DIY_EFI Digest Thursday, October 14 1999 Volume 04 : Number 579 In this issue: Re: marine engine FI Re: DIY_EFI Digest V4 #576 Re: DIY_EFI Digest V4 #576 Re: DIY_EFI Digest V4 #576 Re: DIY_EFI Digest V4 #576 See the end of the digest for information on subscribing to the DIY_EFI or DIY_EFI-Digest mailing lists. ---------------------------------------------------------------------- Date: Wed, 13 Oct 1999 12:35:54 -0700 (PDT) From: Stuart Hastings Subject: Re: marine engine FI > >Mercury uses a system they licensed from Orbital (of > >Australia), OMC bought a company named Ficht (of Germany), and Yamaha > >has developed their own. As I recall, Ficht uses a special injector > >that develops about 450psi, > > More like 200, IIRC. Also, Ficht's solenoid driven injector is not very > precise; the pressure varies a lot. I suppose there is no way to really know without measuring it, and this would be difficult. One imagines a small, closed chamber, filled with an incompressible liquid, and a Ficht injector screwed in one end. Perhaps you could repeatedly fire the injector until the pressure stopped rising... In any case, OMC has claimed "exceeding 500 psi" for their injectors (http://www.omc-online.com/pressreleases/pressreleases/pr488.htm). Yes, it's probably a meaningless figure. > >Orbital uses ~90psi mixed with a blast of > >compressed air, > > Note that compressed air contains far more energy than pressurized fuel, > which means that Orbital gets by with a far lower pressure. Thus, they avoid > a few of the drawbacks of DFI. Speaking as a potential customer, the extra belt and air compressor used on the Orbital design look like additional parts to break. The Ficht design has none of these parts. The other drawback to the Ficht injector (beyond the imprecision you mention) is its energy requirements. OMC redesigned and enlarged their alternators to supply 24V in order to drive those injectors (they'll start the engine on 12V). Orbital/Mercury and Yamaha get their energy via a belt, without the electrical losses. > >Curiously, while DFI reduces oil consumption, it doesn't really > >address the oil-emission question. > > DFI as such sure does; reduced consumption leads to lower emmissions, after all. > > Hower, due to technical problems, some current DFIs, and particularly > Mercury's, tend to use surprising quantities of oil. My point was that DFI two-stroke engines are still blowing oil out the exhaust. If the emissions have dropped by half, that's great, but it's still disconcerting. > >Apparently EPA agrees this is not a > >major pollution issue at this time. More specifically, EPA is interested only in *air* pollution from marine engines. When they mandated oxygenated fuel, they indirectly required California fuel to incorporate MTBE, and nobody realized it would contaminate the *water*. Hello, EPA, most marine engines exhaust *underwater*, even if most of their smog immediately bubbles to the surface! I'll guess that EPA isn't yet concerned about oil emissions because much of the oil stays in (or on the surface of) the *water*. > And quite a few customers are on their second, third or fourth power head on > warranty... OMC's Ficht has been worse off than Mercury, in this > respect. OMC claims to have fixed their problems, and I haven't heard of any Ficht owners out of warranty yet. > (Mercury found unexpected problems and quietly pulled back their first > generation of DFI's, and came back with an improved design and a new name. > OMC on the other hand, being somewhat financially challenged, let their > customers do the testing for them, to the misfortune of a whole lot of > people. OMC also had an Orbital license, and built but never sold an engine > almost identical to Mercury's original DFI, by the way) OMC has said as much on their website in the past. They also listed a bunch of problems they had with it, all problems that were adequately solved by Mercury. This leads me to believe they prefer Ficht because they were able to buy the technology outright and avoid paying royalties. stuart hastings ------------------------------ Date: Tue, 12 Oct 1999 23:56:14 +0200 From: "Espen Hilde" Subject: Re: DIY_EFI Digest V4 #576 Thanks Stuart for a interesting summary. Yamahas new (High pressure direct injection) HPDI 200hp is better than the 75% reduction in certain emissions the Environmental protection agency requires by 2006. It has a new engine block with longer stroke and 76-degree v 6. They want to make the engine slimmer to not get into