Magneto advice - lucas rf4 in vedette engine

[nicclark]

Hi,

I really need some help with my magneto and I am hoping there may be some people who know about them, so here goes...

I have a classic Fairey Faun, just finished restoring her. She was factory fitted with a Morris Vedette MKII engine which has a lucas rf4 magneto.

The engine needed some attention, which it has now received, but I had to take the magneto off. I also needed a new coil for it which I installed, cleaned the mag up and replaced any bits it needed.

With the mag on the engine, there is a spark at all 4 plugs unless I move the advance and retard lever to fully advanced, when the spark stops. That's the first issue. The second is getting the ignition timing right between it and the engine - I have tried engine at power stroke TDC and the magneto just before firing #1 and got very little - some white smoke and a few backfires.

There is no timing documentation with the manual for the engine - and timing is not my best subject! Do I need to move the engine on a little from TDC so it is further into the stroke? Is it best to experiment?

Regards the spark cutting out at full advance, have I set up the internal timing a little wrong?

Everything else is OK and the engine was running last year. Carb is working, valves all ok.

I would really appreciate any advice or help - I just need to get her started to get out on the river!

Thanks!

 

[duncanmack]

Unusual if you are getting a spark at anything but on full advance - more likely everywhere but at full retard. Are you sure that it is at full advance at the mag (never mind what the lever says)? Are you sure that the mag is set up so no. 1 lead is going to No. 1 plug?

Have you seen this? http://www.sky-net.org.uk/kelvin/tech_info/lucas/rf4_manual/

It's a long time since I timed a "flick-start" (Impulse start) mag on an engine, and I recall it is "fun" (not)

But, you have to set the mag up on the engine so that on full advance it is providing the spark to the correct cylinder at the required time before TDC and that info is specific for the Vedette - sorry if I'm teaching my granny....

These guys have a Vedette manual http://www.thamesengines.co.uk/index.html as did member Jcorstorphine on here in 2004 Perhaps a PM to him?

If all else fails try to get it to spark on the correct cylinder about 3/16" before tdc with the mag on full advance. It should go.

 

[rotrax]

If you want to trust the magneto in use it would be prudent to take it for testing at the very least. A specialist may charge for testing and will give you an opinion on its condition.
I would have it overhauled as a matter of course and would remove it and store it in the airing cupboard at home when the boat is out of use.
Magneto's and boats dont go well together!
I would suggest looking at a classic motorcycle/car / mag specialist-likely to be cheaper than a marine one.........................

 

[nicclark]

Thanks for the replies! I'm sorry, I put full advance but meant full retard. I have a manual for the engine which I thought I had read cover to cover, but having sat in the back of the boat, some pages were stuck. One page details a little about setting the timing and magneto. It suggests playing around with the static timing at about 8 degrees BTDC and then setting the mag to fire at nearly full retard. I tried this yesterday and it just about ran by itself, so a little more fiddling today and I hope to have something that works!

The mag has no impulse coupling either, not sure if this makes it harder or easier, but it just fits into a little slot in the timing chain.

The engine was in a terrible state when I got the boat, the coil in the mag had been bypassed with a standard ignition coil so I got a new one and cleaned the whole thing up.

Anyway, here's hoping!

 

[duncanmack]

Andrew Guttman - Priory Magnetos - is a man you might want to talk to. He is a whizz on bike magnetos and his prices are very reasonable. He should be able to check it out.

https://sites.google.com/site/priorymagnetos/home

 

[Jcorstorphine]

Hi we used to have a Vedette in my Dads boat but it was one of these new fangled BMC "Overhead Valve" engines but it did have a Magneto as my Dad did not trust coil ignition and having to rely on a Battery. The magneto was totally different from your RF4 however prior to installing the BMC Vedette, we had an Austin Lifeboat engine with a Lucas impulse magneto but it did not have an advance retard lever.

As Duncan has said, timing an impulse mag could be tricky and my memory of that is a bit distant it being back in 1959 and I was 14 learning that flicking an impulse mag over on your knee could be painful if one of the leads was touching your leg

One of the things we used to do when we could not get the engine to start was to take the mag home and put it in a warm oven (BUT not too hot) about 50 c ish. to dry out the coil.

Other problem we had was that we timed the Lifeboat engine wrong and had No 1 firing when it should have been no 4 and we got smoke and back firing, so with respect I would go back to basics and check your timing as it sounds as if you are 180 degrees out.

I found these people who may have spares

http://www.magneto-ignition.co.uk/page_3010769.html

Let us know how you get on, best of luck.

 

[Jcorstorphine]

Just one other point is that my Austin Lifeboat engine manual has a section on timing and I think that the Austin Lifeboat engine and the Morris Vedette were the same base side valve engine. If you wish I will scan the pages if you PM me your email address. Do not put your address on forum pages as spammers will take it up and bombard you with junk.

 

[nicclark]

It runs! Thanks to the manual from Jcorstorphine, and a little playing around and adjusting for higher octane petrol it started great. Advance and retard works well in that it will start at full retard and then wants to be moved to advance.

