PDA

View Full Version : PCV re-route LMM ?



D_R_C
09-24-2008, 08:19
Does anyone know if doing a PVC re-route would cause any emission or engine issues,and your opinions.
Also would doing this lead to warranty problems ???

DmaxMaverick
09-24-2008, 08:36
Could be a huge problem, or no problem at all. Depends on where you are routing to. Warranty could be an issue, but only if the function of the PCV or other system is defeated or diminished. I'd be more concerned with crankcase pressure management.

Where would you route it to, and why? If outside the "closed system", that would be considered an emissions modification, and could certainly effect warranty claims (among some legal issues, similar to removing the cat). If you want to reduce/eliminate oil vapor condensation in the CAC, you're not going to get anywhere w/o moving away from the closed system. A condenser/capture system would be your only option.

More Power
09-24-2008, 08:52
I see where BD is selling a "a crankcase vent condenser/capture system" for the Ford & Dodge diesels. The LB7 had one from the factory. The crankcase gases, when using these systems, ultimately vent to atmosphere, which would (as DM indicated) be an emissions system modification, and possibly cause warranty/legal issues.

Before switching to an open type vent system, I'd want to know more about the PCV valves used by the newer Duramax. If they are the same as those used by the LB7, there wouldn't be a problem with crankcase pressure management.

Jim

D_R_C
09-24-2008, 09:18
The system I was looking at does vent to the atmosphere,pretty much the same as the older d-max`s.
The concern I have is from the past on my ex 03 Ford 6.0 when I removed the intake(doing mods)the turbo impeller vains was caked with oil and slime. Oil film was always seeping out of the turbo hoses to and from the intercooler.
And it did have a lot of blow-by,this was at 25K miles,after I did the PVC re-route mod.

Kennedy
09-24-2008, 18:24
I left the PCV system stock on both my 2005 and 2007. Closed PCV certainly doesn't help, but I don't think it's really that bad EXCEPT when combined with EGR. I think the EGR system is far more evil...

Duramaster
09-25-2008, 06:36
it might also affect MAF values? I haven't messed around with that, but I suppose you could monitor the MAF values to see if anything changes when the tube is disconnected from the rocker cover.

D_R_C
09-25-2008, 12:54
I left the PCV system stock on both my 2005 and 2007. Closed PCV certainly doesn't help, but I don't think it's really that bad EXCEPT when combined with EGR. I think the EGR system is far more evil...

I was not thinking of closing the PVC. That would be foolish,but I`m sure some has done that and blew out some seals.
Capping the intake at the turbo and venting from both valve covers out,like the older diesels, this was just my thoughts.
I`m getting old and somewhat disabled,this will probably be my last truck.
Maybe this LMM does not have as much blow-by as my ex 03 Ford 6.0 which gunked up the turbo vains.

More Power
09-25-2008, 22:36
Recycling crankcase gases back into the intake system results in an oil film inside the turbo compressor, the intercooler and the intake manifold.

This oil film can collect soot as the EGR operates. We've seen 6.5's that had significant buildup inside the intake manifold, which was restricting intake air flows.

An oil film also acts as a minor thermal barrier inside the intercooler, which reduces the efficiency of the intercooler by a some amount.

Jim

Kennedy
09-26-2008, 07:25
I was not thinking of closing the PVC. That would be foolish,but I`m sure some has done that and blew out some seals.
Capping the intake at the turbo and venting from both valve covers out,like the older diesels, this was just my thoughts.
I`m getting old and somewhat disabled,this will probably be my last truck.
Maybe this LMM does not have as much blow-by as my ex 03 Ford 6.0 which gunked up the turbo vains.

To clarify: The OE system is closed. It draws out the gasses and recycles them. A bit of oil film, while not exactly optimum isn't really a big concern to me. Add EGR and then it's a mess. The LB7 had an open system, BUT there was a collector to help gather the majority of oil vapors, condense them, and return to the oil pan.

What I might consider doing if I were to mod one of these would be to build an evac system like you's see on a race engine with headers.

You'd essentially slash cut (45°) a 1/2" galv pipe nipple and insert into the center of the post turbo exhaust pipe at a 45° angle with the flow. The slash cut opening would then be oriented to the rear. The flow of exhaust gasses can then put a slight negative pressure on the system under the right conditions. A simple check valve like from an old gas engine with EGR/AIR is used to adapt to the hose and keep serious backflow from occurring.

I built a similar setup (less the check valve) with the exhaust from my central vac into the pipe from my radon fan (post fan) and it works very well.

D_R_C
09-26-2008, 08:06
Thanks everyone for the input,now I just need to do something with the gasses IF I end up doing this mod.
Thanks again for the feed back.

Dakster
09-29-2008, 17:23
Please don't compare the Duramax to a Ford 6.Ohh S*^&

I had one and as many problems as I am having with the Durmax, it is nothing compared to my 2003 Ford Excursion 6.0 Diesel that the dealer couldn't keep running long enough for me to get it home...

D_R_C
09-30-2008, 12:36
Please don't compare the Duramax to a Ford 6.Ohh S*^&

I had one and as many problems as I am having with the Durmax, it is nothing compared to my 2003 Ford Excursion 6.0 Diesel that the dealer couldn't keep running long enough for me to get it home...

I was not compairing the powerstroke to Dmax just discussing crankcase blow-by,which I`m pretty sure the 6.0 is bad with blow-by.
The main difference I`m seeing so far is,I`m not in the dealership for repairs.
I think Fords biggest stupidty was always wanting to to re-flashes and up-dates,changing things. And everytime they did it ran worse.

More Power
10-02-2008, 09:57
Thanks everyone for the input,now I just need to do something with the gasses IF I end up doing this mod.
Thanks again for the feed back.

I've thought about adding the LB7 crankcase vent system to the 6.5, which, like the LLY+ Duramax also recycles crankcase gases. The inside of the 6.5 intake manifold is always coated with an oil film - just like the LLY+ Duramax.

Jim

D_R_C
10-10-2008, 09:52
I've thought about adding the LB7 crankcase vent system to the 6.5, which, like the LLY+ Duramax also recycles crankcase gases. The inside of the 6.5 intake manifold is always coated with an oil film - just like the LLY+ Duramax.

Jim

I did the PCV re-route on my ex 03 Ford 6.0(I`m sorry for the bad language)after the turbo broke,the vains was caked with oil sludge from excessive blow-by.

Any opinions on this:
The Ford tech feels that the turbo and upper cylinders need the lubrication from the closed system mixing with the fresh air intake.
I know times have changed and the quality, but diesels ran many miles and years with a open system.