Hot starting

[Richardtr3a]

My car starts very well when cold. If it is up to 185 on the gauge the hot starting is very hard and the engine seems to catch just as I release the starter button. I have purchased a racing condenser from Swiftune Engineering Ltd that lives outside the distributor.. Has any one fitted one and does it make a difference that my car is positive earth. If I can put it in the wrong way, I am sure that I will.

 

This whole page is such a small font size that I will soon need more glasses.

 

Can anyone help with

1. Hot starting
2. Condenser orientation
3. Unaccountable shrinking web page on my laptop

thank you

[AlanT]

Dont think the capacitors used in distys are polarised.

The capacitance value required is not high enough to need a polarised type.

[Guest]

I'm on an Apple, so I don't know (can't remember) how it's done on a PC: try Ctrl+ to enlarge the page, Ctrl- to make it smaller and Ctrl0 (zero) to go back to the original size.

 

Re the starting: you've ruled out the fact that modern day's fuels are very volatile and are often the cause of bad starting engines when hot? Did you change brands lately?

 

Menno

[Richardtr3a]

Menno thank you.

 

control + has given me the screen that I used to have. Will I need to do that every time?

 

I put Shell v power in on the way home and the starting has been OK. I will fit the condenser tomorrow and next week end we will go for new plugs ,points, rotor arm and an oil change.

 

I really enjoyed the drive home from the paint shop but it was embarrassing when it would not start, without a push, on the forecourt.

 

Thanks for the help

[RogerH]

Hi Richard,

it sounds like not all your battery volts are getting through when the starter is spinning.

If it push starts when hot or as the button is released then something is adrift.

 

Roger

[AlanT]

Its the old problem with the ignition switch. No coil volts in the spring-loaded end-position.

 

Let go and the volts reach the coil while the engine is still spinning.

 

Seems worse when hot because there the switch is heating up a bit.

 

The push-start that worked is the key pointer.

[stuart]

Its the old problem with the ignition switch. No coil volts in the spring-loaded end-position.

 

Let go and the volts reach the coil while the engine is still spinning.

 

Seems worse when hot because there the switch is heating up a bit.

 

The push-start that worked is the key pointer.

Different ignition switch on a 3a. Its just an on off type and the starter is on a push button. Not all TR`s are like a 4a.

Stuart.

[AlanT]

Very modern that!

 

So why does it start when he lets go of the button?

 

Some contact wear problem presumably.

[RogerH]

Hi Al/Richard.

with the ignition switch 'ON' 12volts are going to the coil. Press the starter button and the volts are pulled down (even with a good battery to a degree).

Let go of the button and full volts come back to the coil (only for a moment) and she starts. Obviously the push start does not affect the battery.

 

So it works when cold but not so good when hot. Something doesn;t like heat + the slightly lower battery state (if present).

Capacitors (condensors), coils and connectors (the three C's) (a bit like the three R's - reading, riting, and rugby). Oh and the Ig switch.

 

Check the battery - 12.6V+ with enigne off.

Change the capacitor for a new Martin Jay item. Then the coil. Check all the connectors in the loom from switch to coil ( dizzy). Change the Ig switch.

Do things one at a time so you know what the cause was (for the next time).

 

Who knows this may work!!

 

Roger

[Richardtr3a]

Thanks Roger I will keep working on it.

[littlejim]

Could it be his timing adjustment??

I don't know the answer, but my 4A did strange stuff like that until I got it right.

Edited May 11, 2013 by littlejim

[BlueTR3A-5EKT]

Thanks Roger I will keep working on it.

Is your coil wired the right way round?

Had this on an E type. Ran like a bag of poo when hot and hated hot starting. Reversing the coil leads solved the issues.

 

For + ve earth car the wire to the distributor should be on the + ve coil terminal. Vice versa for - ve earth cars.

If your coil has sw and cb on it you will need to discover which vehicle earth polarity it was made for, it might be stamped somewhere on the coil..

If in doubt substitute the coil for one you know works and can see how to wire up correctly.

