Try using a 425 - dangerous drive shafts - mine snapped on an emergency stop leaving only 3 wheels with brakes. That was with a new driveshaft
Try going up hill - with a modest load on board. 60 - 50 - 40 - 30 - 25 mph if you are lucky.
Try a winters day with frost on the steering wheel for the first half hour.
Delightful 6 volt system - Oh how I love those glow worm lamps - Citroen's idea of light pollution prevention ?

Try a 625 and enjoy motoring a little

Just spent the afternoon dismantling the original engine that came with my van. Here's a few pics:
started with this:
Offside barrel very oily:
Can anyone identify this engine from these marks, stamped into both barrels? The stamp says AM111.101A
There is no tag on the engine. Page 7 of this thread shows other serial nos. that are stamped onto the bottom of the engine case. Other than these, there are no identification marks.

The engine was dusty and full of cobwebs and insect cocoons. Needed a really good going over with a wire brush.

The heavy flywheel looked particularly rusty, but 10 mins with the brush and it's looking surprisingly good:


Carburettor is all there, but I have no clue as to whether it works.

??
Its not an M4

Parallel heat exchangers = 435cc.
Alternator pulley sits further away from the fan cowling than on a 602.

However, cylinder bore, is it 68.5mm?

They usually have a rather distinctive flywheel, mind you, with much less metal
near the outer edge and the pcd of the flywheel bolts is smaller than that on
a 602.

ken

It is the same engine as I have in my van , so must be 435 cc, also the same carburettor.
This is my flywheel before cleaning :


I presume it is the original, because the bolts where "sealed"with red paint.

Same as mine, but I can't remember the AM111.101A stamped in the barrels, will look at these later today.

[quote="Geert"]It is the same engine as I have in my van , so must be 435 cc, also the same carburettor.
This is my flywheel before cleaning :


Your flywheel looks more like Ken's description, Geert. Mine's got more metal:

That is what I mean , The engine is the same, the flywheel is different
What Ken says: parallel heatexchangers.435 cc
The grill in front of the fan : I have three bolts, you seem to have four.
Mine is 1974 and yours 1976, maybe an improvement ?
Do you have a red button to start the engine , or does your's start by turning the ignitionkey?

Key ignition, I think! My van came to me in bits, with most stuff sitting in boxes, with numerous spares/duplicates. I have several speedos, for instance. The original is, I think, a brown "Club" style speedo, with the speed in kms. I have a selection of seats, too. None of them match!

The log book for the van says that it has a 602 engine. It also says that the vehicle is yellow!

Smiffy,
was that flywheel mounted on the engine when you collected your 'self assemble
van kit'?
If it wasn't, might be worth checking that it will fit, as those 435 engines I've seen
had a flywheel the same as that shown in Geert's photograph...

ken