Distributer Setting Up Problems

[boggie]

Hi All,

 

Bit of a strange problem we can't get our heads around and we have wasted 3 weekends tying to resolve, so am looking to you knowledgeable chaps to help us out.

 

The car has been completely mechanically rebuilt and rewired and has a reconditioned set of SU carbs. It was running fine but still retained the original ignition so, as a precaution, I bought a new HT copper lead set with caps and a coil from Moss. I also bought an exchange distributer from the Distributer Doctor, complete with condenser, points and non-rivet rotor. I fitted it all and have not been able to get the car started since. Occasionally it coughs but that is it.

 

I decided to check the spark plugs for fouling and found that two of the Moss caps innards came apart when I pulled them off so I suspected this was my problem. Rather than return them to Moss for a replacement set of the same type and quality I phoned the distributer doctor and bought a full set of NGK caps. I fitted these, expecting the engine to start but no joy. So, as the caps and copper HT leads all came from the same source, renowned amongst us for having some stock of dubious quality, I ordered new HT lead and (just in case) a new top of the range coil (again from the distributer doctor) as the quality of his parts are better than Moss. I fitted them all and tried again. Nothing apart from the occasional kick back through the carbs.

 

So, Dad and I went right through everything again, back to basics. I knew the carbs were all right as they had not been touched and I could smell petrol at the exhaust pipe so fuel was getting through. I fitted a spark tester between each HT lead and spark plug and could see I was getting a good spark at each cylinder. The only option left, reinforced by the kick back through the carbs, was that the spark was happening at the wrong time. After all, this had happened to me once before on my Seven and I had the distributer 180 degrees out, IE firing on the exhaust stroke. So I got out the red Triumph service manual and the Haynes and checked everything once more.

 

I got the engine to TDC, making sure it was on the compression stroke (inlet just closed, pointer next to the hole on the crank pulley) and slackened off the distributer clamp. Next, I wound in the micrometer advance to zero degrees and attached a continuity meter across the points so I could accurately know exactly when the points parted. Now, I read the Haynes manual and it says: “Slowly and carefully rotate the distributer body anti-clockwise until, with the heel of the fibre rocker arm on the cam, the points start to open”. At this point my continuity beeper stopped beeping, indicating the points are open. However, when I did this, the rotor arm was not pointing at No1, it is somewhere between 1 and 3. So after much head scratching I decided that Haynes must be wrong (surely not!). The rotor rotates anticlockwise, so surely this would mean that I would have to get the fibre rocker on the other side of the cam and actually rotate the distributer body slowly clockwise to the point where the points just open to then set the micrometre to 4 degrees. So I did this but again found that the rotor was not pointing at No.1 but was still between 1 and 3, albeit at a different point and of course the engine would not fire.

 

It seems that the relationship between the rotor arm and the cam is not correct as when the rocker is on either side of the cam the rotor is not pointing at No1. However they are one single component so cannot be wrong, or can they? Could it be that the distributer is the wrong one OR that the distributer cam/rotor mount is the wrong one for the distributer? OR are we missing something obvious? PLEASE HELP! The car is a post 60,000 TR3a and the distributer I was sold is a DM2. Any help would be VERY gratefully received. We have wasted many hours and pounds trying to sort this problem and it has taken us away from other important work on the restoration.

 

Many thanks,

Ian

[Guest ntc]

What shape is the tip of the rotor?

[boggie]

Hi Neil,

 

It is hard to explain but it looks something like this:

 

Thanks,

Ian

[Guest ntc]

And the dizzy cap from where?

[boggie]

Hi Neil,

 

I have tried two:

 

1. the original Lucas

2. A copy from Moss

 

Cheers,

Ian

[TomMull]

Ian,

It does sound like you still have a timing issue. I'm sure there are better ways to do this but here is my method, a bit crude, but it's worked for me. I’d remove the distributor and check that the slot in the drive is at 55 degrees to a line across the mount holes and the drive center (also aligned with #1 pushrod tube) at TDC on the compression stroke See p. 17 in the factory manual. I determine the compression stroke by putting my finger over the spark plug hole and then observe the mark on the crank pulley. Then fit the distributor and insure that the rotor arm is pointing to #1 pushrod tube after it is fully seated. Then, with the distributor loose and a timing light or a grounded spark plug connected to #1 lead, slowly turn the distributor back and forth (Not much) until it fires. Then tighten the clamp and re-adjust the vernier from that point. If #1 fires at or near TDC and the rest of the leads are in order, it should start and run.

Tom

[Tony Millward]

Hi Ian,

 

I'm assuming that you installed the cam. Is this timed correctly?. The only other possible alternative is that the Dizzy is a tooth out, this would make the rotor appear between 1 and 3 on the firing stroke.

