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Stuck with my 6.5

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Freedomdiesel7

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Hey guys, I have a 93 6.5, and the motor was built by my dad, he lowered the compression and put aftermarket heads in it and a whole bunch of other stuff. I bought it off him, put a new injector pump, new lift pump and new injectors. The truck barely fires up whether hot or cold and has a slight miss. If you rev it it won’t return to idle, it just dies. The fuel solenoid is hard wired to the ignition and the glow plugs to a button. I am stuck where to go from here, the motor has less than 2000 miles.
 
Welcome

So we need to start with basics.
Post pics of the engine in different angles because we might spot something.
YouTube or other media linked videos help a lot too.

Ds4 electronic ip (injection pump) that has a pmd and electronic throttle pedal
Or db2 mechanical ip that has a rod and cable from throttle pedal to ip?

DO NOT use starting fluid. Ruins glow plugs, can lift a head off the block or worse.

How did you time the ip after installing it?

Has this engine ran since being rebuilt?

Any pictures you have of the engine during assembly? Specifically the timing chain and ip drive gear assemblies.

Have you done a compression check since assembled? Do NOT do a wet test- you will get injured, dry test only.

How did you bleed the injectors?

Do you have a clear hose on the ip fuel return line yet? Any bubbles or contaminants? If not get one on there asap. 1/4” diameter about 5” long. Comes out the front/top of the ip in an upside down U shape.
 
Will L. said:
Welcome

So we need to start with basics.
Post pics of the engine in different angles because we might spot something.
YouTube or other media linked videos help a lot too.

Ds4 electronic ip (injection pump) that has a pmd and electronic throttle pedal
Or db2 mechanical ip that has a rod and cable from throttle pedal to ip?

DO NOT use starting fluid. Ruins glow plugs, can lift a head off the block or worse.

How did you time the ip after installing it?

Has this engine ran since being rebuilt?

Any pictures you have of the engine during assembly? Specifically the timing chain and ip drive gear assemblies.

Have you done a compression check since assembled? Do NOT do a wet test- you will get injured, dry test only.
Click to expand...
To time it I just lined it up with the marks on the case, but I’ve changed it quite a few times to see if I notice any difference and it doesn’t seem to make any difference. I haven’t done a compression test because I’m a little scared of what I may find. It was converted to gear to gear drive for the IP when it was built, and my dad put about 1000 miles on the motor and then it started having this issue and here we are. I don’t have any pictures of it being built unfortunately, but I do know the block was machined at knightens machine shop in abq New Mexico which was a very reputable shop. The heads and the crank were brand new as well as the bearings and pistons obviously. It is a db2, all mechanical. I can get some pictures of it tomorrow for you, but I don’t think there’s anything that you’ll spot because I’ve had quite a few people look at it at this point.
 
I did forget to mention that it smokes white at idle but it’s not water, it’s raw diesel, you can smell it. The smoke does turn black when it is given throttle and goes back to a little white haze once it builds boost. If I can’t get it I’ll probably throw a 12 valve in it eventually lol
 
Where is the DB2 from? Unless from a reputable builder it's suspect.

Injectors tested for proper spray and pop pressure before installed?

Where is the gear drive from? Been documented that a recent batch of timing gears from Leroy had timing marks off that led to poor running as you're describing or totally trashing an engine forcing valves into pistons. I'd really recommend pulling off the timing cover to see where the marks are.

As already stated put the clear line on the IP return, this will determine if you have air intrusion or not. Is the lift pump verified to be running?
 
There is over a dozen guys on this forum regularly who all out perform almost any shop you could take it to. Not braggin, just saying.
I get calls from shops all
Around Nevada, few from Texas and cali who get stuck on the 6.5.

We got you bro.

If your dad can chime in, have him. More info the better.

Now more direct since I was typing while your last post went up:
You should be able to build boost right away- what turbo? Is the waste gate still vacuum or is it mechanical?

The dropped compression is almost always done in order to run a larger turbo. What pistons did he install?
Lack of boost means over fueling. But everything is in question.

The timing gears - are they from Leroy diesel or DSG? We need to know if he degreed the cam or just threw in the gear drive. This is CRITICAL.

Some of the gears have a 4° advance built in. Some of Leroy’s are in question- like a single batch by the sounds of it, but the ones I have seen were all correct, and all had 4° advance including my set I have on the shelf right now for my build.

What heads were installed? There is known problems with brands such as promaxx.

Don’t give up yet. If you do, then plan to sell the parts here because this is the biggest outlet for the 6.5z
 
DieselAmateur said:
Where is the DB2 from? Unless from a reputable builder it's suspect.

