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Is it me or the Dealer ??
Looking for opinions; and to keep a fairly long story short I'll just indicate the major points. Formula 27PC, weights 10000 lb, replaced carbureted 454 with a 502 crate motor, obtained Mercruiser EFI system off Ebay which came from a twin engine setup, uses the VST fuel pump. EFI was dropped off UPS truck and damaged throttle body linkage and set screw stops. Had machine shop fabricate new linkage from aluminum and replace stop screws. Reset idle with procedure found on internet.
Boat performs well with WOT at 5200 RPM and 45MPH. Engine runs rich at idle will fowl plugs about every two years or so. Black soot seen around through hull exhaust tips and smell of fuel at idle. Replaced plugs, cap and rotor fall of 2010, plugs had quite a bit of build up. Current day - boat would not come up on plane and would only obtain 2900 RPM at WOT. Wanted the bottom repainted and looked for a "Premier" Mercruiser dealer with the hope they could tell me what the problem was. Told Service Manager (SM) what it was doing and spent 20 minutes about were the engine came from and its history. SM wrote down one line about the engine on the work order (boat would only obtain 2900 RPM). Dealer took it out for test run, found the knock sensor was retarding the engine. Dealer accomplished a compression test, replaced plugs, cap, rotor and plug wires. When asked about it running rich SM said the running rich was probably from a bad plug wire. Boat preformed like before and had a few times of running before season ended. During winterizing this year I found a new coil wire in the bilge and noticed my old one was used instead. Pulled plugs 1,3,5 and found they were pretty black, not gray. Ask SM about the coil wire and he said the technician probably thought the set didn't come with one. When asked about the black plugs the SM said his shop foremen said that was due to idling. There is more discussion but these are the high points in regard to the engine. My thoughts - Who buys a plug wire set and doesn't expect to get a coil wire? Have had several boats and never had one turn plugs black and smell fuel like this one. Never heard of a stock engine turning plugs black from idling in/out of no wake zone. |
Originally Posted by AllDodge
(Post 3823461)
Looking for opinions; and to keep a fairly long story short I'll just indicate the major points. Formula 27PC, weights 10000 lb, replaced carbureted 454 with a 502 crate motor, obtained Mercruiser EFI system off Ebay which came from a twin engine setup, uses the VST fuel pump. EFI was dropped off UPS truck and damaged throttle body linkage and set screw stops. Had machine shop fabricate new linkage from aluminum and replace stop screws. Reset idle with procedure found on internet.
Boat performs well with WOT at 5200 RPM and 45MPH. Engine runs rich at idle will fowl plugs about every two years or so. Black soot seen around through hull exhaust tips and smell of fuel at idle. Replaced plugs, cap and rotor fall of 2010, plugs had quite a bit of build up. Current day - boat would not come up on plane and would only obtain 2900 RPM at WOT. Wanted the bottom repainted and looked for a "Premier" Mercruiser dealer with the hope they could tell me what the problem was. Told Service Manager (SM) what it was doing and spent 20 minutes about were the engine came from and its history. SM wrote down one line about the engine on the work order (boat would only obtain 2900 RPM). Dealer took it out for test run, found the knock sensor was retarding the engine. Dealer accomplished a compression test, replaced plugs, cap, rotor and plug wires. When asked about it running rich SM said the running rich was probably from a bad plug wire. Boat preformed like before and had a few times of running before season ended. During winterizing this year I found a new coil wire in the bilge and noticed my old one was used instead. Pulled plugs 1,3,5 and found they were pretty black, not gray. Ask SM about the coil wire and he said the technician probably thought the set didn't come with one. When asked about the black plugs the SM said his shop foremen said that was due to idling. There is more discussion but these are the high points in regard to the engine. My thoughts - Who buys a plug wire set and doesn't expect to get a coil wire? Have had several boats and never had one turn plugs black and smell fuel like this one. Never heard of a stock engine turning plugs black from idling in/out of no wake zone. Why wasn't the linkage replaced with a stock part? Was the crate engine exactly the same as the engine the merc efi system was designed for? Me, I would send the ecm off to dustin at whipple or marc at precision pmefi.com to clean up your low end problem. The stock program from merc was far from perfect. |
Sounds like a timing issue. Check the timing and set to factory spec.. I think its 8 degrees. There is a procedure to put the computer into a mode to adjust base timing. Involves a paper clip. Do a search on here for paper clip base timing. Next up is Check the IAC with an ohm meter and shop manual for #'s or replace it if you don't have the ohm meter and manual. Use a Mercury IAC. Also might replace the coil with a high output from MSD.. These things wont break the bank and are probably cheaper than a trip to the shop.. If that does not fix it then it needs to go the shop and be diagnosed with a computer and will probably cost ya some $$$. Only other thing I can think of is Fuel injectors could be dirty.. Not something you can do yourself.. Need to remove them and send to www.pmefi.com
for testing and cleaning.. If you send it to them send the computer with it. Chris |
Originally Posted by 4bus
(Post 3823472)
What fault are you putting on the dealer? The coil wire? At least he was honest about it.
