efi wiring
#1
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I had distributor problems on my 98 Doral cabin cruiser with 5.7 efi mercruiser. I replaced the distributor with a two wire self contained distributor but now the fuel injectors do not spit fuel. I am assuming that there needs to be a connection made to the tach wire to tell the system that the engine is turning over. can somebody help me out with a wiring diagram or knowledge if this is even possible to run together. Thanks in advance
#2
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From: KY
I had distributor problems on my 98 Doral cabin cruiser with 5.7 efi mercruiser. I replaced the distributor with a two wire self contained distributor but now the fuel injectors do not spit fuel. I am assuming that there needs to be a connection made to the tach wire to tell the system that the engine is turning over. can somebody help me out with a wiring diagram or knowledge if this is even possible to run together. Thanks in advance
First what is your engine serial number?
#3
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0L012262. update. replaced the two barrel efi with Edelbrock manifold and 1409 carb. the old tub just won't plane out hardly at all. most of the time it plows at about 15 mph but occasionally I can get it over 20 then it planes out and will run up to close to 30. I know it's a lot of boat for a 5.7 but surely to god it would plane out from the factory. could use bottom paint and the trim tabs don't work but still think should plane out better. any suggestions. we are using a dui distributor also. we timed it at 12 deg at idle.
Last edited by diamondk; 07-22-2020 at 02:05 PM.
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It blew a head gasket first. we fixed that then it would plane out decent but developed a problem where it would die after it ran for a half hour or so. It would lose spark then after it cooled it would start and run decent for another 15 minutes and repeat the process. I am a diesel mechanic by trade but haven't messed with gas too much. I bought a new coil and distributor from amazon and replaced it with aftermarket of same style. we never could get it to run after that so decided to just go old school and got a Davis unified ignition coil in cap distributor, Edelbrock intake and carb and installed it. I thought that would be a power upgrade from a two barrel throttle body injection system but so far can't really get the power I need. It is a lot of boat for a 5.7 but Im sure its capable or they wouldn't have put it in from the factory and it did plane out for the short period I had it running correctly.
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#8
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From: Tampa Bay Area Florida/ North Miami Florida
You have too many variables at this point thats why you are not getting a lot of responses. Anyway I think timing should be no more than 10. Not sure what Ign you have or if it has a knock sensor but if it does at 12 Degress it is probably knocking and a knock sensor would pull power.
#9
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You have too many variables at this point thats why you are not getting a lot of responses. Anyway I think timing should be no more than 10. Not sure what Ign you have or if it has a knock sensor but if it does at 12 Degress it is probably knocking and a knock sensor would pull power.



