6.2 Military engine

[gsimpson]

I am buying a 1986 Humvee 6.2L NA diesel engine, I have been told they built these engines stronger for the military.

Question

#1 Are the heads are compatable with 6.5L Turbo?

#2 Can I use the mechanical pump on my 1995 6.5L turbo engine?

#3 How big can I bore out the 6.2L diesel?

#4 Can the 6.2L be turbocharged?

#5 Will the injection lines mate up to the DB4 pump if I have to use these with the 6.2L heads?

Once again a big Thank you to any who can help me with my dilemma!

[Robyn]

I am buying a 1986 Humvee 6.2L NA diesel engine, I have been told they built these engines stronger for the military.

Question

#1 Are the heads are compatable with 6.5L Turbo?

#2 Can I use the mechanical pump on my 1995 6.5L turbo engine?

#3 How big can I bore out the 6.2L diesel?

#4 Can the 6.2L be turbocharged?

#5 Will the injection lines mate up to the DB4 pump if I have to use these with the 6.2L heads?

Once again a big Thank you to any who can help me with my dilemma!

The heads will fit
The mechanical pump will work
You can turbo the 6.2

The DB4 IS NOT standard IP used on the 6.2/6.5

If you mean the DS4 electronic ???

NO
The lines are not the same... The DS4 uses a different fitting on the IP end than whats used on the DB2

The basic engine is the same from MIL to CIVY
All internal parts are pretty much the same stuff.

The accessories are different to fit the HMMWV application.

Hope this helps

[gsimpson]

Thanks Robyn

So, can I use the 6.5L lines with the 6.2L heads I was told they had different angles where the lines attached to the heads?

[DmaxMaverick]

Thanks Robyn

So, can I use the 6.5L lines with the 6.2L heads I was told they had different angles where the lines attached to the heads?

The HMMWV (and most van) heads are not directly interchangeable with LT heads. The intake bolt angle and injector angles are different. They will fit the block, but the upper LT parts won't bolt on. The MIL and civi short blocks are the same, though.

The MIL-spec injection pump can be used, but the fuel solenoid will need to be swapped out for a 12V. The DB4 IP was a marine/stationary application pump, and not used in LT or HMMWV applications. They are rare and expensive, but I've not seen but very few uses that actually saw an advantage using them.

[gsimpson]

Will the injectors from the 6.2 work on the 6.5 engine?

I was told that the engine I bought was a bring back from the "surge", and that they are not in bad shape been thinking about a straight swap but its a mechanical injector so I am guessing I would have to build a linkage and use a regular gas pedal and cable to achieve that.

How would it affect the computer to do this?

[Tim01]

If you wanted to keep it mechanical you could do that. If I were you I would but a set of head gaskets and swap the 6.5 heads onto the 6.2 if it had different injector angles and just use all of the 6.5td stuff from the shortblock up. Then it would be a direct bolt in deal, plug up and go.

[DmaxMaverick]

Will the injectors from the 6.2 work on the 6.5 engine?

Not likely. Too many variables. The IP, heads, injectors and lines must all be of the same series, application and generation or they won't fit.


I was told that the engine I bought was a bring back from the "surge", and that they are not in bad shape been thinking about a straight swapThis is a marketing point (hogwash) to sell surplus engines. It isn't likely they know where they came from. The military doesn't intentionally replace/remove good engines in working equipment.


but its a mechanical injector so I am guessing I would have to build a linkage and use a regular gas pedal and cable to achieve that.Adapting a MFI injection pump to an EFI engine/chassis is a conversion. It's a lot more than just installing a throttle cable.


How would it affect the computer to do this?The computer won't be happy. You'll have to do a complete conversion to MFI to make the electronics, instrumentation and tranny (if auto) work. A manual tranny is much more simple, but still requires the remainder of the system to be "converted".

[trbankii]

its a mechanical injector so I am guessing I would have to build a linkage and use a regular gas pedal and cable to achieve that.

How would it affect the computer to do this?

Think of the injection pump as the heart of the engine and the computer as the brain. Then you’re saying you’re going to have the brain control everything but the heart…

It’s going to be reading all the signals and trying to adjust the fuel accordingly - but won’t be able to because “another brain” will be controlling that (mechanically).

As DMax says, you’ll have to make everything mechanical or make everything electronic.