 

Cheers

Peter W

PS Of course it might also be the non return valves in your petrol pump......

[Guest ntc]

Baseplate wire in the distributor ?

[ianc]

If the engine is very hot when you park the car, just release the bonnet (no need to lift it fully open) allowing air flow from the ground upwards - this can make quite a difference. Don't forget to secure the bonnet before driving off!

 

A few years ago, Tony Thomson passed me this useful tip on checking whether a coil is connected correctly:

According to Tony Tranter in Haynes "Automobile Electrical Manual", ignition systems are designed to have negative polarity at the centre electrode and if reversed can be up to 40% less efficient.

Coils for both Positive and Negative earth vehicles were produced, but who knows if anyone has changed a coil for the wrong type in the history of older vehicles, so it is wise to check polarity of the spark (see below for testing polarity using a lead pencil).

With early coils, swapping the CB and SW leads will switch polarity of the spark. Later coils use + and - but the requirements are the same.

To test the spark direction with a lead pencil, interpose the writing tip of a lead pencil between the spark plug top stud and the HT lead, leaving a small gap either side of the pencil tip. If the polarity is correct, a flare between the pencil and the spark plug will be seen (if the flare is between the pencil tip and the HT lead, then the polarity is reversed).

 

Ian Cornish

[Richardtr3a]

This is very helpful indeed. I will try the pencil today. My coil has + and - and the car is positive earthed and the + side of the coil is connected to the distributor.

 

I had some trouble with the petrol pump leaking and fitted a new Standard Triumph unit, bought at the IWE, to stop the leaks. This was only last year so the non return valve should be OK?

 

However I was talking to Martin Jay, the distributor doctor, and he told me that he carried out product testing on condensers from four different makers in the far east, on behalf of Moss. They were all deficient in terms of the internal construction. They have orange wires. My condenser has an orange wire and I have now ordered a condenser from DD as a spare. I also plan to fit my Swifttune racing condenser. He also explained that my spare coil, a gold coloured one in a Lucas blue box DLB105, may not be up to standard. There have been problems here as well.

 

Who would go into business where you can not rely on the manufacturer to stick to the original specification. I think we are lucky, in the TR world, to have companies willing to get involved at all.

 

Thanks Richard

[Fireman049]

Hi Richard ~

 

Modern petrol as you know runs hotter. I carried out the following modification to the bonnet of my 3A by 'reverting' back to the original TR2 configuration of four vent. slots.

 

In the words of a certain supermarket "Every little helps!"

 

Regards ~

Tom.

Edited May 12, 2013 by Fireman049

[Richardtr3a]

An update

 

I fitted my uprated condenser and set off for Star 90.The starting seemed better. But I was keen to arrive and did not give a full test. On the way back I stopped and let the under bonnet heat build up a bit and the starting was instant. I tested it many times on the way home today and the starting is now very reliable. The racing condenser was £25.00 but was well worth it.

 

I was also trying to get better miles to the gallon, by cruising at a rather dull 50 mph. The last test that I calculated showed only 23 mpg. I have just completed the round trip of 385 miles for the Star week end. I bought 50.57 litres of fuel, mostly Shell, and this gives me 34.65mpg. Can this be connected to the new condenser? I was discussing cold starting with another TR3a owner at the show and he uses the choke. I explained that I must be running rich because I did not need the choke this year. However this morning I did need the choke for the first start of the day.

Is the car tuning itself as a reward for the fancy condenser which is making it feel proud?

[RogerH]

Hi Richard,

do another of your 'long runs' and pull over to check the plug colour.

However before you stop cut the engine and glide to a halt (this should keep your plugs at the same colour as when cruising).

What colour are the plugs.

 

Your new capacitor (condensor) should not affect the mixture but may be it is allowing for a more complete burn. This 'more complete burn' will also give you more MPG.

 

£25 for the capacitor - is it owned by a syndicate.