 

Cheers

 

Tony

[whiteone]

I had a similar? problem and found that the timing mark on the crankshaft pulley is 60 degrees out. 6 bolts hold the pulley to the hub so these must be 60 degrees apart. Has the pulley been fitted one hole "out" by a revious owner? - Is this in fact possible? As a temporary fix I simply added a dot of paint 60degrees from the original and the engine now starts and runs o/k when the distributor is timed to this.

[john.r.davies]

Do TR 2/3/3As have a damper pulley on the crank, like TR6s?

Then, the timing marks can move if the outer part looses its grip on the rubber damper.

 

John

[T Robinson]

Check the offset dog on the distributer that aligns is not 180 deg out. If it is, simply remove the dowel, rotate and re-dowel.

 

Tony

[boggie]

Hi All,

 

Thanks for the replies, here are my answers......

 

TOM:

 

We had removed the distributor and check that the slot in the drive is at 55 degrees to a line across the mount holes and the drive center at TDC on the compression stroke, as per the red book. The rotor was also aligned with No1 pushrod tube as suggested but when we then moved the distributer body to a point where the heel of the fibre rocker on the points was on a cam of distributer central shaft, just opening the points, the rotor was pointing between No1 and No3 positions in the cap. IE when the points are just opening to create a spark, the rotor arm is directly between the two contacts so the spark has nowhere to go.

 

TONY:

 

The engine professionally restored and was running fine with the old distributer so the cam timing is fine. I tried moving the distributer a tooth further to get the rotor pointing at No1 HT post in the cap but then the fible rocker on the points is directly between the cams on the shaft, IE on the land inbetween and points closed.

 

WHITEONE:

 

Checked the TDC by removing the spark plug to see where the piston was and that No1 inlet valve had closed as the piston was rising.

 

JOHN.R.DAVIES:

 

No, TR3s (or at least mine) do not have the damped pulley.

 

T.ROBINSON:

 

Can you expand a little more on this please. Excuse my ignorance but I am not sure what you mean.

 

Cheers,

Ian

[Guest ntc]

As Tony said the drive dog is offset ie more half moon on one side than the other check this first and you will have to rotate the oil pump drive to suit .After that pm me with regard to your rotor arm and cap

[jbenajes]

Ian,

 

Aside from the good recommendations of the friends, here are my two-cents:

 

When you are sure that one of the cylinders, for instance #1 is in compression TDC (both valves closed) you only have to turn the distributor to get the points opening (firing timed at TDC), as you have already done. Then, the rotor should point to one of the HT wire plugs terminals. Connect this wire to the cylinder that is at its compression TDC (cyl #1 in this case). Then connect the next HT wire in rotation order (counter-clockwise looking to the distributor) to cyl #3, the next to cyl #4 and the last one to cyl #2. So you should have the correct firing order 1-3-4-2 and the timing at TDC.

 

Do not trust timing marks nor assumed correct distributor dog positions. Go to the basics, which is only the relative position of the distributor to the crankshaft and the correct firing order in these engines. Of course, assuming correct camshaft timing and the proper function of the other parts (I assume that you checked that the distributor cover is not cracked).

 

Hope this helps.

 

Jesus

 

 

[Rhodri]

Have you the correct distributor cap to suit your new distributor? There is no possible way that the rotor can be between the contacts when the points start to open if you are using the correct cap. The only other thing could be a rotor that is for a distributor that revolves the other way, but you have an arrow stamped on yours to verify it, or a 6 cylinder rotor, but yours looks correct.

 

Rod

[Guest ntc]

Have you the correct distributor cap to suit your new distributor? There is no possible way that the rotor can be between the contacts when the points start to open if you are using the correct cap. The only other thing could be a rotor that is for a distributor that revolves the other way, but you have an arrow stamped on yours to verify it, or a 6 cylinder rotor, but yours looks correct.

 

Rod

 

 

Bang on the money Rod

[Don Elliott]

Last autumn when I put my 1958 TR3A into winter storage, I left only about 3 litres of petrol in the tank. My garage is 55 deg. F all winter and it's dry. In the spring of 2010, I had all the symptoms you describe, but I had done nothing to the electrics or to the engine.

 

After 3 weeks of trying almost everything you can think of (you already have), I assumed the petrol was "old" after sitting 5 months. I drained it out the tank (I have a manual drain valve that I installed myself) and I added 10 litres of new petrol. It still wouldn't run more than about 1/10 of a mile before bucking and stalling.

 

I managed to "buck" it and "buck" it back home. Eventually I took the rubber hose off beloww the sediment bowl in front of the fuel pump and fed the air from the nozzle on my air compressor and blew compressed air back towards to fuel tank. I opened the fill cap and could hear the bubbles in the tank. This is essential to let the air get through the pipe and out the tank.

