6.5 l Diesel engine problem, valves or bearings?
- WolfinJeepsClothing
- CHC Navigator
- Posts: 98
- Joined: Sat Dec 31, 2016 10:44 am
6.5 l Diesel engine problem, valves or bearings?
I just can't seem to get a break. Yesterday was taking out the Humvee for a drive and as i was about to pull on to the DVP something let go. I had heard a slight lifter type ticking just before it got bad, there is a video attached if I can get it to upload.
As near as i can tell it is the driver side valve train but I am not 100% sure. I am debating whether to pull the valve cover off or to take it to a shop for professional repair. I am a bit worried about having to remove all the injector lines just to get the cover off and look. Oil pressure and level, coolant and trans fluids were all good, I had actually just checked them before i left.
I will have to download the video from my iPad in a separate post.
As near as i can tell it is the driver side valve train but I am not 100% sure. I am debating whether to pull the valve cover off or to take it to a shop for professional repair. I am a bit worried about having to remove all the injector lines just to get the cover off and look. Oil pressure and level, coolant and trans fluids were all good, I had actually just checked them before i left.
I will have to download the video from my iPad in a separate post.
My Humvee is special, just like everybody else's.
1987 HMMWV M998
1997 Jeep TJ
2007 Jeep JKU
2005 Jeep ZJ
Previously had 1984, 1987, 1991 XJ, 1994 YJ and some others I prefer not to talk about....
1987 HMMWV M998
1997 Jeep TJ
2007 Jeep JKU
2005 Jeep ZJ
Previously had 1984, 1987, 1991 XJ, 1994 YJ and some others I prefer not to talk about....
- WolfinJeepsClothing
- CHC Navigator
- Posts: 98
- Joined: Sat Dec 31, 2016 10:44 am
Re: 6.5 l Diesel engine problem, valves or bearings?
Videos from inside the doghouse....with a stethoscope it seems to originate from the left side.
You do not have the required permissions to view the files attached to this post.
My Humvee is special, just like everybody else's.
1987 HMMWV M998
1997 Jeep TJ
2007 Jeep JKU
2005 Jeep ZJ
Previously had 1984, 1987, 1991 XJ, 1994 YJ and some others I prefer not to talk about....
1987 HMMWV M998
1997 Jeep TJ
2007 Jeep JKU
2005 Jeep ZJ
Previously had 1984, 1987, 1991 XJ, 1994 YJ and some others I prefer not to talk about....
- GreenMeanie
- CHC Pilot
- Posts: 426
- Joined: Tue Jul 22, 2008 3:28 am
Re: 6.5 l Diesel engine problem, valves or bearings?
Sounds like a rocker trying to push a seized push rod.
Cover and maybe even the head has to come off anyway so you will find out for sure.
You should also do a Blackstone oil test to see what else may be in there.
Only other thing i can think of is a bad injector may have torched a small hole in the piston.
It can sorta sound like that.
Sorry your having all these issues.
Cover and maybe even the head has to come off anyway so you will find out for sure.
You should also do a Blackstone oil test to see what else may be in there.
Only other thing i can think of is a bad injector may have torched a small hole in the piston.
It can sorta sound like that.
Sorry your having all these issues.
Early 1997 HMC4, 1 of 35, Original Block H296, 110,000 miles and no cracks yet, G10 green
Custom made Brush Gaurd, Roof Rack, Overhead Console and Sound System.
Custom made Brush Gaurd, Roof Rack, Overhead Console and Sound System.
- ddgermann
- CHC Pilot
- Posts: 299
- Joined: Sat Jun 15, 2013 11:07 pm
- Location: Edmonton
Re: 6.5 l Diesel engine problem, valves or bearings?
Hi Wolf,
How many Kms on this engine? Is it original or a later year drop in?
How many Kms on this engine? Is it original or a later year drop in?
