Why will it not start!!!!

Hi,

I never thought I would be asking this question after years of playing with old bangers, but why will my Lotus not start!

I started the engine last weekend after several years layup. New fluids etc and it started and ran surprisingly well. Drove it up and down my drive and started thinking about the MOT. Tried to start it this weekend and the best I get is a few coughs! Plenty of fuel, and getting a spark on all four plugs, which are damp with petrol. Nothing has changed from last week!

I must be missing something. Any suggestions before I give up the will to live!

Cheers,

David

you are getting a spark, but is it at the right time? also have you got a balasted ign and if so check the resistor. pull out the plugs and rub the electrodes with a pencil as the graphite makes a nice sparkle when cranking.

regards
Mark

Plugs wet with petrol…flooded?

Is it turning over properly. If the earth is not sound and the battery not tip top it won’t fire!

Gareth

Hi. Contaminated fuel? Maybe water. If you took out the ignition leads after running it did you mix them up - sorry to suggest it but I’ve managed to twice - which just means I’m a numpty I realise, but the symptoms are the same - coughs and splutters but no running.

Sean.

I’d also suggest possibly crap fuel, or maybe debris in the fuel lines, could stop the carb floats from filling up after initial cough. Note it’s easy to flood the engine when using Webers (Although you don’t say what carbs you have) - Did you empty & refill the tank after its layip ?

Other favourites have to be ignition related - coil; timing.

But it started & ran well a week ago, fresh fluids, plugs wetted with fuel.
I think maybe it’s condensation upsetting your sparks & if the last time you started the engine you didn’t run it up to operating temp. moisture could have collected or relocated itself.
I’d recommend thoroughly cleaning the distributor cap inside & out also the plugs, plug caps & leads.
A solution that I found worked on my cars & bikes that stood outside.
Cheers
John

Hi

Maybe it is running rich, you started it ok and then the plugs fouled as it ran?

Clean the plugs and try again.

My twin Weber car floods very easily, to start I pump the gas twice and crank. If I touch the choke (school boy error) it floods.

Jason

David,

I’d spray some starting fluid into the carbs while an assistant cranks it over. If it doesn’t start, you won’t learn much but if it does, stop spraying the starting fluid and see if it keeps going. If it dies, try it again and this time, keep it going with the starting fluid for 15 seconds and then stop. If it dies again, you’ve got a fuel delivery problem. Good luck.

Hello? David? At least let us know you didn’t give up the will to live.

Hi all,

Thanks for all the comments! Nine is a day is fantastic and I am not ignoring you all! I have not had chance to get back on this site and did not expect so many replies so fast.

In answer to some of the comments:

  1. The car is turning over very well so good earth
  2. Because the engine was running and I have not touched anything, I am assuming the timing is correct.
  3. The car has been sat in a heated garage so I don’t think there should any condensation, but I will check. However, as I was getting a spark it does not seem likely.
  4. Yes, it was running rich as I did not get it out on the road, but I cleaned the plugs (several times!) so should be OK.
  5. It has delorto carbs, which, like webers, are prone to flooding easily. However, cleaning the plugs and leaving for a few hours usually fixes this too
  6. The carbs are full of fuel and the plugs wet, so I guess there is not a fuel delivery problem.
  7. I did drain the fuel and filled with fresh; Petrol only seems to last a few months now before “going off!”
  8. It has electronic ignition and new leads and coil which rules out most traditional electric problems

It does seem to point to a flooding problem, but 5 does seam to rule that out.

Any other suggestions!

Thanks in advance.

David

David,

If we keep coming up with suggested remedies and you keep coming up with reasons or assumptions as to why our remedies don’t apply, then your car will remain in the state that it is even if you continue to ask for more suggestions.

At this point most would advise:
Remove Electronic Ignition & revert to points for the time being - Have you kept the old condensor ?
Confirm which plugs you’re using

Be prepared for lots of process of elimination troubleshooting !

Don’t ASSUME anything… :wink: Best to check it then you will KNOW for certain. :slight_smile:

The keyword here could be ‘new’ - anything that has changed since it last worked properly could be a cause of (or related to) the problem. I speak form experience… :wink: E.g. Possible scenario - fitted new plug leads & disturbed a distributor that wasn’t tightened down properly, thus upsetting the ignition timing…

Another thought: if you’re happy you have fuel & spark at the correct time, the other ‘ingredients’ for an engine to run are air and compression. :bulb:

:arrow_right: Matthew

What about a blockage in the exhaust? Come on admit it, that’s a good suggestion isn’t it? :wink:

Sean.

Try a NEW set of spark plugs. I have experienced on several occasions that heavily flooded plugs don`t work even after drying for weeks.
(A result of the new crap fuel ???)
Regards
Petter

David

I am familiar with Webers having a few but, one of my TC’s has Delorto’s (S3SS), late last year I had a petrol leak below the front carb, found out they have diaphragms! Got 2 new ones form PM, replaced them thinking all was well.

All was not well, I forgot that petrol eats most sealants, I had put a VERY thin layer of Silicone on the face of the diaphragms, put the carbs back on the engine a day later so it would dry. Engine started fine, got to tune it and thought I was ready for spring! Well, the next time I tried to start it, no such luck, really had me baffled!!! Tried all the normal stuff, slept on it a few times. For some reason, no idea why, I took the K&N filters of and when trying to start the engine, I covered two of the trumpets, the engine came to life, ran rough but on all 4 and would rev but slowly?

So, decided to take the front carb off and check to see if I messed up putting in the new diaphragm, well I did, little bits of silicone evident and, I assumed blocking all the accelerator jets, so out they came and got a good cleaning, all back together without ANY kind of sealant, started and ran fine, back to the same outstanding performance from a rebuild done by Vegantune 28 years ago then parked for 27 years or so! Remember to check and clean the ball seat valve in the plate where the diaphragm screws to!

No I am not saying you have silicone blocking your jets, your problem sounds so much like mine, all seems well, spark, battery, was running etc., you very well just may have some dirt in the accelerator jets? I noticed that the Delortos do not squirt fuel into the head, it is more of a dribble?

I have done stupid things in the past, will do stupid things again, it is great the I am still capable of figuring my stupidity out and fixing it!

Good luck and keep us posted!

Im thinking the halls effect in the distributor has gone A F U ----ed

Hi,

Thanks again for all your comments, and to confirm I just drove the car into the garage and did not touch it for a week until attempting to start it again. I will not get chance to look at it again for a little while, but I will go though all you suggestions, in order of complexity, and when it is running again I will post what the problem was. (my favourite is Alasdair’s)

Cheers,

David

Hi, Im’ not sure this will solve the problem but its worth a look!

http://www.youtube.com/watch?v=cY1YndLmbXQ