LML LML CP3 Timed??? [Archive] - Duramax Diesels Forum

PDA

View Full Version : LML LML CP3 Timed???


LBZ
02-05-2014, 06:14 PM
Buddy at Gm just did his first major fuel system warranty repair on an LML which included a new cp3 and said something about them being timed to the cam???
First I heard of this but I haven't been keeping up with the new stuff much.
Any truth to this?

ryan415
02-05-2014, 06:17 PM
I put a motor in a lml at the dealership and just swapped pumps like normal. Never heard of them being timed. Truck ran good so... Lol

02greysixer
02-05-2014, 06:36 PM
They're timed. Both the lml and 6.7 Powerstroke. We were told it was to sync the pump strokes with the injectors firing.

Sent from my SAMSUNG-SGH-I337 using Tapatalk

doug9940
02-05-2014, 06:40 PM
I'm just asking here, but how do you sink a pump with three pistons to the motor with eight injectors? Seems kinda random at best.

duramaxdiesel
02-05-2014, 07:03 PM
I'm curious about this too. First I've heard of it.


Nick

02greysixer
02-05-2014, 07:09 PM
It's not a cp3, it's a cp4. Different style pump than a cp3.

Sent from my SAMSUNG-SGH-I337 using Tapatalk

Chevy1925
02-05-2014, 07:12 PM
It's not a cp3, it's a cp4. Different style pump than a cp3.

Sent from my SAMSUNG-SGH-I337 using Tapatalk


And only 2 pistons

02greysixer
02-05-2014, 07:18 PM
Correct http://img.tapatalk.com/d/14/02/06/yje3ygur.jpg

Sent from my SAMSUNG-SGH-I337 using Tapatalk

02ilduramax
02-05-2014, 07:21 PM
I beleivw the cp4 needs to be timed to the engine where as a cp3 does not

THEFERMANATOR
02-05-2014, 07:24 PM
Cp4.2 i believe is how they list it. 2 pistons instead of 3 now. There is 2 loves instead of 1 now, so each piston is ramped up twice now instead of once. And yes they have to be timed to the cylinders to maintain even pressure so that the pumping coincides with injector opening. there was a big write up on this when the LML was first coming out, and a write up on the timing marks over at DP.

ryan415
02-05-2014, 07:41 PM
Learn something new everyday, although I do feel pretty stupid now :(

RPM Motorsports
02-05-2014, 07:42 PM
Yup, they are timed for reasons like Ferm said.
Here's a short operation video on the newer pump.

http://www.youtube.com/watch?v=t4lMJ4lqRuo&feature=youtube_gdata_player

LBZ
02-05-2014, 07:58 PM
Cool. CP4 I knew. Forgot about that though.
Thanks for the info.


Sent from my iPhone using Tapatalk

TheBac
02-05-2014, 08:13 PM
Well, after hearing about programming injectors, timing a pump doesnt surprise me one bit.

doug9940
02-05-2014, 08:55 PM
Huh....Ok. So, it has a CP4 rather that a CP3, with 2 pistons rather than 3. And the crank has 2 lobes rather than 1. So, now I'm wondering....
1. Can you still run two injection pumps?
2. Does the second pump still have to be timed?
3. How would you time a belt driven pump?

xtremebikr04
02-05-2014, 09:19 PM
Learn something new all the time! I thought there were already dual pump kits out with a cp3 over the cp4.

mike diesel
02-05-2014, 09:25 PM
People must not follow what new products come out...

Dual pump kits have been out for a while now for lml's and 6.7 powerstrokes. Cp3 mounts in the lml just like any other dmax dual pump kit.

Kappa9012
02-05-2014, 09:41 PM
Cat (I know it's different) C9s and smaller that now run common rails time the pumps to the cam for pulsing as mentioned but also for a serious noise reduction.

doug9940
02-05-2014, 10:10 PM
People must not follow what new products come out...

Dual pump kits have been out for a while now for lml's and 6.7 powerstrokes. Cp3 mounts in the lml just like any other dmax dual pump kit.

I follow ALL the new parts that come out for my LLY. LOL. I don't follow the LML's closely and I couldn't care less about anything with a blue oval on it. :rofl:

THEFERMANATOR
02-06-2014, 08:11 AM
An LML had a CP3 added onto it back in 2011 or 2012. Adding a CP3 to a LML has been proven to be quite simple as the LML uses to fuel pressure regs in stock form, and I believe did away with the popoff valve(don't quote me as the LML is quite a bit ahead of anything I have physically worked on).

nar
02-08-2014, 04:25 PM
H&s sells an add on cp3 kit for the lml.

quadracer37
02-11-2014, 09:19 PM
Also why the lml front cover has an inspection plug in the center/top:thumb:
We run cp3's over the factory cp4 all the time. Also running 2 cp3's (cp4 deleted)

bluessmax
02-11-2014, 10:43 PM
Yep... Cp3 over cp4 is the common. Cp3 does not need to be timesd. We just tuned a Lml with a exergy 12mm cp3, very nice setup but required a little tuning to make it "happy".

Things have come a long ways it's just nuts, I think one of the coolest things is controlling the dual pump setup without a controller.... Controllers deff still have their place, but I foresee everyone going without controllers in the near future. Everything just "works".