Injectors tested for proper spray and pop pressure before installed?

Where is the gear drive from? Been documented that a recent batch of timing gears from Leroy had timing marks off that led to poor running as you're describing or totally trashing an engine forcing valves into pistons. I'd really recommend pulling off the timing cover to see where the marks are.

As already stated put the clear line on the IP return, this will determine if you have air intrusion or not. Is the lift pump verified to be running?
Click to expand...
The injection pump was not bought from a reputable builder come to think of it. It was quite a few years ago so I don’t remember to much.

I did not test the injectors.

The gear drive was from Leroy, so I’m thinking possibly buy a new injection pump and put an original chain and sprocket drive back on it. What’s your thoughts?

How would you check the timing marks? How would I know they are in the right place?
 
Will L. said:
There is over a dozen guys on this forum regularly who all out perform almost any shop you could take it to. Not braggin, just saying.
I get calls from shops all
Around Nevada, few from Texas and cali who get stuck on the 6.5.

We got you bro.

If your dad can chime in, have him. More info the better.

Now more direct since I was typing while your last post went up:
You should be able to build boost right away- what turbo? Is the waste gate still vacuum or is it mechanical?

The dropped compression is almost always done in order to run a larger turbo. What pistons did he install?
Lack of boost means over fueling. But everything is in question.

The timing gears - are they from Leroy diesel or DSG? We need to know if he degreed the cam or just threw in the gear drive. This is CRITICAL.

Some of the gears have a 4° advance built in. Some of Leroy’s are in question- like a single batch by the sounds of it, but the ones I have seen were all correct, and all had 4° advance including my set I have on the shelf right now for my build.

What heads were installed? There is known problems with brands such as promaxx.

Don’t give up yet. If you do, then plan to sell the parts here because this is the biggest outlet for the 6.5z
Click to expand...
its the original turbo with the original waste gate.

he was planning to run more boost, not sure what his plan was to do that. he cant remember what pistons he used.

The timing gears were from leroy. I just asked him about whether he degreed it and he said he followed the instructions to install but he doesnt remember exactly what that was.

he said they were updated heads from a later humvee. he got the heads from a reputable local machine shop.
 
he said he believes the pistons are oversized but they arent what lowered the compression. he said he lowered the compression with 85 6.2 connecting rods
 
You can use a known good timing chain set to align the crank and cam and IP, and then use that to compare the gears. The gears are definitely better so don't give up on them just yet. Best way to install gears though is to have the head off so you can degree the cam and make sure the #1 piston is at TDC. The instructions form Leroy as far as I know don't say anything about degreeing the cam specifically.

THere's a few good builders out there if you want the pump checked out. Above all else don't buy any pump from Pensacola diesel. If you want contact info for a good builder pm me
 
I'm pretty sure my pump came from pensacola diesel if i remember correctly. are they known for selling bad pumps?

he said when he installed the gears he did it with the #1 piston at tdc and he checked that.
 
Ok. We have a starting point.

Do you have a DIESEL compression tester? Way higher pressures than a gasoline engine unit. If not- time to buy. Don’t worry, same gauge gets used on cummins just a different adapter. https://www.harborfreight.com/master-diesel-compression-test-kit-57588.html

To verify the timing- ya need to rip the front of the engine apart to be 100%, but with a compression check it can tell a lot. We save this move for last.

Put the timing mark back to perfectly lined up for now. NEVER try to time it with engine cranking or running. You don’t need any special tools to time a db2 unless you are racing or trying for very peak mpg.
 
Thing about the gears vs chain- you can be off slightly on gears by mistake and not catch it. It would still run but not happy
 
Will L. said:
Ok. We have a starting point.

Do you have a DIESEL compression tester? Way higher pressures than a gasoline engine unit. If not- time to buy. Don’t worry, same gauge gets used on cummins just a different adapter. https://www.harborfreight.com/master-diesel-compression-test-kit-57588.html

To verify the timing- ya need to rip the front of the engine apart to be 100%, but with a compression check it can tell a lot. We save this move for last.

Put the timing mark back to perfectly lined up for now. NEVER try to time it with engine cranking or running. You don’t need any special tools to time a db2 unless you are racing or trying for very peak mpg.
Click to expand...
I do not, I will definitely have to get one. I actually may know a guy with one, he used to work on old 6.2s and now he does duramaxes.

Ill have to put it back to the mark, right now its about 2 dimes width advanced from the mark. and then I'll have to pull that cover off when i get time, it probably wont be until this weekend.
 
Ok, yeah get it lined up.
Are you familiar with the clear tube for the ip return line? This could solve the issue by itself
 
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