I have just sourced a complete 650cc engine and gearbox for a really good price.
It is the one without a distributor, so my question is this. I assume there is some sort of electronic ignition unit that replaces the distributor?

I haven't seen the engine yet but from the pictures it looks like a tidy unit. I have spoken to the buyer and it comes with all the additional wiring needed.

I know Chris is a font of knowledge for all things 650. So if he is reading or anyone else in the know, can they give me a brief description on how the ignition side of things work?

Tony

Hi Tony,

For these engines there are two basic setups.

The first is the traditional coil/rotor/cap with an HT lead from the coil to the distributor with distribution to the cylinders via a rotor and twin leads. Switching uses points.

The second is called a wasted spark ignition and I assume that is what you have on your engine. With this one you have a coil with twin HT outputs and a rotorless 'distributor'. Switching still occurs with a points system in the low voltage primary circuit but both spark plugs fire simultaneously with the one firing in the cylinder nearing the top of the exhaust stroke being 'wasted'.

After market units are available to replace both. They range from replacing the points alone with a Hall Effect switch all the way to a completely electronic system. New twin output coils are also available.

I'm a great fan of the newer electronic systems but also completely understand the argument supporting simplicity. My view is jaundiced because of years of dud condensors, burned points and wasted hours setting gaps and static timing.

My current (no pun intended) system is one of the 123ignition rotor based distributors. It was expensive but the engine runs very well and very smoothly. It cold starts, it hot starts and it runs on the correct advance curve every time.

If you wish, I'll post a couple of photos of the units that are available when I get home from work tonight.

Kind regards,
Chris

Chris you are correct (as always) but there is a third option I believe which is what Tony has purchased. In the very late 126's they had electronic ignition controlled by a seperate ecu box. This takes its signal from a sensor which I think is mounted near the timing wheel. You can tell these engines because there isnt even a hole in the case for a distributor. The problem is if you find an engine they normally dont come with all the electronics to get it going
Damian

OK - thanks Damian, I didn't know about that one.

The 126 (Niki 650) that I bought as a parts car was an Australian model built in 1991/2. It had the double output coil so maybe the Polish built export cars didn't use the true electronic ignition. In that case, a replacement crank angle sensor, ECU and twin output coil is available from Mr Fiat in the USA.

The principles of operation are similar. The Hall effect (magnetic) sensor is mounted either internally near the crankshaft or as it seems in this case, externally on the oil slinger cover. The magnet sweeps past the Hall effect sensor when the crankshaft (cover) reaches the angle that coincides with the appropriate piston BTDC point and triggers the ECU. The ECU acts like a set of electronic points breaking the primary, low voltage, side of the coil. From the picture, the coil will then fire both plugs, so this is another example of the 'wasted' spark ignition for 2 cylinder engines. As revs rise, the ECU will electronically adjust the advance angle. Or at least, that's how I think it works.

Quite conveniently, the oil slinger cover will only go on in one configuration on all 500cc & 650cc engines as the bolts are not symmetrically placed around the periphery so the setup should be quite simple.

Let us know how you get on and post a couple of photos, if only for my benefit

Regards,
Chris

( Not so much of a font, more like just a very small bird bath ... )

Tony, if it's the most sophisticated of those systems and you are missing parts for it, don't panic. My guess is that physically, at least, many of the psrts will be similar or the same as those used on the 126 BIS. The ones I owned were completely unreliable with the only saving grace being that they gave a good impersonation of the 500 driving experience. But I never had any problems with ignition to the point that I have only vague memories of the setup. But it sounds like the same arrangement and you do see a lot of BIS engines on Ebay and new BIS bits must be fairly plentiful from Poland, mustn't they?
I gave one away once to a complete stranger...mug!

That's guys as always. Damian is correct that is the engine I have bought.

In the photos the guy posted it showed a lot of wiring draped over the engine and he says all the wiring is there but now I have a better idea of what to look for.

My first intention is to carry out the famous Peter inspired pallet bench test. So prepare for a video.

Tony

I bought a complete new engine that was all in bits. I was looking forward to assembling something that would be almost unique these days, a brand new engine. When I got the crankcase out to start the project I could not help noticing that there was no hole to take the distributor so it was for a later 126P. The rest of the parts included a normal distributor and not the set up referred to here. So if anyone is after a new 126P crankcase I have one going spare.