 

Roger

[hpremote]

Hope this isn't too much of a thread hi-jack. I spent a couple of hours on Sunday failing to start the 3; it had been running great when I put it away a couple of days before, so I thought the damp of a couple of days' deluge was the cause. After having pulled, cleaned and re-gapped the plugs and tested the high and low tension circuits, I discovered the coil HT lead was arcing through the rotor arm. So I rootled through the spares boxes and uncovered two rotor arms, one of which looked unused. Fitted that one and the engine roared into life. Took the car for a 25 mls test run and on the way back into the suburbs, the engine began misfiring and died completely; fortunately my momentum carried me into a pub carpark where the bonnet could be raised. A small, interested crowd came out to watch...

Blow me down - another failed rotor arm... fortunately I'd thrown the second spare one into the glovebox and that, when substituted, got the engine going.

Yesterday, first thing therefore, I was on the blower to Martin - aka the Distributor Doctor - and ordered one of his red rotor arms (they're now additionally stamped 'DD' to avoid cheapo copying). He also talked me into getting one of his magic condensors, too. Total bill incl. VAT and package, came to £19 - and the bits arrived in the post this morning. Great service from the DD.

Tim.

[Richardtr3a]

I am fitting the red rotor from DD this afternoon. But I am trying one step at a time. Let me know how you are getting on.

 

Thanks

[Norman D]

Is your engine to chassis earth braid corroded or missing? Does your choke cable get hot when spinning engine on starter?

[Richardtr3a]

My earth strap is new. That is how I see it in my memory, because when I fitted the new engine I fitted two, one on each front mounting. However the engine has been there over ten years so it must be time to clean them up and make sure.

There was a TR3 at Gaydon on Sunday who had an extra strap from the distributor mounting bolt to the body mounting bracket on the chassis opposite the distributor. I think that must be a useful modification I will try in the summer.

I am pleased so far and will now address the rear brake problem while things are going so well. Maybe this is a lucky year.

thanks

[RogerH]

Hi Richard,

regarding your 'extra' earthing strap; I also have a third strap that goes from the battery Neg to the engine block attached at the coil attachment bolt.

I had a nagging thought that as the body isn't necessarily attached to the chassis (electrically) then that could be an area of problem.

So by having the chassis/block, battery/body and battery/block connected then everything is guaranteed to be connected (maybe).

 

Roger

[Guest]

There was a TR3 at Gaydon on Sunday who had an extra strap from the distributor mounting bolt to the body mounting bracket on the chassis opposite the distributor. I think that must be a useful modification I will try in the summer.

I am pleased so far and will now address the rear brake problem while things are going so well. Maybe this is a lucky year.

 

 

regarding your 'extra' earthing strap; I also have a third strap that goes from the battery Neg to the engine block attached at the coil attachment bolt.

I had a nagging thought that as the body isn't necessarily attached to the chassis (electrically) then that could be an area of problem.

So by having the chassis/block, battery/body and battery/block connected then everything is guaranteed to be connected (maybe).

 

 

Good idea. My Saab 96 has an earth strap routed like this. Funny thing is, the Saab 96's electrics are a mix and match of Lucas, Hella & Bosch parts. But one thing is for sure: these old Saabs never have starting problems.

 

And perhaps there's one more thing to consider: the position of the coil. I mounted mine away from the engine on the LH inner wing. Some coils tend to brake up due to heat and vibration. In that case, the engine's side is not the best place to be!

 

Menno

 

Edited May 23, 2013 by Menno van Rij 2

[Richardtr3a]

An update on this problem.

 

I fitted this Swiftune racing condenser made for minis and the starting was 95% better, I then fitted points and rotor from Martin Jay and now it will start from hot in traffic or parked up, on the first turn of the starter. I am going to add an earth from the coil bracket to the chassis mounting nearby as well.

 

The condenser was the problem. I understand that some new ones only have 1.0m of foil against 3.0m required. How can this be a saving for the supplier?

 

I can stand next to the car and press the starter and it fires immediately. Best it has ever been while in my ownership. Thanks for all the advice.