Indmar 320hp - Hot Start Problem

[malibuparadise]

Like this one.

http://www.skidim.co...?number=49-5137

FWIW, I have had two of these fail in the last 2 years. High discharge pressure was how the first failed, and that kicked my butt during trouble shooting, as my reg carb kept flooding (now I have a fuel pressure gage downstream of the fuel pump---always a good idea IMO), and the next one had some kind of electrical problem-- working sometimes and not others-- a tron gremlin???, and after that I couldn't trust it and replaced it with the Holley marine fuel pump for reg carbs. Looks so much cooler too ;-)

Also, the design is suspect, IMO, because the electrical connections are mounted on the bottom and are press fit!!. with no way I could find to effectively tighten later...Since there is natural vibration in a boat due to many reasons (waves for one big one), this makes no sense to me. Also, it comes with a wire chink-a-daro fastener/holder that is also suspect...and probably a later addition after someone said, WTH....

[Cueball]

I'm with Steve B. on this one. Though it's not fixing the problem.....It's cheap and avoids the problem. If we run hard wakeboarding or skiing for an hour or two, then break for refreshments, I place a 4" x 4" block about 8-10" long under the edge of the engine cover. I keep it in the ski locker/cooler while not in use. It takes a bit to remember to do it........and make sure you remove it when you start back up for obvious safety reasons, but the problem goes away.

I've considered cutting holes in the sides of the engine cover to place vents there.......but I'm sure it would be much louder inside the boat while underway. Also, I just run 89 octane with no additives.

[dalt1]

FWIW, I have had two of these fail in the last 2 years. High discharge pressure was how the first failed, and that kicked my butt during trouble shooting, as my reg carb kept flooding (now I have a fuel pressure gage downstream of the fuel pump---always a good idea IMO), and the next one had some kind of electrical problem-- working sometimes and not others-- a tron gremlin???, and after that I couldn't trust it and replaced it with the Holley marine fuel pump for reg carbs. Looks so much cooler too ;-)

Also, the design is suspect, IMO, because the electrical connections are mounted on the bottom and are press fit!!. with no way I could find to effectively tighten later...Since there is natural vibration in a boat due to many reasons (waves for one big one), this makes no sense to me. Also, it comes with a wire chink-a-daro fastener/holder that is also suspect...and probably a later addition after someone said, WTH....

I put over 100 hrs on my set up this year and not 1 problem. I am very happy with it. I bought the Carter pump separate and wired it in myself. I think it cost me just over $100.

[dalt1]

I'm with Steve B. on this one. Though it's not fixing the problem.....It's cheap and avoids the problem. If we run hard wakeboarding or skiing for an hour or two, then break for refreshments, I place a 4" x 4" block about 8-10" long under the edge of the engine cover. I keep it in the ski locker/cooler while not in use. It takes a bit to remember to do it........and make sure you remove it when you start back up for obvious safety reasons, but the problem goes away.

I've considered cutting holes in the sides of the engine cover to place vents there.......but I'm sure it would be much louder inside the boat while underway. Also, I just run 89 octane with no additives.

I did cut some 2" holes in my side divider to help with cooling. As noted earlier in my posts, still had problems occasionally. Left center motor cover up also. So much nicer to have it fixed and not have to remember to open hatch and if it locks up then have to deal with getting her running again. Occasionally the cold water on the pump would not even get her going. Embarrassing to have to deal with this on a nice expensive boat.

[rdog]

Hi All,

So I took the boat out again yesterday after changing the ECT sensor and adding some premium fuel to the tank. It was 35*c yesterday so it was a good day to test out a true hot start.

We drove around for an hour or so and got it well up to temp then pulled into shore and let it sit for 30mins without opening the engine hood or the turning on the blower. After 30mins had passed I turned her over and this time it started but was really rough, I let it run for a minute but still running very rough. I engage gear and it conked out. After this it would not ignite again. When turning the key from off to ignition I could hear the fuel pump pumping as normal.

I then tried the wet towel on the fuel pump and fuel lines and tried to restart after a couple of minutes. Still no luck and would not ignite.

I then moved the key from off to ignition listening for the fuel pump. I could hear a funny noise at the end of its pump. The noise sounded like it was struggling to pump fuel as it was making a higher pitched ring (link below). I keep make the pump pump 6 or seven times until finally turning the key. Well, it started perfectly and run perfect....

This tells me based on everyone elses comments in the thread that either the fuel pump is playing up when hot or there is a vapor lock in the line and a second fuel pump maybe required...anyone else got any ideas or experienced this?

Thanks!

http://chilp.it/f2adfc

[dalt1]

Call me I will give you all I can remember about this battle.( I pm'd my # to you) In the end the vapor lock pump kit is what cured mine.

[shawndoggy]

From memory if the pump starts getting high pitched, it's either starting to fail or the screen/filter right in front of the pump is getting clogged.

