Exactly what the topic says. Could one put a 1.6 pump on a 1.5 engine?
Instinctively I'd say yes, but apparently there's something different?
Reason I ask is I'm slowly assembling a 1.5 that's destined for ECO-type operation, with a little rebuilt K03 and hopefully a small-plunger true-ECO pump. Power is not the goal, economy is, and if successful it would probably end up being used to power an old aircooled Beetle we have in the yard. Mmm, real heat in the wintertime, diesel efficiency in a classic body style...
Why a 1.5? Because I have it, that's why. Only thing it's going to cost me is the price of a hone and rering job, since I finally broke it free. Penetrating oil is your friend, say it with me now...
just rebuild the air cooled engine ( cheaper in the long run )
the deisel is not a "bolt in " replacement ... you need motor to bell housing adaptor $$$$ , a cooling system $$$, special rad hoses , A starter that will work with your setup $$$ , and the space inside the bug to get the diesel to fit ,, the fact that the bug will want to wheelie all the time from the extra weight behind the wheels ....
for what you will spend one the special stuff ... use it to rebuild the bug motor ...
And you want real heat either add an aftermarket ceramic heater, or if you are real lucky you may chance upon an old Gene Berg watercooling set up.
just rebuild the air cooled engine ( cheaper in the long run )
the deisel is not a "bolt in " replacement ... you need motor to bell housing adaptor $$$$ , a cooling system $$$, special rad hoses , A starter that will work with your setup $$$ , and the space inside the bug to get the diesel to fit ,, the fact that the bug will want to wheelie all the time from the extra weight behind the wheels ....
for what you will spend one the special stuff ... use it to rebuild the bug motor ... 
I understand that the diesel is not a bolt in fit. I already have a Kennedy 4-cylinder to aircooled adapter plate that I picked up as part of a lot of parts. Since I already have most of the cooling system that the engine was originally attached to, I just need to pay for the radiator lines.
I believe the adapter plate makes provision for the 1.5 starter to work.
And there is only a 50-75 pound difference between the 1.5 and a 2.0 aircooled, if my earlier research is any indication; moving some things to the fore of the vehicle from their typical positions near the back should balance things out. Even just the extra weight of diesel versus gasoline in the tank would help balance that out.
every wonder why the original porches had (2) 60 LB bumperettes on the front bumpers? anything behind the rear lifts the front end and lessens the front traction ( steering )
BTW Kennedy has good stuff :!:
your rad will to be located up front and electric fan cooled ... usually specialty .. flat and wide ... or it will have to be split in 2 halves to be rear mounted and the air exhausted up through them to the outside.
The ECO plunger will assist in reducing emissions, but I very much doubt that it will assist in fuel economy. In fact, I would bet that it would reduce fuel economy over a similarly fueled engine sporting a 9mm plunger.
Why's that? I thought engines were more efficient as they got closer to 100% load, so "undersizing" or closely sizing the engine so it ran around 75-80% load on a regular basis was better than, say, 50% load?