GM 6.5 turbo diesel problems..
- Thread starter chilliwak
- Start date
REDROVER
Explorer
If u ever wanna change the motor make sure u get P400
It's heavy duty 6.5 ground up different than any 6.5 even size of the block is much bigger
Forged crank and internals, designed for intercooled turbo setup
Can make close to 600lb tq stock
And 300 hp
However AM GENERAL stopped selling those to public, price went up from 5800 to 10 grand overnight
But why do all that if u only need IP get one rebuild and enjoy many more miles.
If ur motor is mechanical turbo I think u could even use DB2 non turbo injection pump , I'll do some research on that
Does the IP on ur truck have optical sensor on it ? If not
U can use older DB2 injection pump and turn up the fuel
It's heavy duty 6.5 ground up different than any 6.5 even size of the block is much bigger
Forged crank and internals, designed for intercooled turbo setup
Can make close to 600lb tq stock
And 300 hp
However AM GENERAL stopped selling those to public, price went up from 5800 to 10 grand overnight
But why do all that if u only need IP get one rebuild and enjoy many more miles.
If ur motor is mechanical turbo I think u could even use DB2 non turbo injection pump , I'll do some research on that
Does the IP on ur truck have optical sensor on it ? If not
U can use older DB2 injection pump and turn up the fuel
arveetek
Adventurer
I've had my 6.5L Tahoe for 10 years this month. I've gone through countless PMD/FSD modules, one optical sensor, and one complete replacement injection pump. Fortunately I had purchased a low-mileage 6.5L truck with a blown cylinder for cheap, and was able to swap that injection pump over when I needed it. It's not too difficult to replace the injection pump on these engines.
If it weren't for the computer-controlled 4L80E, I would ditch the electronic DS4 pump and replace it with the mechanical DB2 pump. However, the transmission, gauges, etc., all rely on the PCM communicating with the pump to make everything work. It can be done, just takes work and money.
I've got 296K miles on my 6.5L as of today with no major hiccups. Just the normal wear and tear items.
I owned 3 previous 6.2L diesel trucks with no issues as well. Good little powerplants.
Casey
If it weren't for the computer-controlled 4L80E, I would ditch the electronic DS4 pump and replace it with the mechanical DB2 pump. However, the transmission, gauges, etc., all rely on the PCM communicating with the pump to make everything work. It can be done, just takes work and money.
I've got 296K miles on my 6.5L as of today with no major hiccups. Just the normal wear and tear items.
I owned 3 previous 6.2L diesel trucks with no issues as well. Good little powerplants.
Casey
superbuickguy
Explorer
yes, in a heartbeat - especially with this one bit of information - all the 3 bolts that run the pump are accessible through the oil-fill on the front of the motor (remove the fill, pull each bolt, pull the mount bolts, pull the lines, pull the pump). It's really a 4 hour job... here's the list.
1) pull the intake
2) pull the fuel lines
3) pull the 3 nuts on the pump
4) remove the oil filler
5) rotate the motor so you can get the bolts (do so by HAND) then pull the 3 bolts
6) the pump falls out and you remove it. Note where the pin is that sets the timing of the pump, align the new pump pin as the old one). put the spacer spring in the new pump....
7) reverse the procedure. Don't worry about the gear - it will stay roughly in place. It also shouldn't be able to jump teeth (not enough room in the housing, but do be gentle).
Book time is 4 hours to do the task - meaning you should be able to get it done in a day.... DON'T BEND THE FUEL LINES, THEY HAVE A LINER THAT CAN BREAK.... be gentle, force nothing, it's really a pretty easy task to do.
come back when you need to start it - there are tricks that don't use starter fluid to get the pump primed without frying the starter.
1) pull the intake
2) pull the fuel lines
3) pull the 3 nuts on the pump
4) remove the oil filler
5) rotate the motor so you can get the bolts (do so by HAND) then pull the 3 bolts
6) the pump falls out and you remove it. Note where the pin is that sets the timing of the pump, align the new pump pin as the old one). put the spacer spring in the new pump....
7) reverse the procedure. Don't worry about the gear - it will stay roughly in place. It also shouldn't be able to jump teeth (not enough room in the housing, but do be gentle).
Book time is 4 hours to do the task - meaning you should be able to get it done in a day.... DON'T BEND THE FUEL LINES, THEY HAVE A LINER THAT CAN BREAK.... be gentle, force nothing, it's really a pretty easy task to do.
come back when you need to start it - there are tricks that don't use starter fluid to get the pump primed without frying the starter.
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arveetek
Adventurer
Yes. Ditto what superbuickguy said. The only thing you'll have to do is find someone with a genuine GM TECH II scanner to set the timing. You can get it started and running, but it won't run its best without setting the timing via the PCM. Funny thing is, you can rotate the pump back and forth (like you would a distributor on a gas engine), but the timing won't change because the PCM compensates for movement. You have to move the pump, and then tell the PCM via the TECH II that you moved the pump in order for the timing to change.
I've also known guys who just put the pump right back where it was via some scribe marks and called it good.
Casey
I've also known guys who just put the pump right back where it was via some scribe marks and called it good.
Casey
PlethoraOfGuns
Adventurer
If you pop the glow plugs out real quick, it makes turning the engine by hand a lot easier because you won't be fighting the compression.
superbuickguy
Explorer
Ummm... unless the glow plugs are bad - leave them in, they're notorious for popping ends (breaking off) off and ruining motors if removed... why they didn't make the hole substantially larger then the glow-end is well-above my pay grade (all the others do too, so it's not just a GM thing)... If you really must remove, pull the injectors and get them pressure tested while they're out.
about timing. I went through timing changes with several motors, and, while it did seem to make some kind of difference, it never was enough to warrant the change. one thing to remember, though, if you move the pump too much, you'll crack a line.
about timing. I went through timing changes with several motors, and, while it did seem to make some kind of difference, it never was enough to warrant the change. one thing to remember, though, if you move the pump too much, you'll crack a line.
toyrunner95
Explorer
is there any smoke from the exhaust? what color.
