Hot-starting issues

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scarecrow

Hot-starting issues

Post by scarecrow »

My 14 has real issues about starting when hot. It always starts, eventually, but then I have to give it a few revs before it will tick over.

I also feel I have to use the choke too often - basically I have to use a bit of choke all of the time unless the engine is fully up to temperature. Having Medway Citroen's 14 for a day has made me realise that this isn't normal.

I've been on a couple of long runs recently and other than the hot-starting the car is fantastic - although acceleration can feel less than smooth, but not in a misfiring kind of way, more in a power band kind of way.

Is this all pointing towards needing a new Carb.?

Other work that has been done includes, two new fuel pumps, new vacuum units on the Dist. and Carb., ignition bits and tappets.
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Post by Dollywobbler »

What about the coil? Overheating coils are a big pain for 2CV owners. Starts fine when cold, won't go when hot.
scarecrow

Post by scarecrow »

I hadn't thought of that - I seem to remember that they are a bit cheaper than a new Carb. too!

I still suspect the Carb. as the engine just doesn't feel quite right and the mechanics I've talked to about it treat me as if I'm an idiot and should just be happy that it goes, if they're not advising me to get a better car! I find that really annoying, I want 'my' mechanics to care.

Is there any way to test a Carb?
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Mike E (uk)
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Post by Mike E (uk) »

Have you checked the air feed to the filter is in the summer position?


Mike
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scarecrow

Post by scarecrow »

Mike E (uk) wrote:Have you checked the air feed to the filter is in the summer position?


Mike
Yes - I'm sure I put it there in the spring, but I'll check again. Thanks.
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electrokid
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Post by electrokid »

Coils can overheat if the dwell angle is wrong but carb is more likely. Some garages will tell you that the carb can distort and could need replacing because of that - that's rubbish - the casting can settle (and therefore distort) within 2 weeks of being cast but not after it's been running properly on the car for yonks. If it's the carb then a recon kit is the cheapest option (google it).

I'm not familiar with the layout of the petrol versions - but if the area has been worked on at any time you may have vapourisation problems - petrol turning to vapour before it gets to the carb - a pipe may have been re-routed too close to something hot or, if fitted in the first place, a heatshield may have been left off.
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Gibbo2286
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Post by Gibbo2286 »

It could be something as simple as weak mixture caused by a carb base gasket or inlet manifold gasket damaged and letting in air. Gibbo.
scarecrow

Post by scarecrow »

Hmmm... all of these things sound plausible - but I had a head gasket pressure test the other week and it was fine.

Using the car today there is a definite not rightness about the engine when not accelerating. It's not very pronounced, but there's a slight jerky feel when holding a steady speed on the flat. Acceleration is pretty good, power kicks in at about 2500 Revs and carries on as far as I've dared to go (5000, maybe :oops: )

Looking at the service history the car did have a head gasket replaced - 10 years ago or so and the exhaust is raspier than Medway's St Tropez, but apparently I'm the only one who can hear this...

A new Carb. is a couple of hundred quid without fitting, so I'll check to see how much a refurbishment kit is.

Thanks for the advice - I'll sort this out even if I end up replacing every engine component piece-by-piece :wink:
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Post by Dollywobbler »

Does sound like a possible air leak. Is there a gasket between carb and engine?
scarecrow

Post by scarecrow »

I'll have a good look over the weekend when I can get the car on my sister's drive.

Would there be any tell-tell signs of a gasket leak that I should look out for?

Thanks
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Tim Leech
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Post by Tim Leech »

Have you tried a good dose of carb cleaner and a new fuel filter?
Lots of Motors, mostly semi broken....
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Way2go
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Post by Way2go »

The problems you describe are similar to what I experienced many years ago on a different engine. I too had explored problems with the carburation and ignition but the root cause on deeper examination was that 3 of the exhaust valves had burnt away at their sides.

It may be worth doing a compression test on each cylinder to check the integrity of your valves.
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Post by Dollywobbler »

A simple test is to squirt WD40 around the base of the carb. If the revs go up, it's sucking the oil in.
scarecrow

Post by scarecrow »

Way2go wrote:The problems you describe are similar to what I experienced many years ago on a different engine. I too had explored problems with the carburation and ignition but the root cause on deeper examination was that 3 of the exhaust valves had burnt away at their sides.

It may be worth doing a compression test on each cylinder to check the integrity of your valves.

And if the tappets were over adjusted... hmmm

Thanks for the other advice too - I have noticed a strong smell of petrol when parking up on very hot days so that is an issue - I'll check the filter, but hard acceleration is pretty good, it's all the rest of the time that it's not quite right.

I love the wd40 test - thanks for that, I'll give it a go in the morning.
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electrokid
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Post by electrokid »

I love the wd40 test - thanks for that, I'll give it a go in the morning


Yes that's a good one -another way is to use a piece of windscreen washer tubing as a stethescope - one end in your ear and the other end searching around gaskets etc to listen for a hissing sound.
a strong smell of petrol when parking up on very hot days
Sounds like the anti-stall diaphram (which will be in the recon kit) perforated. There's a vacuum connection to the carb - first find it. A number of ways to check it - take off the pipe connection at the carb end - there should be no petrol inside the pipe - if there is then the diaphram is leaking - a temporary fix is to block the pipe with something solid and put it back onto the carb - don't run the engine with it off or petrol will pee everywhere.

Another way - with the engine running and if there'e enough length in that vacuum pipe to do it safely and easily - bend the pipe double (to block the pipe) and if the engine note changes then the diaphram is leaking. With this test, if the engine stalls immediately then someone has adjusted the mixture at some time - not knowing that the anti-stall device was faulty - the adjustment will have covered up the fault to an extent. If you run with the vacuum pipe blocked you may have to re-adjust the mixture to get the engine on-song again. You won't have the anti-stall facility so when you come off the gas it may stall - but this is why the anti-stall is fitted in the first place.
1992 BX19 TGD estate 228K Rusty - SORNed
2002 C5 HDi SX estate
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