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Alec Grimsey

S1 Esprit Starting Problems when hot

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Hi all,

 

I would be very grateful if anyone could offer their advice or views on the starting of my S1 Esprit when hot.

 

I know there are lots of discussions about starting but none of them seem to cover my probblem so any thoughts you can offer would be fantastic

 

The problem I have is that when cold, use the choke, don't touch the throttle, turn the key and she fires up straight away. No problem at all.

 

Run the car so she is hot, and turn off. When you go to re-start it is just as if the battery is flat with hardly enough energy to turn the engine and she won't start. I know the battery is new and even if you try to jump it she doesn't want to know.

 

Let her cool down and the battery turns her over a treat and up she fires.

 

I had all the carbs set and re-jetted by S&J Sportscars earlier in the year so don't want to touch these and assume they are set right.

 

I have heard lots of stories about a build up of petrol vapour in the air box giving this problem or due to the engine cover etc, evaporation of fuel in the carbs.

 

I need to sort it somehow as I can't take it for an MOT as I can start and drive there no problem but then can't start it when I arrive unless I wait for it to cool down.

 

Quite a problem, has anyone else had a similar issue or can suggest a solution.

 

Thanks for your help.

 

Alec

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Yes, I'm sure its the vapour build up in the air box.

Others have fitted a purge pump that simply sucks the vapours out of the air box.

You could try removing the airbox and fitting filter socks over the trumpets and see how it goes.

Rob

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If it is a case that the engine is not turning over fast enough to start then it suggests a tired starter or electrical connections needing to be improved. Try using a jump lead as additional earth from block to chassis and see if that helps

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Hello Alec

 

I had the same thing once with my Esprit once I'd got it to the MOT testing station. It started fine in my garage and yet when it was hot at the MOT it wouldn't turn over. We managed to start it with a jump start box and so I cleaned off the main earth strap where it meets the chassis and wiped it with Copperslip. It didn't cause any more problems.

 

My Elite had hot start or hot running issues but they were cured with the fitment of a modern electronic ignition module which I also fitted to the Esprit and they both run well now.

 

Good luck!

 

Simon

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Check the centrifugal advance/retard mechanism in the distributor. If the springs get "tired" then the settings won't return to their retarded "starting position" and the engine will fire too early....before top dead centre...giving exactly the "won't turn over" symptoms that you have, as the starter is trying to turn the engine over against the impulse of the mixture firing! I had exactly this problem on a Bertone Alfa GTV and it took LOADS of finding...but the cure was simply to tweak the centrifugal mechanism. On my case, I found that the springs were actually loose and the rotor arm would wabble about with no defined position when the engine was stopped...it should be held by the springs and not be free to rotate a bit.

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Thanks everyone, I am sure you are all correct to a point, it's now much better but not perfect. Let me explain.

 

I have had the starter motor re-wound and re-furbished by Robson and Francis and this definately helped, but I don't think the starter was that bad before.  I also added an extra earth lead from the engine block to the Chassis and made sure the cables earthing on the chassis had a good contact and were free from paint etc.

The outcome is that when cold, the car starts lovely first time.  When you switch the car off hot and then try to start it straight away again its starts a treat.  But if you run it until hot, switch it off and leave it for about 10 minutes then you seem to have problems. Not sure how to get over this at the moment, I will have to keep working on a solution for this.

 

Thanks again everyone, great input.

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Hi Alec, a troublesome fault.

Question - when did the fault start? I couldn't tell from your first post. Was it before you had the carbs jetted and set?

Just speaking from my own experience, but faults on my own car more often or not have come from disturbing a system in the first place.

Iain

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Is the engine physically turning over slower when hot, or does it spin at the same speed but just not fire? I.e is it starter or ignition related?

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Hi guys,

 

Not sure when the problem started as when I got the car 24 years ago it wasn't running.  I have re-built the engine and it spins freely by hand fine.  It started but was very rich and it was very apparant that the carbs needed setting up.  It went to S&J who set all the carbs up and it started from cold fine and ticked over lovely.  It was then that I noticed the problem as I would let it run until hot making sure the fans etc would cut in, but then couldn't start it again until it cooled down.

 

It is possible that the engine is a bit tight when hot, but I don't really think it is the case.  It turns over fine when cold and when hot, it only seems this inbetween time that it is just as if the battery is flat.  It is possible that it is some kind of vapour lock in the air box / fuel system as sometimes when it fails to turn over properly when you squeeze the throttle it suddenly turnes over fine and starts up. So I am pretty sure its not ignition related.

 

I will keep monitoring it and post on here if I find any solutions or anything changes.

 

Thanks for your help.

 

Alec

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If the engine is reluctant to turn over, this can only be because a) you have a defective starter motor, b) the electrical connections to the starter are bad, c) there is some physical restriction stoping the motor rotating freely or d) it's my distributor problem, causing the engine to fire on the compression stroke. It is barely possible that the carbs are flooding the engine giving a hydraulic lock...but this is hugely unlikely. My bet is still on the distributor centrifugal advance mechanism!

However, if the starter is spinning the engine freely, then it may be down to whatever you are doing whilst you are attempting to start. Manipulation of the throttle can be the key...I fine that my engine starts best when hot by allowing the starter to crank and then slowly and steadily opening the throttle to about 1/4 ...then the engine fires up OK. If the engine doesn't fire, and the ignition and timing are OK, it can be because there is either no fuel, or too much fuel. If the engine is flooded, too much fuel, then the cure is to open the throttle fully as the engine cranks...this will intially squirt more fuel in as the accelerator pumps work, then allow much more air in to dry out the cylinders...once they reach the right mixture, then engine will fire and you have to be ready to close the throttles at this point!! If there is not enough fuel, blipping the throttle will squirt more fuel in...but this can flood the engine and make matters worse! It all comes down to experience and feel, and you can't teach that...just explain what might be happening and from there, you're on your own!!

