TDI or just TD (intercooler yes or no)

[Ryland]

So it looks like the the engine is from 1990-'95 indirect injection, with that fuel is not injected directly in to the combustion chamber, thus it looks kind of like this:

[ConnClark]

Originally Posted by Roman

Thanks for the information.

So fyi i have a 1.9 Turbo Diesel whitout injection.

All diesels that run on diesel fuel have injection. Its how they work. The fuel gets injected just before the piston hits top dead center. Injecting diesel fuel before this time or mixing it prior to induction into the cylinder produces a phenomenon called nailing which is similar to a knock in a gas car.

[Mario_Marques]

Originally Posted by ConnClark

All diesels that run on diesel fuel have injection. Its how they work. The fuel gets injected just before the piston hits top dead center. Injecting diesel fuel before this time or mixing it prior to induction into the cylinder produces a phenomenon called nailing which is similar to a knock in a gas car.

Right!
The hot compressed air is what ignites the diesel.

http://www.youtube.com/watch?v=LcQcfoanCU0

some engines are capable of multi parcial injection cycles for better fuel economy(burn better) and noise/vibration reduction.
there is also two stroke diesel engines.

[Arragonis]

Originally Posted by Ryland

So it looks like the the engine is from 1990-'95 indirect injection, with that fuel is not injected directly in to the combustion chamber, thus it looks kind of like this:

Hi,

Terminology - TDI in VW speak is Turbo Direct Injection. There is also an SDI engine which has no turbo or intercooler - think Suction Direct Injection...

Photos would help. For background VW has made quite a few Diesel engines from the 1.6 IDI non-turbo in the Golf 1, a 1.6 Turbo IDI non-intercooled GTD model (Mk2 Golf) and then onto the 1.9 IDI turbo and non-turbo models. If it has a self-made intercooler then it could be any engine I suppose, even a self-made turbo conversion of the Mk 1 ? I think Rob's Polo has the 1.9 IDI NA (Naturally Aspirated) unit.

A 1.6 Turbo (75hp) is listed as a possible engine in the T3 Caravelle which I think is the same as the GTD engine - in which case the unit is from the 1980s.

There is little difference in FE between the engines but performance has improved a lot - you can now get a 170hp TDI with the same FE as the original 1.6 Golf 1 but obviously better go.

Another clue may be to find the injection pump which will probably be a rotary type. The make may indicate how suitable the engine is for BioDiesel use although if it is an earlier unit then it is more likely to be usable on chip fat than otherwise without any mods.

The second fuel pump mentioned has me intrigued as there should just be a single one that injects into the cylinders.

BTW the noisiness of a old-school Diesel is the pump and not the diesel fuel exploding or anything like that - it is one of the reasons a modern common-rail high pressure diesel is so much quieter - no rotary pump.

Good luck though, seems an interesting project.

[cujet]

Keep the intercooler. The above is a good example of improved BSFC (brake specific fuel consumption) with the intercooler.

What's not mentioned is that the more dense air charge (of an intercooled diesel) will also allow more fuel and more power before reaching the smoke limit (under high loads) and the resulting drop in efficiency. Put another way, under normal acceleration, a non intercooled diesel is generally at the fuel/air ratio limit (smoke limit) and a part of that fuel is wasted. That's not the case in a properly turbocharged and intercooled diesel.