Why wasn't the linkage replaced with a stock part? Was the crate engine exactly the same as the engine the merc efi system was designed for? Me, I would send the ecm off to dustin at whipple or marc at precision pmefi.com to clean up your low end problem. The stock program from merc was far from perfect. You have to buy the entire throttle body (over 1K) linkage not sold by Merc. Machine shop did a great job matching the item. Linkage used to open secondary. Crate engine was twin 502 MPI, removed to install blowers. If sending off the ECM would fix the issue would be glad to do it.
Originally Posted by Blueabyss
(Post 3823478)
Sounds like a timing issue. Check the timing and set to factory spec.. I think its 8 degrees. There is a procedure to put the computer into a mode to adjust base timing. Involves a paper clip. Do a search on here for paper clip base timing. Next up is Check the IAC with an ohm meter and shop manual for #'s or replace it if you don't have the ohm meter and manual. Use a Mercury IAC. Also might replace the coil with a high output from MSD.. These things wont break the bank and are probably cheaper than a trip to the shop.. If that does not fix it then it needs to go the shop and be diagnosed with a computer and will probably cost ya some $$$. Only other thing I can think of is Fuel injectors could be dirty.. Not something you can do yourself.. Need to remove them and send to www.pmefi.com
for testing and cleaning.. If you send it to them send the computer with it. Chris My overall big question is I was expecting a Premier Merc Dealer to be able to find the issue or explain why my engine is running rich. This is the reason I took it to them, but so far I have no fix or answers only out quite a bid of cash. |
sending your ecu off isn't going to fix anything. You have something else going on here. Make sure your VST or Mechanical fuel pump are in proper operating condition.
search VST and you will find a great deal about diagnostics and common issues. |
You expected too much out of the dealer. They got it back to full rpm potential assumed it fixed the issue and gave it back to you.
I see stuff like this all the time. I sent an excursion to a reputable alignment shop after replacing all the tie rods, it was driven there, all it needed was a slight toe adjustment, the "expert" alignment tech sent it out the door with the wheel one full turn off to the left...... And said I installed the parts wrong. I fixed it in the customers driveway in 5 min....... If you want it done right do it yourself |
pull the vacume line off the fuel regulator and see of fuel comes out of the vacume end..if it dont have one then do a fuel pressure test,,if its over 43psi then its too high,,also make sure the engine is getting to operating temps,,it will think its still in start up mode and will run rich,,160* to 180* should be normal under load..
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Originally Posted by tunertech
(Post 3823642)
sending your ecu off isn't going to fix anything. You have something else going on here. Make sure your VST or Mechanical fuel pump are in proper operating condition.
search VST and you will find a great deal about diagnostics and common issues.
Originally Posted by lil red
(Post 3823653)
You expected too much out of the dealer. They got it back to full rpm potential assumed it fixed the issue and gave it back to you.
I see stuff like this all the time. I sent an excursion to a reputable alignment shop after replacing all the tie rods, it was driven there, all it needed was a slight toe adjustment, the "expert" alignment tech sent it out the door with the wheel one full turn off to the left...... And said I installed the parts wrong. I fixed it in the customers driveway in 5 min....... If you want it done right do it yourself
Originally Posted by mrfixxall
(Post 3823655)
pull the vacume line off the fuel regulator and see of fuel comes out of the vacume end..if it dont have one then do a fuel pressure test,,if its over 43psi then its too high,,also make sure the engine is getting to operating temps,,it will think its still in start up mode and will run rich,,160* to 180* should be normal under load..
Wonder how these so called premier dealers get their premier status? Maybe how many folks they fool successfully |
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You stated that they were crate engines. Did they come from Merc? If not, they probably do not have the same cam as a Merc. 502 MPI. That alone will throw the tune out in left field.
If it's idling at the correct rpm and just rich, then there is nothing wrong with the IAC. If the IAC was acting up, it would not idle correctly. Verify that the fuel pressure is correct. Check to be sure the ignition components are in good shape. If that is all good, then my suggestion would be to get an O2 sensor in it and see what the AFR's are. If it's rich, it will show it. You will need to install O2 bungs in the exhaust pipes in order to use a wideband O2 sensor. Also, see if there is any way that you can verify what camshaft is in the engine. Eddie |
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