Are you lifting the pins fully ? That is a very common mistake. If you are that is way too much, they should only be lifted 1/32" (0.8mm) to gain the mixture check.

Check the plug colour too, I really can't believe it's too weak, too rich would cause hot start problems, and it would also run fine when it is running.

You could set it to 3 - 4% CO and try it again, or use a vac gauge as Clyde said.

 

Hi,

I'm only lifting them slightly and the engine slows down, the plugs are a nice grey/beige colour.

When I have the hot starting problem its not even trying to fire.

I have ordered an electronic ignition kit for it as I wanted to fit one anyway and it seemed like a good time. Probably won't make any difference but i'm still running the original points and condensor as I've had a load of trouble in the past with modern replacements.

 

The plugs are saying it's ok, maybe the coil is getting weak, the spark maybe weaker as the coil warms up and unless everything is perfect that may be causing the hot start problem.

Usually the coils will cause a misfire when hot, but it is possible that a weak spark is the issue. Obviously I assume you will be fitting a new coil, just check the impedance matches the electronic ignition you purchase, but if you have a full kit that will be covered.

 

I would fit a known working coil first and get running properly before going with a cheesy after market electronic ignition.
Coils can be very unpredictable, case in point with a RR.

Car ran great and started well from cold, and then you would go into the house from a fully warmed engine, come out and the car refused to fire.
Then it would fire, and then it wouldn't.

Replacing the coil solved this intermittent behavior.

 

I've bought a new coil, electronic ignition, cap and rotor arm. The leads and plugs are new and as its a start/not start problem its unlikely to be an individual lead or plug as it would still start and run (or at least try to fire) on five cylinders.

Thanks for all the replies guys.

 

What kit did you get ?
I had a Luminition kit on my Bentley and one day it just stopped working, had to call a tow truck.
Had a Pertronix kit on my TR7 and it just stopped one day too, the car was running fine and the it ran on 3 cylinders, then 2 and finally just 1, in a time span of a seconds.
It had spark, but refused to run.

 

Its an accuspark kit, will be keeping the points and condenser in the glove box just in case!

 

Would love to see some recent pics!

 

Hi all,

Have been sorting out a few teething problems with the car but its generally going well.

Have had a leak from the brake light switch which has required replacement which was bit annoying as I kept tightening trying to stop it and when removed you can see the fluid running out round the electrical contacts.

Planning to get some good pictures of it this weekend if the nice weather holds up.

I've had a bit of luck when researching the history of it, a very kind lady at the JDHT has arranged for someone there to review the experimental department records and has sent me some copies of pages which indicate that contrary to my previous understanding that the car was registered in feb 1960 and then sold, the factory actually kept it until 1961 and used it for what appears to be engine testing/development work.

Unfortunately the records end in 1961 with a final entry and there isn't any more information about what they did with the car and how it found its way into private hands.

In the records it mentions that at one point it had some engine parts fitted from Mr Bailys car TKV636 and also from TVC420.

I understand believe TVC420 was the original MK2 prototype but haven't been able to find anything relating to TKV636

 

Looking forward to some pics

 

I didn't manage to get any good photos of it but took a few in the garden late this afternoon when I got back.

 

Very very nice

 

Wow, You must be seriously chuffed with that, I would be! And to think it could have ended up being banger raced, Excellent job.

 

Thanks all for nice comments.

I have a few teething problems with it, one was its failure to hot start which I have cured with a new coil, electronic ignition etc. another was a leaking brake lights switch (new part) which I have cut open to have a look inside and put to one side to put photos on here (but can't find now!).

I also have an occasional problem that if you pull away from a standstill really quickly the car goes like the proverbial scolded cat but then when you lift off and reapply throttle it bogs down and misfires for a bit, I'm not sure if its fuel starvation of if the distributor is lazy (the retard sticking a bit).

One other thing is that it still has the original manual steering box which I understand is low ratio,although turning the steering wheel results in direct action at the road wheel when you look at it from outside the car seems very vague in the straight ahead position with a good 1/4 turn either way from central before it seems to do anything.

