Hi All & esp. Ken I guess...

Q1 I have aquired a 425cc manifold with dynamo mounting on it, I'm told it is from a very late 425 engine. The inlet throat appears to be the same size as on the 'ordinery' 425 manifold but the mounting flange is bigger & the pcd of studs greater. What carb should this have please?

Q2 In order to mount the existing 28mm carb I've made an adaptor, it is 1 1/4 long. Engine seems to run ok with this but will this cause any changes I need to worry about? i.e. weaker mixture...?

Thank you.

Sounds like you got an Ami 6 manifold. It won't fit on 425 engines.

If your enine runs ok. and picks up rpm quicklky when hitting the trottle it will be ok I guess.. Only question is it running to rich (running very lean it wouldn't pick up nicely and cruising along it would make the car dancing..... push in the back holdin in push in the back holding in and so on)... Running reely rich you would see at your exhaust making gray
exhaust fumes.... Otherwise drive with it and you schould do 50mile to a galon or 20km to a liter whwn cruising along... and take a look at your spark-plugs after 1000km and compare with haynes.. You can tell by the sparkplugs if it runs to lean or to rich...

Thanks guys.
Viking, it is a 425 one - I'm playing musical chairs with engines, took out the 6volt 425, put in an Ami M4 with 12volts, couldn't get it to run right (unknown 2nd hand engine with some endfloat on the crank but big ends ok. reasonable pics40 carb, ground in the valves, seemed happy running on the bench). In the car, wouldn't run under 1/3 throttle, missing, spitting & backfiring all @ same time, glowing lumps coming out of the exhaust, heating up very rapidly. Changed everything I could, made no difference. Only have one manifold & carb for that so couldn't swop test the theory that exhaust was leaking into the inlet... Anyway that's gone under the bench till I can sort it. So, the original 425 engine has gone back in but with this new manifold, (which I'm told is for a very late 425) apart from dynamo mount, the manifold/exhaust pipe joint seems heavier than the old manifold & I can't actually get the cast clamp on it, it's too fat, and the carb flange is different.
Geo - yes it seems to run ok, just going round the block (I put the gearbox out of the AZU in partly to find out what the box was like and partly because the car one had no synchro left) so the gearing is different, I think, which makes comparing the performance difficult. As you say run the milage up and check stuff...

All 425 6 volts has the dynamo mounted directly on the crank shaft. Never seen or heard of manifold mounted dynamo for 425. Ami 6 6 volt yes but not 425!!! Any chance of a photo?

Yes there were 425cc engines with ami style dynamo mounted on top of the manifold. This were 21hp engines in the last azu models from the 70s some of them belgian production.
Geo had one of those i don't know if he has a picture.

AZU 1969 Belgium:

The manifold that Citroenboat has, came from an engine that a freind got as a spare, when he bought his 1970 AZU Belgian post office van. The van had previously been converted to M28, so it was assumed that the spare was it's original engine. This would fit in with what AZL57 is saying.

However Belgium built are AZAM 6. AM is 602 M4 so manifold is AMI not 425 French built.

Sorry 2cv Vicking. It seems you don't know everything. There are several people saying these are 425cc...

These are 425cc engines, they where first used in Dyane. First with 6volt (on crank) and in 1968 with 12 volt as on picture... Over here they are called 18HP engines.. After that they were also used in AZU at least over here (as seen in the picture)...

Azam 6 used the first engine of the Ami 6 (21hp) and in fact also the chassis and axles and sus-cans.... and these where only used in the (LONG) AK350 also with chassis axles and big cans..


Afterwards when the new engines arrived 435/602, the AMI 6 engines where brought to spain and put in cars over there (AKS400) till they were finised..