 

Let's hope you can get it sorted swiftly....

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Do you still have the original airbox installed or are you using the pancake or sock filters? I have always had hot start issues with both the pancake and sock style filters.  The engine will be tough to start and run like complete crap, flat spotting and hesitating until I can get some speed up and get cooler air circulating back there and cooler fuel into the carbs. When I went back to the stock airbox my hot start issues reduced dramatically.  You'll never going to be able to illuminate them 100% due to the enclosed design of the engine compartment.The temperature of the fuel is a factor but it appears more so is the temperature of the air being drawn into the intake.  On the Federal S1 the air is drawn into the airbox via a plenum which is mounted low down in the engine compartment and sucks air in at minimum ground clearance level. If you have the airbox on then disregard what I just said but if not, reinstall it and see if there is a difference.  Or if you no-longer have the airbox and are using pancake filters try mounting a small fan back there triggered by an ambient air temperature sensor.  I considered this but opted to go back to the original airbox. 

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Thanks Gavin, I have the original Airbox and the air is drawn in from an air duct low down  facing towards the front of the car.

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The only hot start issues I've experienced is the engine not firing when it's cranked and the hot air/hot fuel issue as mentioned before. I've never had the engine slow crank like it has a flat battery. Was the problem there before SJ did the carb tune?. The mention that a little bit of throttle can resolve the issue leads to the carbs. But I can't see a vapor lock causing the engine to turn over slowly. Sounds silly I know, but have you checked that the movement of the throttle cable isn't interfering with anything. On my car, the cable goes under the airbox up to the carbs and does run pretty close to the connectors on the starter.

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Thanks Gavin, yes the cable is free.  I am unsure if the problem was there before S&J set up the carbs as it was just generally really difficult to start.  It has only just passed its MOT since I bought it as I have never had iot on the road, so I think over the next few weeks and months I will get to understand its starting characteristics better and hopefully a little bit of throttle will solve things.  I will keep you posted.

 

Thanks for all your help and advice, it really is appreciated.

 

Alec

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I understood these cars never like starting when warm. Mine fireS straight away when cold but is a pig to start again thereafter. I was told that engaging the clutch when starting makes it easier for the engine to turn over and therefore aids starting so is a tactic i always deploy.. 

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Thanks Mike,  I assume when you say engage the clutch you mean press it down when starting so the starter is not turning the gearbox as well.  This is something I always do to ensure the starter is not doing extra work.

 

Thanks for your input.

 

Alec

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Hi Alex

I'd be inclined to agree with John D, it may be that your starting technique that is making matters worse. Firstly starting from cold with twin dells - common practice is not to use the choke, two or three pumps of the throttle is usually enough to start without flooding. Hot starting can be tricky the usual technique although counter intuitive is to hold the throttle wide open until the engine fires - resist the temptation to take your foot off the throttle. This would help if you are getting a vapour build up. Trying to hot start with the throttle butterfly's closed is not likely to be successful. Good luck

John

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Thanks John,

 

I am sure you are all correct.  I have never owned or driven a lotus before and I have just gor the car through its MOT.  It will probably take me a while to get used to its characteristics and your advice and tips are very much appreciated.

I will use the techniques you suggest and see how I get on.

 

Thanks for your help.

 

Alec

Edited by Alec Grimsey

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As John say the cold starting procedure is 2 or 3 pumps with no fuel enrichment (choke). The reason is although the lever inside can be down the spring that returns the fuel enrichment on the carbs can be stuck open so you can be running with it on all the time.

 

From my users manual I find the hot starting technique works for me. It says depress the accelerator approx. one inch and turn over.

 

Buddsy

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Every car starts easily once you have 40 years of experience in the vagaries of the internal combustion engine (!)...you develop a feel for whether it has too much or too little fuel, or if you've flooded it (or someone else has!) My S3 turbo will not start from cold with the "No choke, 2 or 3 pumps" technique...but fires first time using no throttle and full choke...then leave her to run for 30 seconds or so before returning the choke and opening the throttle a bit. My old Alfa Bertone GTV ( twin 40 DCOE Webers) wouldn't start using the choke, and a couple of pumps got her running immediately. It's "horses for courses" and feel and keep thinking...after a bit it becomes second nature.....

If the starting device sticks on, you'll know all about it as the 'orribly rich mixture is obvious once you drive it...and if does stick, stop it from sticking!!

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I've always done three pumps and no choke, even after the car has sat for two months. My idle is set at 1100 rpm which helps the cold start. Setting the idle slightly higher helps circulate the coolant a bit better when your sitting at a light or in a jam, which is rare. Hot starts I don't do anything, just turn the key.

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Hi Alec,

I understand the carbs were causing the car to run rich, but have you pulled the plugs to check all is ok now?

 

I had a rolling road session recently, then a second subsequnetly (as I wasn't happy with the first), and I was informed the previous guys had set it too lean!

Also, I would advise against starting the engine with the clutch depressed. Yes, it does take some strain off the starter, but don't forget, the crank is being pushed against the thrust washers dry, before the oil has had a chance to soak them.

 

Cold starts, as everyone says, 2 -3 stabs on the throttle. Then hot starts should be about feel - turn over on starter and gently apply throttle if needed.

Are you running original ignition, or is it a Lumition type? you could check condensor, ballast resistor etc.

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Thanks everyone, I think you are all correct and it is basically my technique.  Paul the ignition is standard points and I think with time and practice I will get the hang of it.

 

Thank you so much for all your help.

 

Alec

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