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83 Eclat - Misfire / rough running, what to check

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Hi Gents, 

I finally bought my first lotus, an 83 Eclat, its been sitting in a dry garage since 92.

Im at the point where everything is done, new belts, distributor, leads, starter motor, plugs etc.

The car starts relatively easily but runs rough and lumpy, if i let it get up to temp and take the choke off it idles okay but the engine shakes as it does so.


So some questions:

1) Is there a default rotation for the distributor housing?I set it based on where TDC is, and then put the other leads in following the rotation of the rotor. So does it matter which rotation the distributor is?

2) How should i setup the carbs? i gave it a quick clean with carb cleaner but have no idea what to do next.


Thanks :-)




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Firstly, welcome to the eclat excel club - an 83 with the grey bumpers, original wheel and speedlines is now a pretty rare car. I have one in ice blue which I have just sold.

1) No. You can set it to TDC and align it on the auxilliary drive however you wish, as long as the rotor arm points to the pole for cylinder one at TDC, you can put it in however you wish, its having it timed up correctly that counts.

2) Carb float height is critical on these Dellortos. - Do a search on how to set them. I had some rough running issues that were immediately cured by setting the floats - despite the bowls being full of fuel on inspection.

the top 4 jets are reasonably easy to whip out and clean them with a pin, and blow through.

Another thing to look for is the MISAB washers between the carbs and the inlet manifold - with age they can perish and fail causing a vacuum leak which makes your car run badly. A knowledgable friend told me the carbs should never be bolted up to the manifold too tight - they should wiggle when you move them by hand.

There is quite a good bit of information on here about setting carbs - youtube also.

NB - headlining always fall down - a friend on here has bought a headlining from another car, and simply cut it into rectangles that get held up by the cant rails. - Much cheaper than resticking fabric and foam to the roof which will just fall down again in a year or so.


We need to talk about that Porsche.




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Thanks Dunc,

I will get onto that right away and let you know how i get on.

Nice to hear the car is rare, i knew nothing about it, but it seems very original and i want to keep it that way. Its only 60k miles too.

One thing thats odd is the front of the car says 'eclat' but the sides say excel, is this normal?

Your spot on with the headlining, i've done a few in the past and have ordered some alcantara in the correct colour so will retrim the roof and side panels. Your suggestion with the rails makes a lot of sense, i'll look into it :-)

Porsche's, we have a few :-)

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Welcome James

Nice looking car (but I can only see the first picture for some reason?) well done and good luck with it.

I've got my carbs to do before long so it will be interesting to hear how you progress. Eurocarb do a full refurb kit for about £70 so I'm going down that route as mine hasn't been on the road since '99. I'm also hoping to soda blast the bodies - I've got the soda and air kit so will try and mock something up as per youtube (where would we be without it :))

You need to quiz Dunc about repairing the small tear in your seat fabric - he has experience!



Is the price for that bit in Yen or £?

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Yes, it is normal for an early excel to be badged as "eclat excel". (which is what it is).

Although the type 89 excel was essentially all new when launched in 1982 and shared relatively few parts with its predecessor the eclat Series 2, Lotus avoided type approval on the new model by calling it "eclat excel". The later cars are badged and known simply as excel - but a most of them will say "eclat excel" on the V5. I believe some simply say "eclat".

You might be surprised how good that split will look with some black thread and a curved needle. My repair wasn't quite invisible, but I was happy with it.

You didn't say which area you are in James?

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Yes, Jack it up on axle stands.

remove the rear wheels (for safety).

put it in second gear and start it up. Holding the clutch down, yank sharply on the handbrake. It'll take a while. You will know when it is free when the speedo needle drops to zero with the clutch in.

Some people use the footbrake, but it has one of those stupid bias valves which seems to make the rear brakes almost ineffective, and using the hanbrake saves you needing 3 legs.


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7 hours ago, Dunc said:

but a most of them will say "eclat excel" on the V5. I believe some simply say "eclat".

My 1987 Excel SE had "Éclat Excel" on the V5, whereas my 1989 Excel SE has "Éclat" on the V5

No wonder the HowManyLeft site has more Eclats than Excels left for 2015

Éclat: Licenced: 209, SORN 413
Excel: Licenced: 158, SORN: 247

James - Come along to the Herts/Essex/Cams meet next Thursday if you can. There'll be a post up about it over the weekend in the this area



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Quick update, followed a tutorial on setting the float level which has greatly improved the running, its considerably smoother at idle, also blasted the jets with carb cleaner.