trubbles with the boat manufacturers. To reduce the fuel to a fine mist the system uses high pressure, 700psi , ficht uses (OMC) 300-400psi , DFI (Merc) 80 psi. The pressure is developed through a very small high speed pump. Two stainless steel fuel rails for each cyl row. The Injectors looks very simular to car efi injectors....... They say that the high pressure is a part of the whole picture, without the high pressure they could not use internal opening style injectors, the pressure keeps them closed when they need to be closed. Internal opening style injectors that dont protrude into the combustion chamber are,unique to the HPDI system. They clame that the most notable advantage is that they dont impede or disrupt the fuel flume. Like diesel style injectors vs. efi injectors. Yamaha uses the common sensors , crank position sensor.TPS,KNOK, rpm sensor, water temp, air temp,MAP,O2.....o2.............?(patented 02 sensors ) All manufacturers of theese dfi outboard engines has had some bugs that develop..... A lake in US has abandoned all engines that are not to the latest eviromental standards......If you want to take your boat with your old twostroke engine out , you have to change your engine to a new one first. Mercury delivers a high perf 200 dfi that took 2 place at paris ruoen 24 hour (river) race.The ability to run lean burn conditions is great for reliability as I see it. I have 2 2.5efi high performance engines that I am reparing, line boring new crank, one piston 70grams to heavy +++ They have analog efi with old d-jetronic peek and hold injectors.(As standard) The new 2.5 efis has digital boxes ,Motorolabased. Any who has any info on them?(GM?) I hope to put another efi system om my engines and run LPG....... Liquid injecting. Any input is appreciated. To afford to use it....... Espen Hilde ------------------------------ Date: Tue, 12 Oct 1999 23:56:14 +0200 From: "Espen Hilde" Subject: Re: DIY_EFI Digest V4 #576 Thanks Stuart for a interesting summary. Yamahas new (High pressure direct injection) HPDI 200hp is better than the 75% reduction in certain emissions the Environmental protection agency requires by 2006. It has a new engine block with longer stroke and 76-degree v 6. They want to make the engine slimmer to not get into trubbles with the boat manufacturers. To reduce the fuel to a fine mist the system uses high pressure, 700psi , ficht uses (OMC) 300-400psi , DFI (Merc) 80 psi. The pressure is developed through a very small high speed pump. Two stainless steel fuel rails for each cyl row. The Injectors looks very simular to car efi injectors....... They say that the high pressure is a part of the whole picture, without the high pressure they could not use internal opening style injectors, the pressure keeps them closed when they need to be closed. Internal opening style injectors that dont protrude into the combustion chamber are,unique to the HPDI system. They clame that the most notable advantage is that they dont impede or disrupt the fuel flume. Like diesel style injectors vs. efi injectors. Yamaha uses the common sensors , crank position sensor.TPS,KNOK, rpm sensor, water temp, air temp,MAP,O2.....o2.............?(patented 02 sensors ) All manufacturers of theese dfi outboard engines has had some bugs that develop..... A lake in US has abandoned all engines that are not to the latest eviromental standards......If you want to take your boat with your old twostroke engine out , you have to change your engine to a new one first. Mercury delivers a high perf 200 dfi that took 2 place at paris ruoen 24 hour (river) race.The ability to run lean burn conditions is great for reliability as I see it. I have 2 2.5efi high performance engines that I am reparing, line boring new crank, one piston 70grams to heavy +++ They have analog efi with old d-jetronic peek and hold injectors.(As standard) The new 2.5 efis has digital boxes ,Motorolabased. Any who has any info on them?