire. It starts fine when cold and runs fine once it finally starts. I had the marina look at the electrical last winter and it was ok, so I am assuming there is a fuel / carburetor issue. I've adjusted the primary bowl to keep it from stalling when in gear at idle, but that is all I've done with the carb. I also replaced the fuel filters. I'm about to give in and send it to the marina, but would rather hang on to my life savings. Any suggestions?

93Prostar190
07-07-2013, 08:49 PM
Choke ok ?

cbryan70
07-07-2013, 09:28 PM
What model carb is on the boat?

Master Earl Craft
07-08-2013, 11:47 AM
Elect choke does not work okay. However, when the engine is warm, I have confirmed that the the choke is open.

Master Earl Craft
07-08-2013, 11:50 AM
The carb is a Holley with the Ford Part # F1JL-9510-EA R5048. I've read on this forum and others that the carb is junk for a marine application. I rebuilt it about 12 years ago. I'm not 100% convinced it is the carb, but had the marina confirm elect was okay over the winter. I should have left it there.

chriscraftmatt1976
07-08-2013, 11:55 AM
My 93 does the same, but if I peg the throttle in reverse, she fires right up, and runs good. Just gotta be ready to take the throttle down quick. For sure a carb issue, but I'm not dealing with it until fall since the boat runs good. I'd guess yours is the same. I've got a holley 4160, and I hate it. Been a real pain. I looked at a holley throttle body injection setup to replace it, but kinda pricey. Anybody have experience with that?

Master Earl Craft
07-08-2013, 12:02 PM
Yep. Exact same issue. I too peg the throttle in reverse as well to get a start, but hate to have "tricks" when starting in case others will drive the boat. I also occasionally have rough idle issues. Does yours idle rough as well from time to time? Would like to know if you get anywhere with the TBI conversion.

chriscraftmatt1976
07-08-2013, 12:23 PM
Man, I do, really rarely. It'll run fine for a week, then for a few seconds idle rough, then bounce back to normal. I think she's dumping just a liiiiiitle too much gas, but I haven't tried adjusting the floats yet. I'm sure that'd probably fix it. Like I said, 4160 has been a real bummer for me. If I get into the injection thing this winter I'll keep you updated. I may pull the trigger. If not, I'm probably going to replace with a different carb anyway. This one ***.

TRBenj
07-08-2013, 12:49 PM
My 93 does the same, but if I peg the throttle in reverse, she fires right up, and runs good.
Anyone who thinks they need to "pump the throttle" to get a carb'd engine to start when warm should try the trick described above. Same goes for anyone who thinks their carbureted boat suffers from "heat soak". If it works, then the engine is flooded and needs air, not gas- and every time you pump the throttle you add both! Just open the throttle once and it'll start a little easier until you have a chance to fix the problem.

In the above described scenario, pop the flame arrestor off the carb and take a look down the throat to see whats happening. Check it at idle (engine running) and directly after shut down. Chances are that you will see fuel dripping. Fuel should not be dripping from the boosters while at idle, and should not be dripping at all with the engine off. Dripping fuel is the result of either a)float set too high or b)needle and seat issues. Both will allow the bowl to fill past the point where it should, and the excess fuel will end up dripping in the main body of the carb, past the butterflies and puddle in the intake manifold. EI, flood the engine.

If the engine previously ran well with the carb set up as-is, chances are good that its a needle and seat issue. It could be that the 2 parts are worn out and dont seal anymore. It could be that there is a bit of debris lodged between the 2. In any case, the solution is to pull the bowl and replace the needle and seat with a properly functioning pair. If something is new about the carb- either a fresh rebuild or a new carb- then the high float setting becomes a stronger possibility. You are also not safe from the needle and seat issue, as the poor seal between the 2 parts could be from a poor mismatch of low quality parts. The issue is surprisingly common.

MI_Corey
07-08-2013, 12:56 PM
My dad has the same boat and had the same issue. After fighting it a couple years he gave up and bought a new carb. That was about five years ago and no problems since.