 

After that, the car ran fine. It turns out I had crud etc. in the fuel line between the tank and my "petrol stop-cock".

 

Give this a try. Even if you smell petrol at the exhaust pipe, remove the caps of at least the float bowl for carb #1. If the bowl is empty, fill it manually by pouring some "new" petrol into the float bowls and see what happens when you try to start it.

 

Then consider blowing the dirt etc. backwards into the tank as I did. Or while your tank is empty, remove the fitting at the bottom off the tank and blow the dirt out the open end of the fuel pipe. This will keep the dirt from getting into your tank. It will work even if you don't have an air compressor. Just get a 2 or 3 foot length of hose like the one your just removed below the fuel pump and blow the crud back with your lung-pressure. It will work just as well.

[brydon]

Hi Ian

 

In your original post you refer to the Inlet Valve just closing as the pointer reaches the hole in the pulley, this puzzles me, as surely the inlet valve would close at the bottom of the compression stroke (thus creating compression) as the piston rises in the cylinder.

could I suggest you check if No1 piston is at the top of the cylinder when the timing mark is indicating TDC? (Gently resting a thin screwdriver through the sparkplug hole whilst checking both valves are closed will assist with this task).

 

Kind regards

 

Andrew

[DAVID A BALL]

Hi All,

 

Bit of a strange problem we can't get our heads around and we have wasted 3 weekends tying to resolve, so am looking to you knowledgeable chaps to help us out.

 

The car has been completely mechanically rebuilt and rewired and has a reconditioned set of SU carbs. It was running fine but still retained the original ignition so, as a precaution, I bought a new HT copper lead set with caps and a coil from Moss. I also bought an exchange distributer from the Distributer Doctor, complete with condenser, points and non-rivet rotor. I fitted it all and have not been able to get the car started since. Occasionally it coughs but that is it.

 

I decided to check the spark plugs for fouling and found that two of the Moss caps innards came apart when I pulled them off so I suspected this was my problem. Rather than return them to Moss for a replacement set of the same type and quality I phoned the distributer doctor and bought a full set of NGK caps. I fitted these, expecting the engine to start but no joy. So, as the caps and copper HT leads all came from the same source, renowned amongst us for having some stock of dubious quality, I ordered new HT lead and (just in case) a new top of the range coil (again from the distributer doctor) as the quality of his parts are better than Moss. I fitted them all and tried again. Nothing apart from the occasional kick back through the carbs.

 

So, Dad and I went right through everything again, back to basics. I knew the carbs were all right as they had not been touched and I could smell petrol at the exhaust pipe so fuel was getting through. I fitted a spark tester between each HT lead and spark plug and could see I was getting a good spark at each cylinder. The only option left, reinforced by the kick back through the carbs, was that the spark was happening at the wrong time. After all, this had happened to me once before on my Seven and I had the distributer 180 degrees out, IE firing on the exhaust stroke. So I got out the red Triumph service manual and the Haynes and checked everything once more.

 

I got the engine to TDC, making sure it was on the compression stroke (inlet just closed, pointer next to the hole on the crank pulley) and slackened off the distributer clamp. Next, I wound in the micrometer advance to zero degrees and attached a continuity meter across the points so I could accurately know exactly when the points parted. Now, I read the Haynes manual and it says: “Slowly and carefully rotate the distributer body anti-clockwise until, with the heel of the fibre rocker arm on the cam, the points start to open”. At this point my continuity beeper stopped beeping, indicating the points are open. However, when I did this, the rotor arm was not pointing at No1, it is somewhere between 1 and 3. So after much head scratching I decided that Haynes must be wrong (surely not!). The rotor rotates anticlockwise, so surely this would mean that I would have to get the fibre rocker on the other side of the cam and actually rotate the distributer body slowly clockwise to the point where the points just open to then set the micrometre to 4 degrees. So I did this but again found that the rotor was not pointing at No.1 but was still between 1 and 3, albeit at a different point and of course the engine would not fire.

 

It seems that the relationship between the rotor arm and the cam is not correct as when the rocker is on either side of the cam the rotor is not pointing at No1. However they are one single component so cannot be wrong, or can they? Could it be that the distributer is the wrong one OR that the distributer cam/rotor mount is the wrong one for the distributer? OR are we missing something obvious? PLEASE HELP! The car is a post 60,000 TR3a and the distributer I was sold is a DM2. Any help would be VERY gratefully received. We have wasted many hours and pounds trying to sort this problem and it has taken us away from other important work on the restoration.

 

Many thanks,

Ian