(GM?) I hope to put another efi system om my engines and run LPG....... Liquid injecting. Any input is appreciated. To afford to use it....... Espen Hilde ------------------------------ Date: Tue, 12 Oct 1999 23:56:14 +0200 From: "Espen Hilde" Subject: Re: DIY_EFI Digest V4 #576 Thanks Stuart for a interesting summary. Yamahas new (High pressure direct injection) HPDI 200hp is better than the 75% reduction in certain emissions the Environmental protection agency requires by 2006. It has a new engine block with longer stroke and 76-degree v 6. They want to make the engine slimmer to not get into trubbles with the boat manufacturers. To reduce the fuel to a fine mist the system uses high pressure, 700psi , ficht uses (OMC) 300-400psi , DFI (Merc) 80 psi. The pressure is developed through a very small high speed pump. Two stainless steel fuel rails for each cyl row. The Injectors looks very simular to car efi injectors....... They say that the high pressure is a part of the whole picture, without the high pressure they could not use internal opening style injectors, the pressure keeps them closed when they need to be closed. Internal opening style injectors that dont protrude into the combustion chamber are,unique to the HPDI system. They clame that the most notable advantage is that they dont impede or disrupt the fuel flume. Like diesel style injectors vs. efi injectors. Yamaha uses the common sensors , crank position sensor.TPS,KNOK, rpm sensor, water temp, air temp,MAP,O2.....o2.............?(patented 02 sensors ) All manufacturers of theese dfi outboard engines has had some bugs that develop..... A lake in US has abandoned all engines that are not to the latest eviromental standards......If you want to take your boat with your old twostroke engine out , you have to change your engine to a new one first. Mercury delivers a high perf 200 dfi that took 2 place at paris ruoen 24 hour (river) race.The ability to run lean burn conditions is great for reliability as I see it. I have 2 2.5efi high performance engines that I am reparing, line boring new crank, one piston 70grams to heavy +++ They have analog efi with old d-jetronic peek and hold injectors.(As standard) The new 2.5 efis has digital boxes ,Motorolabased. Any who has any info on them?(GM?) I hope to put another efi system om my engines and run LPG....... Liquid injecting. Any input is appreciated. To afford to use it....... Espen Hilde ------------------------------ Date: Tue, 12 Oct 1999 23:56:14 +0200 From: "Espen Hilde" Subject: Re: DIY_EFI Digest V4 #576 Thanks Stuart for a interesting summary. Yamahas new (High pressure direct injection) HPDI 200hp is better than the 75% reduction in certain emissions the Environmental protection agency requires by 2006. It has a new engine block with longer stroke and 76-degree v 6. They want to make the engine slimmer to not get into trubbles with the boat manufacturers. To reduce the fuel to a fine mist the system uses high pressure, 700psi , ficht uses (OMC) 300-400psi , DFI (Merc) 80 psi. The pressure is developed through a very small high speed pump. Two stainless steel fuel rails for each cyl row. The Injectors looks very simular to car efi injectors....... They say that the high pressure is a part of the whole picture, without the high pressure they could not use internal opening style injectors, the pressure keeps them closed when they need to be closed. Internal opening style injectors that dont protrude into the combustion chamber are,unique to the HPDI system. They clame that the most notable advantage is that they dont impede or disrupt the fuel flume. Like diesel style injectors vs. efi injectors. Yamaha uses the common sensors , crank position sensor.TPS,KNOK, rpm sensor, water temp, air temp,MAP,O2.....o2.............?(patented 02 sensors ) All manufacturers of theese dfi outboard engines has had some bugs that develop..... A lake in US has abandoned all engines that are not to the latest eviromental standards......If you want to take your boat with your old twostroke engine out , you have to change your engine to a new one first. Mercury delivers a high perf 200 dfi that took 2 place at paris ruoen 24 hour (river) race.The ability to run lean burn conditions is great for reliability as I see it. I have 2 2.5efi high performance engines that I am reparing, line boring new crank, one piston 70grams to heavy +++ They have analog efi with old d-jetronic peek and hold injectors.(As standard) The new 2.5 efis has digital boxes ,Motorolabased. Any who has any info on them?(GM?) I hope to put another efi system om my engines and run LPG....... Liquid injecting. Any input is appreciated. To afford to use it....... Espen Hilde ------------------------------ End of DIY_EFI Digest V4 #579 ***************************** To subscribe to DIY_EFI-Digest, send the command: subscribe diy_efi-digest in the body of a message to "Majordomo@xxx. A non-digest (direct mail) version of this list is also available; to subscribe to that instead, replace "diy_efi-digest" in the command above with "diy_efi".