Master Earl Craft
07-08-2013, 02:22 PM
chirscraftmatt1976 - Your note about the new carb, "I'm probably going to replace with a different carb anyway. This one ***," didn't show the model number. Are you refering to the Holley 4150. I found a post from 2006 which had a couple reccomendatons... see below.

There are two options that will work on your application. The first is part #0-80559 (Holley 4150, 600CFM). This is a 600 CFM unit that should be plenty big for a 285 horsepower application, and will make your boat run like a FI boat.

The second option is part #0-9015-1 (4160 750 CFM). This is the 750 CFM unit, which is probably overkill, unless you have dreams of swapping cams/heads/etc, to create a high performance gas-guzzler.

You can find these carbs Vic Hubbard's marine shop for $449: https://vichubbard.com/shop/product.php?productid=61964

Master Earl Craft
07-08-2013, 03:27 PM
My dad has the same boat and had the same issue. After fighting it a couple years he gave up and bought a new carb. That was about five years ago and no problems since.
What new carb did he get?

Master Earl Craft
06-23-2014, 05:51 PM
I made the leap and replaced the 4010 with a 4160. Still have the issue with hard start when warm. I may have a little work to do yet setting the floats and idle mix, but cannot foresee that making enough of a difference to solve this. Does anyone believe that perhaps it is electrical? Should I replace plugs and wires? Is my coil getting too hot and not efficiently getting enough juice to the plugs? Do I need a new distributor?

If I knew what I could get for my boat, I'd sell is and look for a '94 with EFI.

Jerseydave
06-23-2014, 08:01 PM
[QUOTE=TRBenj;954807]Anyone who thinks they need to "pump the throttle" to get a carb'd engine to start when warm should try the trick described above. Same goes for anyone who thinks their carbureted boat suffers from "heat soak". If it works, then the engine is flooded and needs air, not gas- and every time you pump the throttle you add both! Just open the throttle once and it'll start a little easier until you have a chance to fix the problem.

In the above described scenario, pop the flame arrestor off the carb and take a look down the throat to see whats happening. Check it at idle (engine running) and directly after shut down. Chances are that you will see fuel dripping. Fuel should not be dripping from the boosters while at idle, and should not be dripping at all with the engine off. Dripping fuel is the result of either a)float set too high or b)needle and seat issues. Both will allow the bowl to fill past the point where it should, and the excess fuel will end up dripping in the main body of the carb, past the butterflies and puddle in the intake manifold. EI, flood the engine.

^Check the carb for dripping again while it's hot and idling, and also when you shut it off. There should be no gas dripping from the boosters.

If that looks good, start with basics on the electrical system. New points and condenser, set the dwell (with a dwell meter) and the timing. A coil can go bad and get hotter than normal causing a problem with hot starting, so don't discount that either. I think a new coil is pretty cheap, might be worth getting one. Check your ballast resistor too if you have one. Also a cheap part to replace.

madcityskier
06-23-2014, 11:28 PM
Chriscraftmatt1976 stopped hanging out here. I believe he ended up replacing the fuel lines and the overflow valve. That seems to have made a big difference. His sat for a couple ears with 10% ethanol in it, and the fuel lines were very gummy. Ran great 2 weeks back when he took me out.

thatsmrmastercraft
06-24-2014, 12:03 AM
I made the leap and replaced the 4010 with a 4160. Still have the issue with hard start when warm. I may have a little work to do yet setting the floats and idle mix, but cannot foresee that making enough of a difference to solve this. Does anyone believe that perhaps it is electrical? Should I replace plugs and wires? Is my coil getting too hot and not efficiently getting enough juice to the plugs? Do I need a new distributor?

If I knew what I could get for my boat, I'd sell is and look for a '94 with EFI.

You could have some resistance in the electrical system preventing battery voltage from being present at the coil (less the ballast resistor). Check your voltage at the + side of the coil with the key on. Also check voltage at the connection at the ballast resistor. Also check cranking voltage at the coil. Something as simple as a battery cable with high resistance can cause this. I just replaced my battery cables for this reason.

Master Earl Craft
06-24-2014, 08:33 AM
No points, condenser, or ballast resistor. Replaced with Electronic Ignition. The marina also replaced the coil before I started with the carburetor.