[tvano]

I then moved the key from off to ignition listening for the fuel pump. I could hear a funny noise at the end of its pump. The noise sounded like it was struggling to pump fuel as it was making a higher pitched ring (link below). I keep make the pump pump 6 or seven times until finally turning the key. Well, it started perfectly and run perfect....

http://chilp.it/f2adfc

that 'higher pitched ring' made me think about another possibility.

that noise also occurs when the pump is starving because the inlet screen is plugged.

pull the feed hose at the pump and you will find a VERY hard to see screen up in the feed port.

if it gets clogged it can cause fuel problems.

[dalt1]

Or, the pump is full of vapors and not fluid, hence the Vapor lock.

[shawndoggy]

Or, the pump is full of vapors and not fluid, hence the Vapor lock.

Easily verified / tested by venting the schrader valve at the fuel rail to see if you get vapor or liquid, right?

Also, seems like a clogged screen wouldn't help the vapor lock problem in any event, since delivery of liquid fuel by way of the fuel pump is the "cure."

Edited December 9, 2012 by shawndoggy

[Sixball]

Hi All,

So I took the boat out again yesterday after changing the ECT sensor and adding some premium fuel to the tank. It was 35*c yesterday so it was a good day to test out a true hot start.

We drove around for an hour or so and got it well up to temp then pulled into shore and let it sit for 30mins without opening the engine hood or the turning on the blower. After 30mins had passed I turned her over and this time it started but was really rough, I let it run for a minute but still running very rough. I engage gear and it conked out. After this it would not ignite again. When turning the key from off to ignition I could hear the fuel pump pumping as normal.

I then tried the wet towel on the fuel pump and fuel lines and tried to restart after a couple of minutes. Still no luck and would not ignite.

I then moved the key from off to ignition listening for the fuel pump. I could hear a funny noise at the end of its pump. The noise sounded like it was struggling to pump fuel as it was making a higher pitched ring (link below). I keep make the pump pump 6 or seven times until finally turning the key. Well, it started perfectly and run perfect....

This tells me based on everyone elses comments in the thread that either the fuel pump is playing up when hot or there is a vapor lock in the line and a second fuel pump maybe required...anyone else got any ideas or experienced this?

Thanks!

http://chilp.it/f2adfc

Did you try what I said. Like I said I worked on a boat that had the same symptoms and chased my butt for months. when I finely checked the pressure switch Its worked for 4 years now and not missed a beat. It will take 10 minutes to try. you can try a flush on it and not spend a dime.

[rdog]

that 'higher pitched ring' made me think about another possibility.

that noise also occurs when the pump is starving because the inlet screen is plugged.

pull the feed hose at the pump and you will find a VERY hard to see screen up in the feed port.

if it gets clogged it can cause fuel problems.

Thanks I will take a look at this. Why would it only be when its hot though?

Easily verified / tested by venting the schrader valve at the fuel rail to see if you get vapor or liquid, right?

Where is this located & what does it look like? Will much fuel come out when opening this valve?

[rdog]

Did you try what I said. Like I said I worked on a boat that had the same symptoms and chased my butt for months. when I finely checked the pressure switch Its worked for 4 years now and not missed a beat. It will take 10 minutes to try. you can try a flush on it and not spend a dime.

Where is the pressure switch & what does it look like? I take it that this is different to the ECT sensor I already changed.

[dalt1]

Easily verified / tested by venting the schrader valve at the fuel rail to see if you get vapor or liquid, right?

Also, seems like a clogged screen wouldn't help the vapor lock problem in any event, since delivery of liquid fuel by way of the fuel pump is the "cure."

I ran my boat with a fuel gauge hooked to the Shrader valve while Fighting this gremlin. Could not tell if it was vapor or not when bleeding valve in locked condition. Still spewed fuel because I believe the pump was vapor and rails may not have been. Pump just couldn't push fuel in rails to recommended 60psi. Would run but very rough and cough to a stop if put in gear.

[Sixball]

I would look just above your oil filter you will find a pressure switch It is screwed into the side of the block. Mine has two wires at the end. You can unscrew it from the block and flush it with a cleaner. Its a pressure switch if it is hanging up it will cut spark to your engine. I found this to be the culprit and it did just what you are describing. The boat I worked on started cold every time but would give us problems well hot or even cut out just after take off well worm. I flushed one with gas as I had no cleaner at the time. It worked fine but its not a good practice to use gas for cleaning just for safety reasons. blow it out and reinstall it put the wires back on and give it a go.

I am betting you will be fine. the switch is not very costly if you wish to replace it but cleaning has worked every time for me.

I would think this is put on our boats so if we lose oil pressure we don't put rods out the side of the engine and through the haul. This can be bad but not show up on the boats oil pressure gage.

[malibuparadise]

I would think this is put on our boats so if we lose oil pressure we don't put rods out the side of the engine and through the haul. This can be bad but not show up on the boats oil pressure gage.

FWIW, I also thought one reason for this pressure switch, if I'm thnking same one you are(?), is that it's wired in line with the fuel pump, so with no oil pressure no fuel pumping... not good to have fuel pumping when engine isn't running.

[Bozboat]

Thanks I will take a look at this. Why would it only be when its hot though?

Where is this located & what does it look like? Will much fuel come out when opening this valve?

Located on the fuel line between fuel pump and fuel injector rail, it looks like a valve stem for a tire only metal, same type of press and release valve