I had a 1966 S-Type with an XJ6 pas rack and it didn't have this problem so I'm not sure if its just how these low ratio boxes are, whether its the tyres or whether there is a fault somewhere. All the bushes, steering arms and the rubber coupling on the column are new.

I do still have the original manual steering box off the 1966 S-Type (I think) which I assume would fit and might have higher ratio and hence might feel better but then I would need to be a body builder to park the thing!

I don't really want to alter the car too much from standard so PAS would be a last resort but its the only thing I find that I don't like about it.

How does everyone else find theirs if they have a manual steering box? What tyre pressures do people run? I set mine at either 30 or 32PSI and they are 185/15 tyres.

Another problem is that the radio doesn't work, its an old Radiomobile valve unit (R50T) and it worked on the bench but not in the car is just hisses like it has no reception, I've checked the aerial is plugged in (this is the same aerial I tested it with) and its all connected. I would like a radio for times when the sound of the XK is not enough.

I've taken a few more pictures today in better light (and a slightly better location).

 

The leaking brake switch is not uncommon, there are some about that are not made well and the seals leak.

The bogging down sounds to me like there's too much fuel when you reapply the throttle, if the centrifugal advance is sticking you should get pre-ignition and knocking which is not good. How long after you take your foot off the gas do you re-apply, and what difference does it make if you shorten or lengthen this time ?

Re Steering, have you checked all the linkages, if you get someone to wiggle the steering back and forth, you should be able to see if the play is in the box itself or the linkages to the tie rods.

Car looking fantastic

 

Hi Tilleyjon,

When its bogging down it doesn't knock so it may be fuel, I tend to lift off and then put my foot back on a little bit once upto speed to give the gearbox a chance to drop into top. I'm not driving it like this all the time (or very often) but its just a strange why it does this, if its too much fuel what might cause this? When I pull up at the next junction and pull off again its fine.

All the steering linkages are new and there isn't any play in them, they were checked when the MOT was done and I had a look at them over the pit myself as it felt a bit odd driving it down to the MOT. When you turn the wheel in the car it moves the road wheel immediately, its not like there is a delay (which I once had on a VW Type 2). It may just be that the low ratio makes it feel like you have to turn it a long way before it does anything, would the 1966 S-Type manual steering box be the same ratio or a lower one? I never used that one on the car so don't know what it should drive like.

 

There were 2 steering boxes fitted to the Mk2 and S type, the high ratio box (17.6 : 1) part no C8927 was special order, the (20.3 : 1) was standard part No C14845 but the Mk2 and S Type had the same steering boxes. (LHD cars had different part numbers, C14846 and C8928).

The tyre pressures sound ok, but you could try increasing to say 36 PSI and see if that makes a difference, if there is an immediate reaction to steering wheel movement then it is either simply the ratio, or the tyres. The tyres would have to be pretty soft to feel like that though.

If the dampers in the carbs are not falling quickly enough then it may cause this, make sure the vents in the either the damper caps or the chambers are clear, it looks like you have non vented caps, but I can't be sure from the pics, so check the chamber vents are clear.

 

I doubt it is the same thing, but the old radio in mine did something similar. After I had the car switched to negative earth all the radio would do was hiss. The workshop claimed they had switched the polarity on the radio (and had charge me an hours labor for doing so) I decided to have a look and in about ten minutes or so had the radio out, opened up, flipped the polarity, put it back in, and it then worked again. Odd. Probably not what your problem is but you never know!

 

Thanks for the response, sadly the radio isn't convertible to negative earth. I have been told by a specialist that I contacted that the internal connections are all made to the chassis and the complexity of completely reconfiguring all the internals of the radio to work the other way around makes it just not feasible.

 

Are the ratios the same in the steering boxes between early and later cars? If so the 1966 later steering box I have is probably the same and not worth swapping over.

I will try a bit more air in the tyres and see how that feels but I suspect its just how the steering is, it feels a little disconnected but compared to modern cars I drive I suppose this is to be expected.

With the carb chamber vent, is this the diagonal piece in the dashpot on the attached picture?