Oil tap cutout

[shaunstaples]

I said condenser because of the symptoms, similar to problems seen in the past.

I was 16 in the Fizzie (FS1E) revolution, we all had to have that first taste of freedom 1 year early! My sisters friend Denise was lucky enough to get a brand new one, which turned out to be the best one that any of us had. It was because of her inability to thrash the living daylights out of it and a fault that would make it cut out every couple of miles only then to cool down and get a bit further (late for College), the barrel must have ran in perfect with all the short gentle journeys. Back it went to "Charlie Freemans" for repair which turned out to be the condenser.
I wasn't as lucky, Mine was bought as a non runner, a hole in the piston to match my trainers! Happy days

[ChrisTheChippy]

Thanks grolly. I too like shauns idea of a temporary wire. It will take me a while to sort that one out as I'm electrically inept!
I have kind of eliminated the condenser from enquiries as I've tried several different ones finishing up with a new one from club spares. I've also cleaned and improved all the earth's on the bike.
All the bits I've done over the last month mean it's running better than it's ever done since I've had it until it misfires and cuts out . Just feels like the sparks suddenly disappear. That happens suddenly that's why I'm trying to look at other causes but running out of options. It's only a machine at the end of the day and if all the right bits are in the right order then it should go. That's what I keep telling myself anyway . It's been great to discuss it here, fresh brains really help.

[ChrisTheChippy]

Hi shaun my first bike was a c15 . I sprayed it gold god knows why! Ahh to be 17 again .

[ChrisTheChippy]

Well the saga continues. I finally managed to get to the bike after a couple of days. The wife decided that finishing fitting the new kitchen was more important than fettling the bike. I often wonder what goes through the female mind ...
Anyway I digress.
I disconnected the oil tap cutout switch and tried the bike . Absolutely no difference. Engine runs until hot then misfires and cuts out. I've reconnected the switch now as that is eliminated from enquiries.
One thing I did manage to establish is that it's definitely sparks as I took the plugs out immediately after it cut out and no sparks at all on the right hand cylinder. Intermittent spark on the left hand side also very weak.
I think I'm going to take another look at the distributor and cap . In the absence of any other ideas probably best to check what I've already done. I think I noticed previously that advance retard was a little bit loose . Maybe I'm clutching at straws but at a dead end now.

[Groily]

A hairline crack or other weakness causing tracking in the dizzie cap when it's hot is more than possible. Or a dodgy rotor arm. A worn out AR mechanism won't help but shouldn't kill the sparks. The Distributor Doctor down in Wiveliscombe, Somerset, may have the bits if you need to replace any.
This story is reminding me of playing with BMC minis with the dizzie on the front of the engine 50 years ago . . . a bit of wet through the grill, and the cap would track. Rubber glove type covers helped a bit . . . happy days I don't think!

[ChrisTheChippy]

Thanks for the reply grolly. Yes I had thought of the hairline crack situation as I too had it on a car years ago . Just reminds us how far we have moved on .
I noticed that when the engine gets hot the cap also heats up and could possibly be expanding considerably causing too much gap between the cap and rotor arm . They are not in the ideal place behind the cylinder. It looks to be in reasonable condition but could be out of tolerance. At least I know now that this is definitely being caused by the sparks disappearing. At least it gives me some clue.
One problem may be that the distributor is not marked or plated in anyway so might be a problem with correct parts. I'm going to assume it's the standard dizzy fitted to amc twins and go from there.
BTW I've just come back from a week's holiday in Somerset and Wiveliscombe was a couple of miles away. Sods law ! Thanks for the heads up with that.
Regarding the ar mechanism that was just me thinking aloud, knowing I've also got to address that problem. Might come down to a complete overhaul of the distributor.

[g5wqian]

i had similar thing on my ariel nh , it ended up being the lack of vent in the petrol tank cap , formed a vacuum in the tank and would cough and bang and conk out after 7 miles , if you stopped for couple minutes it would then fire up again and do another 7 miles , all sorted out now though with a working vent .

on my old flat tanker i have a senspray carb and remote float bowl like the old amac carbs , the float will stick in the up position , this causes the engine to cough and bang after a bit and conk out , if i tickle the carb every so often whilst im riding along i can keep it going without a problem , you might have a sticking float in your amal carb especially if its and older plastic one due to the alcohol in todays fuel making the float swell a bit and then sticking , you may be able to sand a little off the float , or get new e10 etc proof one from amal carbs [burlen] .

check battery electrolyte level and charge condition , on my ariel leader it would start to misfire after a bit and i found out i had very low electrolyte level in battery and it wasnt charging up , there was enough in the battery to run it for 20mins but after that it missed and then conked out .
i found the alternator was overcharging the battery [ voltage too high ] and boiling the electrolyte , needs a voltage regulator to cure it .
AO services do an Areg 6 and Areg 12 i think for alternators .

check your distributor cap carbon brush in centre to make sure the spring is good and that the brush is sticking out far enough to make proper contact and moves smoothly , you can buy new brushes from greensparkplug company .
springs easy to get hold of from ebay if you measure it up and do bit of searching , dont forget the spring is also part of the contact beteween rotor arm and coil lead .


if you have a manual tap in the oil line you can just leave it open , i have a manual one on my AJS twin and its left open all the time , i never close it except if i need to remove oil pipe for any reason and cant drain tank .

hope you get things sorted .
cheers
ian

[shaunstaples]

A couple of things I would try to prove a fault with the rotor arm / distributor cap is a good wipe/wash with a dewatering spray, just careful not to soak the brush. You could carry a can and try when it happens and see if it improves things?
also run it in the dark you might be able to see it lit up if your lucky?
Can be really frustrating, just got to keep attacking from all angles one thing at time

[ChrisTheChippy]

Thanks Ian and shaun. I have narrowed it down to disappearing sparks. All other potential problems has been checked and eliminated now. I hope!
I have ordered a new distributor cap and rotor arm (Thanks for the tip grolly) .
Just have to wait for that to arrive and I will see what happens.
Bit of play in the distributor shaft and not in the best condition so if this works its going to get rebuilt during the winter.

[ChrisTheChippy]

Hooray sparks have returned and normal service is resumed!!
Thanks to everyone who gave me advice and hints as to what the problem might be. This afternoon I fitted new distributor cap rotor arm and ( another) condensor. I moved the condensor from its position up on the frame next to the coil down onto the distributor plate . I was unaware until I looked at the drawing of the distributor that it should be in that position. Must have been moved onto the frame when the bike was last worked on in the eighties.
I tested both plugs for spark and lo and behold big spark at both plugs . Bike started first kick and ran strongly so I thought I'd brave a ride out. This is where the trouble normally starts when the engine gets hot so I was not overly confident however it ran beautifully so when I passed the point where it normally cuts out I started to relax and enjoy the ride. I went for a good blast around the lanes and no sign of trouble.
This has highlighted that the distributor needs a rebuild as there is play on the distributor shaft which makes the tick over a bit uneven. This is a job that will now wait for winter along with the oil leak . Even though I have cornered the market in condensers at least I can use the bike now . Thanks again .