The joint between the carbs and inlet manifold is stiff as aunt nelly, so i will disassemble and get a new spacer / whatever its called.

Also noticed that one carb as a really tin flimsy gasket whereas the other has a ticker stiffer one, so will get a matching set.

@Dunc - thats a fantastic solution, everywhere else i looked it was suggesting trying to drive it around, but thats near impossible in basildon as we have roundabouts, crossings and traffic lights every few meters, i will definitely do that :-)

@Chris - great, i will be there :-)


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Hi James , A clutch release trick given to me by an old mechanic that's always worked and is handy if your on your own or limited

space is to

1, hand brake off

2,wedge the clutch pedal down using piece of wood against the seat bolster [protected ]

3,select third gear ,then push/rock the car backwards a few times ,you might have to alternate with a few pushes forward

if you hear a squeak and a clank and it starts free wheeling then you know your home and dry

its worth a try best of luck  Ian

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Hi Guys,

So, some updates, good news first:

Clutch is finally free, thanks for all the tips :-)

Bad news - clutch pedal snapped :-(

I was struggling to depress the pedal enough to engage gears despite the clutch being free, so with a few pushes and pumps it snapped clean :-( (in fairness it was already bent back, so likely fatigued by the previous owner)

So began the laborious task of getting the pedal box out, and welding up the pedal, in the process i corrected it to original position, not bent back.


This is a far more difficult task that it may at first seem, i had to remove the steering column, most of the dash, and a lot of carpet and trim.


What did frustrate me was where you would expect the use of bolts and a threaded panel, instead there would be nuts and bolts through panels where you do not have access to both at the same time, two sets in this case, near impossible to do without a second person to hold stuff still, did cheese me off.

On the plus side all the electrical plugs - and everything under the dash in general were really good condition.


While there i took the opportunity to inspect the brakes, steering rack boots. Brakes are good condition, sadly the boots had disintegrated with age when i touched them but they are easy to sort.

Please excuse the tatty carpet, i've had a whole set made and am waiting for it to arrive, along with headlining.

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While you have the pedal box out its worth looking at the clutch cable pulley, mine had seized and the cable was slowly sawing through it!

I replaced the cheap nylon pulley with an aluminium one i had from a boat pulley, its much smoother now, although i did look at nylon pulleys with a ball race bearing available on ebay.

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So Gents,

I am in need of your wisdom once again.

So  when i finally managed to release the clutch - and was able to move through the gears while disengaged - the salve cylinder got stuck at the top of its travel, holding the clutch disengaged.

After fitting a new slave, i am now stuck with the issue that the clutch lever is so stiff to move that i danger breaking the pedal (again) to depress it.

I got underneath the car to inspect and the lever does move around freely from side to size and back and forth a few mm, is this correct? or has something gone wrong with this mechanism?

The mechanism is definitely not seized - just very very hard to push.

So question for ten points - is the engine coming out?

- some slightly off topic good news, the chassis is spotless, no corrosion what so ever, dead pleased

Edited by Cabbage
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@Dunc - yes the new one works fine, what do you think my next step should be? is it an engine out job to inspect properly? if so engine and gearbox together?

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  • 5 weeks later...

Engine out finally :-)

So, freed everything up and smothered grease where required.

While its apart it makes sense to fit a new clutch, problem is where from? Mine says Borg and Berk 57186 but I can't find this anywhere, any tips?



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Just back to the carbs for a minute if I may, 1 item often overlooked is setting the balance of the carbs.

Unfortunately, some specialist equipment, a Synchrometer, is required. These can be purchased for as little as £30 and are invaluable for as long as you have a twin carb engine. If you are into your DIY there are plenty of tips on line on how to make a homemade Manometer.

Search for " Balancing Dellorto & Weber Carburetor by Tim Engel " and you will have some valuable information on setting your carbs.

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2 hours ago, Cabbage said:

Got a new clutch, ordered via SJ and arrived the next day :-) time to put it all back together

I would also recommend you replace the clutch cable. For it too snap a pedal would mean that the cable was put under some serious, abnormal, pressure. Before you refit the engine, you should also check the clutch fork mechanism and release bearing. Its not unusual for the selector fork to slip from its pivot point.

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All good advice Michael, but Lotus changed it to hydraulic actuation when they launched the excel, which removed a potential problem area.

I believe the clutch plate is from a toyota hi-ace, but I'm told its no cheaper getting it from toyota than getting one for a Lotus from Lotusbits or SJ sportcars.


Sounds like your having fun James!

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