Engine noise on morning start ups! HMMWV 6.5 GEP

[Retiredwarhorses]

Awful is correct! yeah I have a 6.5 GEP Optimizer and she is loud!. It sounds like the top of the engine isn't getting any oil. I decided to do some testing of the Cold Advance solenoid (CAS) I unhooked 569a and 569b and placed them together and turned the Humvee to on/run position and then listed for a clicking sound. Sure enough there was a clicking sound. Then I tested the solenoid by use of my ohm meter just to test for continuity and there was. so its not the solenoid. But just to make sure i started the Humvee with the solenoid unhooked and the noise seemed to be a bit quieter than normal, so while the truck was running i then plunged the solenoid back in while it was still running and the noise got real loud (like normal level). So that pretty much tells me that its defiantly working. So at the end of the day I guess it's diesel thing?

the Cold advance solenoid does just that, it advances the timing the timing when cold.
thus a “clackier” motor.
there are several reason the 6.5 is louder, all having to do with the redesign of the heads.
if you think they are loud, try the turbo diesel on cold start up.

 

[shawnshumvee]

That is the wrong number....the one you need is on the right side
The GEP has a date code example : 06 10 J, ....june 10 2002

Got it. the numbers are not to eligible but heres what i can make out. 12- 05 (or 06) 11?



Also in the valley it says 506 made up with all dots. Thinking its a Navistar cast? it should be because AM took over the 6.5 in yearly 2000 an the my engine has a GEP decal on the valve cover. Of course thats just decal at the end of the day.

 

[Retiredwarhorses]

Got it. the numbers are not to eligible but heres what i can make out. 12- 05 (or 06) 11?

View attachment 721984View attachment 721985View attachment 721986

Also in the valley it says 506 made up with all dots. Thinking its a Navistar cast? it should be because AM took over the 6.5 in yearly 2000 an the my engine has a GEP decal on the valve cover. Of course thats just decal at the end of the day.

Dec 5th 2005

 

[Retiredwarhorses]

And no, people aren’t running around in the military slapping GEP decals on valve covers for lack of things to do.
As a matter of fact, that Label is not orderable. Can it be made? Yes....but let’s be real here.

 

[shawnshumvee]

And no, people aren’t running around in the military slapping GEP decals on valve covers for lack of things to do.
As a matter of fact, that Label is not orderable. Can it be made? Yes....but let’s be real here.

Oh I'm real! The value covers could have been swapped, you never know. It's not unheard of military guys cannibalizing parts! I'm just saying its in the realm of possibility but I agree it's highly unlikely. But enough of that, Can you tell me or direct me as to how you came up with this? specially when the last letter can't be made out, not by me at least. Also i did locate the double (back to back) triangles, so that confirms this is a navistar casting. I also Found J28 stamped on the side of the block (driver side).

 

[shawnshumvee]

Dec 5th 2005

also what is the last character? I cant make it out.
thanks

 

[86humv]

H-2001, J-2002, K-2003, L-2004, M-2005, N-2006, P-2007 and so on....

 

[shawnshumvee]

H-2001, J-2002, K-2003, L-2004, M-2005, N-2006, P-2007 and so on....

Yeah I found that AMG decoder system on the internet. I just didn't know how Retiredwarhorses knows the last character its a "M" I can't make it out for the life of me. It looks all messed up to me? I guess Retiredwarhorses has more experience and better eyes then me. Oh well it sound good to me so I'm going to run with it.
But thanks.

 

[shawnshumvee]

the Cold advance solenoid does just that, it advances the timing the timing when cold.
thus a “clackier” motor.
there are several reason the 6.5 is louder, all having to do with the redesign of the heads.
if you think they are loud, try the turbo diesel on cold start up.

Yeah I already came to that conclusion. I could only imagine how the Turbo sounds! It's just a really BAD sound and as far as I'm concerned NO internal combustion engine should make such a noise, but who am I to say.

Thanks for the info