6.2 to 6.5 ALOT of white smoke

[engineeradam]

I had a NA 6.2 that cracked a crank. I got a 6.5 long block from a buddy that was out of a turbo truck. I swapped on all of the 6.2 parts and MFI IP pump, so now its a NA 6.5. PS; i turned the IP pressure up an 1/8th turn in hopes to give the 6.5 a little more life.

Heres the problem; It starts and idles extremely rough with ALOT of white smoke. I have "fiddled" with the timing with no gain. Is it possible the timing marks on the IP gear on a turbo is more retarded then on a NA? What is my best place to start? Fuel return? Feed? Injectors? IS there a lobe on the cam on the 6.5s that is running my mech. pickup pump? Or is the IP trying to draw from the tank?


Any help is much appreciated, im gonna go back at it again in the morning, starting with fuel feed unless you guys point me in another direction

[More Power]

I had a NA 6.2 that cracked a crank. I got a 6.5 long block from a buddy that was out of a turbo truck. I swapped on all of the 6.2 parts and MFI IP pump, so now its a NA 6.5. PS; i turned the IP pressure up an 1/8th turn in hopes to give the 6.5 a little more life.

Heres the problem; It starts and idles extremely rough with ALOT of white smoke. I have "fiddled" with the timing with no gain. Is it possible the timing marks on the IP gear on a turbo is more retarded then on a NA? What is my best place to start? Fuel return? Feed? Injectors? IS there a lobe on the cam on the 6.5s that is running my mech. pickup pump? Or is the IP trying to draw from the tank?


Any help is much appreciated, im gonna go back at it again in the morning, starting with fuel feed unless you guys point me in another direction

I recommend using an EGT gauge to help adjust fuel-rate. It's exhaust temperature that helps you decide whether there's enough fuel. Some pumps aren't able to deliver more fuel because of wear or because it's already near its max. Some higher-mile pumps produce symptoms of smoke or surging when pushed past its maximum fuel rate.

If the engine will run, timing is close. A tooth off in either the cam sprockets or IP gears will require the injection pump to cranked over nearly as far as it can go in one direction to allow the engine run - sort of.

All of these 6.2/6.5 engines use the same cam, as far as I know. This means they all have the mechanical lift pump lobe on the cam. Is the lift pump generating fuel pressure?



I got a 6.5 long block from a buddy that was out of a turbo truck.


There usually a reason why an engine was removed from a truck. Barring a wreck, I'd want to know more about why the engine was removed. Good running engines don't sit around long. Jim

[engineeradam]

i have an egt gauge, but it isnt running good enough to drive. Im lucky if it idles.

The IP pump ran the previous 6.2 flawlessly.

The pickup pump is generating pressure.

I pressurized the fuel system with a modified fuel cap and no obvious leaks.

I tore the engine down and cleaned all the valves and ports and rebuilt with new gaskets. The intake ports were so clogged (PROB faulty CDR) that the engine prob ran like crap, thats my guess on why it was parked.

The white smoke is pretty even out of both exhausts (TRUE DUALS) so i dunno if changing the nozzles would be to my benefit. How can i test the IP? I cannot afford a new one.

[DmaxMaverick]

Does it have EGR? If so, it's highly suspect. Also, the source of a gooey intake, more so than the CDR.

[engineeradam]

nope, no egr, and i also have the jcode intake.

[engineeradam]

i changed the injectors down one bank, with no luck. both sides still smoking away. I checked each injector too; by cranking the engine without them in the cylinders, and i had a nice spray from them all.

Is it possible that i should turn the fuel pressure back down?? That doesnt make sense to me being a 6.2 pump on a 6.5 engine.

[engineeradam]

I turned the IP back down. Seems to run alot better. But theres a valve knock. Any ideas what it is? The valves are on a rocker system unlike a gasser, so whats the likely cause? The hydraulic lifter? Any ideas are helpful. Ill pull the valve cover off tomorrow, its way to cold tonight