Only half an engine ??

[Andrew Eales]

Hi All,

Finally inbetween children duties, I have managed to get some time in the garage to tend to the (now 12V -ve earth) bradford.

Unfortunately I can only get the engine running on the passenger side cylinder. The drivers side refuses to play.

Is this "Karma" for converting to 12V I ask ???

Can't be fuel for obvious reasons !

The spark plugs are brand new and I have swapped them over with no joy. The HT leads show good continuity but there is no power to the offending cylinder spark plug. I did have to clean the points before I got any life at all, and I cut back the coil HT lead. This resulted in the one cylinder firing up.

Other than changing the rotor arm, cap and points (and hoping for the best) I'm at a bit of a loss with this one.

It has a brand new 12v coil with the +ve hard wired to the battery, and the -ve straight to the distributor. As mentioned this produced no life, until a bit of emery paper was judiciously applied to the points, dis cap, and rotor arm resulting in half an engine....

Anyone else had this problem or can shine any light on the situation ???
Andrew Eales

Posts: 40
Joined: Tue Apr 17, 2007 10:44 am
Location: Tayside Scotland
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[BarryCambs]

Hi Andrew

Could be a valve stuck open if it's been stood for a while?

Edit - somehow I missed the part about it missing a spark one side! I recently replaced various parts from my bodged distributor with part from the very helpful Distributor Doctor. He did warn me he'd recently had problems with reproduction parts, particularly rotor arms shorting through the rivet and distributor caps. He actually sent me a second hand cap (someone have managed to fit a 4 cylinder cap to mine) in preference to a new reproduction one as he'd lost confidence in them, so if you do need to start changing parts, it might pay to speak to him.

Barry

[Keith Clements]

Worth retracing the steps and thinking clearly.
1. Was it working before it was laid up?
2. What have I touched since it was laid up?
3. What is working and what is not?
I often find the mind leads you astray in fault finding and convinces itself that something is or is not true!

In this case you say you have a spark on one side but not the other even after swapping the lead AND plug. This would suggest a faulty cap.
If you have a spark at a plug outside the cylinder there may not be one when it is inside. You can check the direction of the spark and its power with a graphite pencil. (Search JT).

Clearly there are many reasons a cylinder may not fire which have nothing to do with the spark.
Also 'new' does not mean 'working' especially if it is a Champion Plug or Chinese points or rotor arm or wrong type of coil.

I often find it is the battery or its connections (check resistance of ignition circuit with points closed) or old petrol is the problem after lay up. The later is often proved with the application of some Easy Start.

[Andrew Eales]

Thanks Barry, Perhaps I should get in contact with the distributor doctor. Everything on it looks original at the moment (but well aged and well used !)

Hi Keith, thanks for the reply.
1. Yes.
2. Nothing !
3. Well its getting fuel as its dripping out that hole below the carb and pooling on the block. Fuel is probably about 3-4 yrs old. (unleaded which i believe is OK)
Coil must be working as its providing a good spark to one cylinder (its not keen to rev up, but then its only running on one). Spark plugs ok as have swapped them over with same outcome. So tracing it back wards from working, to not working, the blame should surely lie with the points on the RHS cylinder not opening properly and triggering the HT voltage from the coil. But the lobe's on the distributor shaft look identical and i can't believe that they would wear at all, and certainly not at different rates ! So that would put the blame back on the points..

My plan this afternoon is to reset the gap a bit more scientifically than before, and try again. Will report back !

[Andrew Eales]

Success !!!

The points were miles out. I reckon about 2.5 times the correct Gap.
They must have shifted position as I tightened the screws, as they were set correctly after I had cleaned them up, yesterday.

Anyway it fired straight up with little choke required, and proceeded to merrily gas me in the garage. I knew these were supposed to be super reliable and the machine proved the case citing operator error in this case for sure !

It did however highlight a small oil leak coming out the hole in the bottom of the gear box housing. I assume it to be the rear bearing oil seal - So next question...

How easy is it to change ? - should I bother until the leak becomes a bit more serious, (won't be going far in it, just the odd trip out in the summer).

Can it be done with the engine in place ?

best regards and thanks for all the pointers so far..

[David Kemp]

Regards oil leak, it could be from engine seal or spigot shaft. Has the gearbox oil level dropped?
What is your oil pressure? Is it steady at idle?
You can change the seal without pulling the motor, but that is far more work than simply removing the motor. Bradford motors are easy & light to remove , the balance point is the steel generator support.
I would watch the leak, over a period of time, & try to drive the car a bit more. Possibly even try these wonder products that claim they rejuvenate old seals. I have no experience with these wonder products , my late brother had success with some product on his smoky oil leaking Mazda , what it was I don't know.

[Keith Clements]

KC

2. What have I touched since it was laid up?
I often find the mind leads you astray in fault finding and convinces itself that something is or is not true!

AE

2. Nothing !

AE

They must have shifted position as I tightened the screws, as they were set correctly after I had cleaned them up, yesterday.

I rest my case....

[Andrew Eales]

Nice one Keith !