mbuk Posted May 3, 2012 Share Posted May 3, 2012 hi allHave a E7-427 Vmac II. When I start it cold, white smoke exits the exhaust. I guess, it shoots out remaining fuel which remains in one or more cylinders.I check the pump and the nozzels. Everything is ok. Running warm, it smoke black, not excecive, but rather constantly. The Mpga is down a lotrecently. Changed filters, got rid of the whater tramp. It is still bad. The ECM doesnt show a failure.Thanks for your input.Marcel Quote Link to comment https://www.bigmacktrucks.com/topic/24912-e7-427-vmac-ii-black-smoke/ Share on other sites More sharing options...
Mackpro Posted May 3, 2012 Share Posted May 3, 2012 White smoke is normal on start up on the VMAC 1's and 2's as the timing advance is powered by oil pressure and of course when you first start engine it takes alittle while to get the timing advance moving. On the black smoke, everything on the turbo boost side. After cooler, intake manifold gaskets, dirty air filter. Black smoke is unburnt fuel, Either from to much fuel or lack of air/boost. Quote Link to comment https://www.bigmacktrucks.com/topic/24912-e7-427-vmac-ii-black-smoke/#findComment-117476 Share on other sites More sharing options...
theakerstwo Posted May 3, 2012 Share Posted May 3, 2012 What he said. Quote glenn akers Link to comment https://www.bigmacktrucks.com/topic/24912-e7-427-vmac-ii-black-smoke/#findComment-117565 Share on other sites More sharing options...
mbuk Posted May 4, 2012 Author Share Posted May 4, 2012 I changed the manifold pressure gauge as the old one didnt work. It newer showes more than 20 psi.Shouldnt it go up to 30 - 35 under heavy pressure? Quote Link to comment https://www.bigmacktrucks.com/topic/24912-e7-427-vmac-ii-black-smoke/#findComment-117694 Share on other sites More sharing options...
Mackpro Posted May 4, 2012 Share Posted May 4, 2012 I changed the manifold pressure gauge as the old one didnt work. It newer showes more than 20 psi.Shouldnt it go up to 30 - 35 under heavy pressure?For a 1995 427HP VMAC2 the book says 24-32 psi is where it should be. Quote Link to comment https://www.bigmacktrucks.com/topic/24912-e7-427-vmac-ii-black-smoke/#findComment-117702 Share on other sites More sharing options...
Lmackattack Posted May 4, 2012 Share Posted May 4, 2012 I would say 20 is a little to low at full load. I had a simmalr problem with a mechanical engine. 16 psi Max under load.was smoking all the time. I Found that My turbo housing was melting away and the exhaust was bypassing the blades of the impeller. I put a new/used turbo on and she now puts down 27PSI. and only smokes if there is no boost. I say search for an boost issue or a leak in the intake system. Quote Link to comment https://www.bigmacktrucks.com/topic/24912-e7-427-vmac-ii-black-smoke/#findComment-117706 Share on other sites More sharing options...
mbuk Posted May 5, 2012 Author Share Posted May 5, 2012 I checked the cooler. It had 4 cracks. So I went for a repair. Now, the cooler is fin but the pressure gauge still not passes 20. I guess next step should be the turbo. Thats a problem, over here in the Dominican Republic there are a lot of guyswhich sell used parts. How can I be sure if the "new" one works better as they dont give any guarantees. Isnt it better torepair the old one? How can I check it first, maybe its doing fine and another problem is causing low intake pressure. Quote Link to comment https://www.bigmacktrucks.com/topic/24912-e7-427-vmac-ii-black-smoke/#findComment-117875 Share on other sites More sharing options...
mbuk Posted May 17, 2012 Author Share Posted May 17, 2012 the problem is not solved yet, the turbo is fine. could it be that the econo advance is bad? the ecm doesnt send a code Quote Link to comment https://www.bigmacktrucks.com/topic/24912-e7-427-vmac-ii-black-smoke/#findComment-119728 Share on other sites More sharing options...
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