First fire of the rebuild
 

After the disappointment of the water leak yesterday I decide to get the brake lines finished which I did. It was dull but it worked.

The excitement came when I fitted the battery, solenoid and starter motor.

I was working up the front of the car with a jerry rigged ignition system to see if the starter motor would turn the engine over. This was done with a mixture of heavy duty battery cable and domestic 3 core and after a few seconds of the engine turning I could smell burning plastic.

No worries I thought, it must be the 3 core so I disconnected the battery but still couldn't see where the smell was from. I looked up and the garage roof was full of smoke. Looked to see where the smoke was coming from and it was from the brake hose flexi at the back of the car.

There are no pictures of it all glowing and smoking but here is the before and the end result.
https://lh6.googleusercontent.com/-2...2016.46.53.jpg

https://lh4.googleusercontent.com/-z...2018.16.59.jpg

Needless to say I have now fitted a ground earth cable between the chassis and drive train. I then tested it again and had the engine turning over reasonably without the brake line burning.

https://lh6.googleusercontent.com/-S...2018.17.08.jpg

Still not sure the old starter motor will spin fast enough to start but the later version I borrowed had different fixing points so it looks like I am stuck with a starter motor and separate solenoid.

Looks like the current has gone : battery - starter - engine block - gearbox - propshaft - axle - brake flexi - chassis - battery! A better place for your earth strap which will shorten the circuit is direct from the engine block to the earth tab on the chassis near the left hand engine mount.

Just had a look at your chassis pics from 26th feb and the earth tab I mentioned isn't there, beside the front outrigger. Yours looks like an se5 chassis, mine is a 5a. You could earth from the block to one of the bolts which fasten the tube brace to the suspension towers if it is near enough.

Wow, I've never seen that happen before. Well done for exploring the far corners of the 'things that can go unexpectedly wrong' envelope. :shocked:

Mr Towed - exploring the far corners of the 'things that can go unexpectedly wrong' envelope - Just check out my username ;-)

Andy - I am adding a second earth strap from the gear box to the chassis and from the gearbox through to the inside of the bodywork. I am sure the gear box to chassis one is a duplicate of the one I have just fitted but as you say, it makes a shorter short circuit and better safe than burnt alive!

I am now thinking of running a copper earthing bar inside the cabin but under the trimming from by the gear box up to the front bulk head and then behind the dashboard. This should mean all the cabin electrics can easily be earthed to this bar rather than the 'nest of worms' electrics I had before with earth wires running a long way back from everything.

I have seen brake fluid boil before but that way is a first for me!!!!
It was always throttle and choke cables that glowed when an earth cable was omitted or broke away. Any car with a non conducting body type is normally suffers earthing problems with many components.

BE VERY VERY CAREFUL!

Braided brake lines usually have PTFE cores.

When heated to the point it degrades it releases Hydroflouric acid.

That stuff will eat glass and de-calcify bones (given a large enough exposure) aside from giving you really nasty burns that are reluctant to heal!

I've not been a victim myself, but I've seen the results first hand.

Brake lines were empty of fluid at the time if that makes a difference.

WCA - Glad it wasn't worse.

As they said on Hill Street Blues...

Lets be careful out there.

Paul. :)


[Note to self]

Learn more about earthing my Sammio.

[/Note to self]

:wink:

..

I liked the female lawyer...:shocked:

That counts as a very near miss! Another learning experience.

I have seen some composite vehicles 'double wired' back to the fuse/relay box and thought it might have been overkill. I guess the earlier low volume production glass fibre cars were built to a budget that precluded what might seem to be an expensive luxury, hence after a few years of corrosion indicators that flash inconsistently, pop up headlights that don't (or one does one doesn't) misfires....etc

Could send a copper earth cable from front to back (or in a loop around the chassis) and tap into to that as an earth?

Must read up my book on auto electrics...bus bars etc...

Warning
 

Regards MoriniMans post. I worked in the Mercedes Benz Dealer network from the 1980's untill a few years ago, and there was a bulletin issued From Germany warning of many of the components in engines, gearboxes, axles and brake systems but not limmited to them, that once heated over a certain temperature were classified as harmful. If they were melted, certain components of the materials became carcenogenic and once touched with bare skin could be absorbed almost immeadiately. If the skin was damaged it was reported in several cases that amputation of the effected fingers as in this case was required. This is why you are not allowed to trawl through burnt out wrecks in scrap yards any more, and the fire brigade/police have to take special measures when dealing with burnt out vehicles.

Rocker

I don't suppose you remember if Brake flexi pipes were on the list of things leading to amputation do you?

Don't panic Captain Mainwaring. Seriously, as MoriniMan said we must all be careful. I must apologise for scare mongering, actually all I said is correct, but for amputation to be needed you would have to sustain burn damage to the skin tissue. In other words, if a rubber/neoprene style seal, gaslet or other component were to burn and or melt at high temperatures, the chemical compounds in them change, and ONLY then do they become dangerous. As long as you do not touch a component that is still burning or melting which results in skin/tissue damage then you should be fine. The bulletin did stress that fumes should not be inhaled, and parts should only be handled with gloved hands. In your case, you have nothing to concern yourself over, but it has served to remind us all that we are working with all sorts of chemicals and components that require respect and more importantly awareness of the risks involved.

Rocker

Hmmm.. so that burning Airfix model of the Bismarck (and the occasional Bf109 on a long nylon line) that I poked about and burned the odd finger with melted styrene, and the fumes inhaled from the hot needle being used to add realism / open up holes or weld bits of Tiger tank together might have contributed to my complete and utter Sammio madness. Now I know!

Funnily enough I did exactly the same as a kid - I particularly remember melting the moulding runners over a candle and stretching them to make authentic looking radio aeriels for my 1:48 scale panzers, panthers and tigers. Perhaps a childhood spent assembling and modifying Airfix kits is the perfect preparation for building a Sammio in adult life, or kidulthood as it's now known.

Airfix
 

Don't talk about it too much. If we ask for a show of hands as to who burnt their Airfix kits we will exceed our character limit. Think we all did it didn't we, and then thought oh pooh how am I going to explain all those soot smuts floating in the air. Thanks god for open coal fires.

I sold all my model kits to help pay for the Sammio build...

I used to use a combination of Swan Vesta matches and my sisters cotton wool buds and nail varnish removed to stage spectacular crashes with real flames on my Scalextric track. Happy daze.