Re: Help, Mercruiser 4.2L D-Tronic wont rev past 2500rpm
hi thanks for your reply, bellow is some info I have just emailed to Cummins uk, yes they finally got back to me, but were not familliar with the fuel system as the mew CMD engines use common rail
Hi Alan,
further to our conversation
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I have had this engine fitted for 2 years and spent a lot of time and money to get it fixed, but it still wont rev past 2500rpm under load, no one seems to know anything about it , since the engine was fitted it has had a brand new loom & harness, new sensors all round (except fuel shut off solinoid for limp mode), new #1 injector, re-built turbo (as the turbo bearings had failed and veins were scraping the housing). new wastegate valve (as the old one had seized and badly corroded) , new ecm the (engine was bare engine which had sat at Barrus for a couple of years) Bosch part number0 281 014 229, but it still wont go past 2500 rpm, it is fitted in a 1991 Bayliner 2556 command bridge (gross weight with fuel & water 4.2 ton) 9'6" Beam,with a brand new Bravo diesel X 2.1 ratio, origionaly fitted with 22" props, re-fitted with 20"props and no change at all, and has had a new stainless steel fuel tank made (no contamination), I have had the engine read with the diagnostics tool on several occasions and no faults are present (Rinda), and no warning light has come on (brand new dash and gauges), after I reconditioned the turbo, the top speed increased from 7mph to 9.8mph, with the Rinder attached and under load the engine runs fine upto 2500 rpm and throttle position sensor is showing correct position upto that point but as soon as it reaches 2500 rpm the engine wont increase bot this throttle position sensor continues upto 100% in line with the throttle position, engine idles at between 600 and 800 rpm, flywheel rpm is same as tacho, no problem there, when I disconected both feed and return (fuel lines are diesel suction fuel lines wo they wont colapse,with internal diameter of about 10mm) from the fuel tank and run the engine from a 5 gallon drum (at same height as the engine and at 1 metre distance from lift pump) at 1000 rpm in neutral fuel return was about 1 litre every 2 mins, when at 2500rpm return was less than this, when in drydock (with water attached) engine will run both in neutral and gear throughout the engine range with no problem, the engine dosn't apear to be strugling at all, but apears to be running in limp mode as far as fuel is concearned, could you confirm if 2 diferent types of fuel shut off solidoids 803623 were manufactured as I have been informed that one engages with a + feed and one engages with a negative, also do you know of any failiures conected with this solinoid, and any failiures conected with the lift pump including symptoms I am running out of ideas, patients and money, can you help?
flywheel rated at 300hp WOT around 3800rpm, it has the smallest props avilable fitted, since found that the previous owner couldn't get engine to run right either, the engine was manufactured in 2002, and was first used by Barrus Uk (main importer) in a large rib for show purposes, the engine was the sold and returned to Barrus where it sat for a few years , at which time it had parts taken from it which explains wht it was supplied to me through a mercruiser dealer with all new parts!
please help if you can