Is this any help?

http://www.ebay.co.uk/itm/111496788957?_trksid=p2055119.m1438.l2649&ssPageName=STRK:MEBIDX:IT

fiat500 said:

Is this any help?

http://www.ebay.co.uk/itm/111496788957?_trksid=p2055119.m1438.l2649&ssPageName=STRK:MEBIDX:IT

Click to expand...

Yes thanks Peter that is helpful, at least it gives me an idea of what to look for. I wonder what that bit on the right handside of the picture is? Is it some sort of coil?

I pick up the engine and gearbox tomorrow. I am still in two minds whether to put it in my car or not. Or whether to keep the car original? I will see how it runs when I bench test it.

Yes Tony, that is the coil,I think it's what my BIS had and similar to modern lawnmowers! My Cinq had one but it must have had 4 HT sockets.

I think you need to do what I plan to do. Once I have spare engine I will be stripping it down at a leisurely pace this time. Getting every component checked by the machine shop if beyond my means and then having a complete rebuild with everything machined to the next size up.

That way I can feel fairly confident to go anywhere and for a very long time.

Yeah probably a good idea. It will get it running and see what I have got. I will post some pictures tomorrow. From that pictures that I have seen it looks quite clean.

I know you are from the same school of thought as me as far as originality goes. What are you thoughts on putting the bigger engine and gearbox in my car. Would you do it????

Ideally I would always want my original engine and you hear lots of similar situations where fanatics like us say " but I'll be keeping the original so it can always go back"....I bet it never does!
My 79 year old Austin has an age appropriate engine but not the original. The fact that it's a factory reconditioned unit from eons ago is part of its history and I wouldn't change it. I think the previous owner of your car said he had replaced it but with one from an L, so it's still a 499.
I would be wanting to play about and how better to know what the 650 engine and box are like but to stick them in Luigi.
You might then want to strip the 499 engine and get that in top condition.
Go for it; I won't, think any less of you or Luigi.

I had to have a recon engine installed about 20 years ago that was shipped in from Italy, so it's not running with its original lump. So you are probably right in your thought process about it maybe being an L engine. I know that the engine in Luigi has probably only done about 5000 miles max since its recon so is pretty good.

I will get the new one running and see what it's like but as you say it is probably a good idea to give it a good inspection and see what sort of condition it is in. I will have a look tomorrow and make sure there are no sheared bolts on the crankcase and that the sparks plugs are not threaded etc. all the obvious stuff. It certainly won't be going in Luigi looking scruffy as you can imagine.

A good little project to lock me back in my man garage for the winter months.

Hi Tony,

Don't suppose you picked up the 650 from near Brighton on eBay?

Yes on EBay not far from Brighton nearer to Horsham.

Hey, that's cool. I was born in Horsham, my Dad and brother still live there.

Tim

I was going to look at it tomorrow but you beat me to it haha snooze and lose! He's got like a dune buggy thing with another 650 engine and gearbox on it so I might go for that then do an engine swap and sell on the buggy.

I have an engine I removed from a -97 maluch myself including harness and the black boxes. Please advise if you ned P/N's or any other obvious information and I can have a look and/or take pictures. It has the configuration mentioned earlier in this thread wihtout even a mounting hole for any distributor.
Sverre

Yeah he has that buggy up for £275 but he seems quite desperate for cash and offered it to me for £250, so there is room for negotiation. It looks ok and runs and would be easier to transplant into a 500 because it has a distributor. Mostly it seems cosmetic on the buggy engine as it has been painted in weird colours.

The one I bought comes with half a 126 wiring loom and I need to workout what is needed before I bench test it, it seems to be about 5 or 6 wires out of the whole loom for the wasted spark ignition, so will need a bit of modding.

But it looks really clean I don't think has done many miles. Has good compression, spark plugs aren't threaded and all the bolts going into the block are nice and tight, I don't think it has ever been apart. I committed to buying it as soon as I spoke to the guy on the phone as you are never going to find a 650 engine and gearbox that cheap. Even if I don't use it I can get it running and tart it up a bit and sell it on for much more.

Oh and take a peg to stick on your nose as his lock up is on a pig farm and it stinks.

SverreC said:

I have an engine I removed from a -97 maluch myself including harness and the black boxes. Please advise if you ned P/N's or any other obvious information and I can have a look and/or take pictures. It has the configuration mentioned earlier in this thread wihtout even a mounting hole for any distributor.
Sverre

Click to expand...

Thanks Sverre the only diagram I can find is in Polish but it looks straight forward enough. I have been given what looks like all of the wiring for the engine bay on a 126 so need to try and extract the bits of wire I need from it.

If I have any questions I will post them here or PM you.

Tony