The only thing it now does, which I think is the carb, it that it will often die if I open the throttle, or at least struggle for a few seconds before regaining composure and revving fine. If i cover the air intake a bit this effect is reduced. I have the carb at home this evening and have cleaned the main jets and everything else so hopefully it might do the trick.

I'll perhaps post again in a new thread if not. Thanks for all the help so far.

 

[Latestarter1]

Just one other point is that my Austin Lifeboat engine manual has a section on timing and I think that the Austin Lifeboat engine and the Morris Vedette were the same base side valve engine. If you wish I will scan the pages if you PM me your email address. Do not put your address on forum pages as spammers will take it up and bombard you with junk.

Austin Lifeboat engine (Thetis) was Austin Big 7 three bearing motor the Vedette MkII was Morris 8 918 cc engine and gearboxes also entirely different.

Having run a pair of Vedette MkII's in an Osbourne cruiser for many years and started work at Meakes of Marlow who were the Morris and later Newage agents for the area I know my way around the MkII.

#1 The original Lucas magneto was OK to a point however quality and parts availability in the 1960's was an issue then. Normal practice was to retrofit with Lucas distributor and coil ignition which was a far more reliable set up. Kit of conversion parts from Newage cheaper than going to the BMC dealer in Marlow. Wipac did an alternative magneto however this was worse than the Lucas mag!

#2 Does OP have the original gear pipe raw water pump or the later Jabsco conversion? Once again like the Lucas mag the gear pumps were on their way out in the 1960's and the Jabsco works far better, you simply set the bypass cock on the head once and leave it rather than forever fiddling with it and screwing down grease cup on the pump.

I still doubt the OP's original statement the the Morris Vedette MkII was original fitment in Fairey Faun.

Fairey Marine in Maidenhead fitted out the Faun was set up well after the end of Vedette MkII production. I know that Fairey Marine produced kits for home completion, but OHV Vedette would have been current at the time and far nicer (lighter, smoother) engine for this hull.

 

[nicclark]

Thanks for the reply and the info, really interesting.
I had heard before that the lucas mags were not that great, but this one does now seem to be working well. It has a new coil and generates a good spark at the plugs. I think that if and when I need parts I may need to think carefully about what to do as parts are expensive - distributor cap is £90, half speed gear is the same.

The engine now runs and starts beautifully, the only question I have is the bog / stalling when opening the throttle. As I said, if you close the choke a little, it virtually eliminates the issue, but if the mag is retarded, the issue is much worse - my wondering is that perhaps I need to advance the static timing a little bit more? This engine seems to like running slightly more advanced?

It otherwise runs incredibly well.

Re the water pump - I completely take your point! It is a pretty basic bit of kit! However, it does work well and does not leak now I have adjusted it properly. Do you know the kit I need to convert?

I'm not sure is it was original - the engine is a decade older than the boat (1950) and not an obvious choice, the only reason I think it might be is because of the history of this boat where there is some evidence that it was the prototype for a set of 8 boats - 7 of which went to Bermuda as tenders for the yacht club there. Ours is hull 3. It makes for a good story but I really don't know. If not original, there was a lot of modification made to accept the engine!

Thanks,

 

[Latestarter1]

Cleghorn Waring did the Jabsco conversion kits and they were an incredibly popular fitment to Vedettes and Navigators which were in all manner of hire boats, from slipper launches to motor cruisers, every yard had a petrol very few had diesel.

The cold bogging down is a characteristic of the carbuation, one has to accept it until engine is warm, I used to fiddle with the bypass to make engine warm up quicker. Stretching memory bank now but two types of Solex or Zenith carburetor the ally one and the brass version, the brass version was the better.

Earliest Fairey Faun I am aware of is 1957 and Fairey Marine a somewhat pragmatic organisation so always possible that they would fit an old stock engine to a new boat and the Bermuda yacht club story has a ring of truth.....

 

[nicclark]

Thanks for the info, really interesting. I will have a look for a kit for the pump as it is a bit of a pain.

The bogging happens when warm too which is annoying, so I think I am going to try to advance the static timing a bit more as it is much worse when I retard it a bit so by that token may be better if I advance it! I have an ally carb - damn!

I would really like the story to be true, but it is just that at the moment. I found a couple of old posts from a few people about the Fauns built for Bermuda which claimed that they were built with a slightly higher sheer to accommodate the engine weight and Fairey used older engines for ease of servicing and parts abroad. As ours is hull 3, it could have easily been the prototype for these. With the date - I am also just going on what the broker told me, so it may have been a complete guess though the Faun was launched officially at the boat show in 1959.

I think it may have had work done at Meakes at some point as the number is circled in the engine manual with some notes by it. The boat also spent some time in the early 1970s as a hire launch on the Thames - I found a hire license plate wedged behind the transom supports when stripping it out. I know it was called Helonaki in the 80s & 90s, Stardust for a few years after and that it also spent time in Denmark. I am not sure where to turn for any more info though.

Cheers!