1999 H1 HMC4 (black on black)
Hummer: from The Century Dictionary and Cyclopedia. n.[font=inherit;font-size:.9em;font-style:inherit;font-weight:inherit] "One who, or that which excels in any quality, especially in general energy or speed."[/font]
Hummer: from The Century Dictionary and Cyclopedia. n.[font=inherit;font-size:.9em;font-style:inherit;font-weight:inherit] "One who, or that which excels in any quality, especially in general energy or speed."[/font]
- GreenMeanie
- CHC Pilot
- Posts: 426
- Joined: Tue Jul 22, 2008 3:28 am
Re: 6.5 l Diesel engine problem, valves or bearings?
Other thing i use is a breaker bar as an earpiece. Better than steth IMO.
Put the open end to your ear and the butt end to the side of each injector and listen.
Put the open end to your ear and the butt end to the side of each injector and listen.
Early 1997 HMC4, 1 of 35, Original Block H296, 110,000 miles and no cracks yet, G10 green
Custom made Brush Gaurd, Roof Rack, Overhead Console and Sound System.
Custom made Brush Gaurd, Roof Rack, Overhead Console and Sound System.
- WolfinJeepsClothing
- CHC Navigator
- Posts: 98
- Joined: Sat Dec 31, 2016 10:44 am
Re: 6.5 l Diesel engine problem, valves or bearings?
The odometer has 30000miles on it, so 50k km. But I had heard that they didn't put in the 6.5s in Humvees until 1989. Which means it's probably been swapped out at some point since it's an 87.
I just found the nameplate today while I was under it. When I first got the Humvee I had to figure out if it was a 6.5 or 6.2.
I just found the nameplate today while I was under it. When I first got the Humvee I had to figure out if it was a 6.5 or 6.2.
You do not have the required permissions to view the files attached to this post.
My Humvee is special, just like everybody else's.
1987 HMMWV M998
1997 Jeep TJ
2007 Jeep JKU
2005 Jeep ZJ
Previously had 1984, 1987, 1991 XJ, 1994 YJ and some others I prefer not to talk about....
1987 HMMWV M998
1997 Jeep TJ
2007 Jeep JKU
2005 Jeep ZJ
Previously had 1984, 1987, 1991 XJ, 1994 YJ and some others I prefer not to talk about....
- Monk
- CHC Trail SuperGuide
- Posts: 1232
- Joined: Mon Oct 01, 2012 10:36 am
- Location: Ontario
Re: 6.5 l Diesel engine problem, valves or bearings?
Serious ? Man what else?
Uggg sorry to hear, so hard to always tell how the previous use was....or maintenance ......
One thing I got to understand is these are not hard per say, (6.2 / 6.5) for repair,... It's mostly hours,.
Man I hope it's something stupid small, like an injector,.,,or tranny protection plate hitting the flywheel,...
But sorta has a rocker ish sound....like one fell,
Jezzz your motor sounds smooth (minus that tick),..,, or your video has sound enhancement to make sound better... Lol I look around when ever I start, lol to see who pissed at the noise, hahahha
But ya before ya "dig" look for easy visible weird stuff first..
Uggg sorry to hear, so hard to always tell how the previous use was....or maintenance ......
One thing I got to understand is these are not hard per say, (6.2 / 6.5) for repair,... It's mostly hours,.
Man I hope it's something stupid small, like an injector,.,,or tranny protection plate hitting the flywheel,...
But sorta has a rocker ish sound....like one fell,
Jezzz your motor sounds smooth (minus that tick),..,, or your video has sound enhancement to make sound better... Lol I look around when ever I start, lol to see who pissed at the noise, hahahha
But ya before ya "dig" look for easy visible weird stuff first..
Last edited by Monk on Sun Apr 16, 2017 9:29 am, edited 1 time in total.
96 HMC4
Optimizer N/A
Super Swamper IROKS 39.5x13.5x 16.5
Optimizer N/A
Super Swamper IROKS 39.5x13.5x 16.5
- WolfinJeepsClothing
- CHC Navigator
- Posts: 98
- Joined: Sat Dec 31, 2016 10:44 am
Re: 6.5 l Diesel engine problem, valves or bearings?
I am a bit frustrated since the engine did purr like a kitten until things started going sideways. Still starts like a champ, but the day before I took the Humvee out and had a white smoke till she got warm a lot worse than I had ever seen (5 minutes till I drove a bit). So I checked the glow plug harnesses since the front connectors were under a lot of tension. After reseating (aka. Jiggling) the connectors on the glow plugs the next start was normal, about 10 seconds of smoking and it quickly cleared up.
Maybe it was just a coincidence and this is related to the issue I have now.
The fluids are still clean, I don't want to drain the oil until I am sure I don't need to move the truck. But there is no sign of oil loss or contamination yet.
If I pull off the injector lines, all four on that side am I going to have trouble bleeding it?
Is there any way this type of noise could be contaminated fuel related, as in water.... I don't think it is but I thought I'd ask?
This is what it sounds like underneath.
Seeing as it seems to be the top end I figured the valve cover first and if that's clear the oil pan to check the bottom end. Neither of these I look forward to doing in the driveway since the hood doesn't keep the water from going in the engine bay...
Maybe it was just a coincidence and this is related to the issue I have now.
The fluids are still clean, I don't want to drain the oil until I am sure I don't need to move the truck. But there is no sign of oil loss or contamination yet.
If I pull off the injector lines, all four on that side am I going to have trouble bleeding it?
Is there any way this type of noise could be contaminated fuel related, as in water.... I don't think it is but I thought I'd ask?
This is what it sounds like underneath.
Seeing as it seems to be the top end I figured the valve cover first and if that's clear the oil pan to check the bottom end. Neither of these I look forward to doing in the driveway since the hood doesn't keep the water from going in the engine bay...
You do not have the required permissions to view the files attached to this post.
My Humvee is special, just like everybody else's.
1987 HMMWV M998
1997 Jeep TJ
2007 Jeep JKU
2005 Jeep ZJ
Previously had 1984, 1987, 1991 XJ, 1994 YJ and some others I prefer not to talk about....
1987 HMMWV M998
1997 Jeep TJ
2007 Jeep JKU
2005 Jeep ZJ
Previously had 1984, 1987, 1991 XJ, 1994 YJ and some others I prefer not to talk about....
- ddgermann
- CHC Pilot
- Posts: 299
- Joined: Sat Jun 15, 2013 11:07 pm
- Location: Edmonton
Re: 6.5 l Diesel engine problem, valves or bearings?
This sounds "tinny" and stops when the engine gets a little shot of fuel and surges slightly. Do you have the casting numbers off the rear of your block? I am having trouble cross referencing the SN for the engine.
Left Rear:
Right Rear:
Left Rear:
Right Rear:
You do not have the required permissions to view the files attached to this post.
1999 H1 HMC4 (black on black)
Hummer: from The Century Dictionary and Cyclopedia. n.[font=inherit;font-size:.9em;font-style:inherit;font-weight:inherit] "One who, or that which excels in any quality, especially in general energy or speed."[/font]
Hummer: from The Century Dictionary and Cyclopedia. n.[font=inherit;font-size:.9em;font-style:inherit;font-weight:inherit] "One who, or that which excels in any quality, especially in general energy or speed."[/font]
- Roy
- CHC Trail SuperGuide
- Posts: 1933
- Joined: Tue Dec 29, 2009 8:21 pm
- Location: Stratford,Ontario
Re: 6.5 l Diesel engine problem, valves or bearings?
motor seems to be a 6.5
things to do/ check...
add a liter of trany oil to the oil --this cleans some oil slug off the push rods/rockers..run for a bit, did it improve
flywheel...cracked center or loose bolts (12)
things to do/ check...
add a liter of trany oil to the oil --this cleans some oil slug off the push rods/rockers..run for a bit, did it improve
flywheel...cracked center or loose bolts (12)
99 Wagon
5.9 Cummins 12 valve mech. Stocking most parts to fix your H1
41.5-13.5 R16.5 Pitbull Rockers,
Auburn lockers front and rear
Full custom underbody protection
3" body lift
4" side rock tubes
12100 rear cv shafts
5.9 Cummins 12 valve mech. Stocking most parts to fix your H1

41.5-13.5 R16.5 Pitbull Rockers,
Auburn lockers front and rear
Full custom underbody protection
3" body lift
4" side rock tubes
12100 rear cv shafts
519-272-1761 
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