620s - Engine cutting out in very heavy rain

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Phillip Meyer
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620s - Engine cutting out in very heavy rain

I was caught in a tropical style downpour today whilst stuck in traffic. The Caterham really didn't like it and was not running smoothly after a short while, seemed to be misfiring and a bad smell. I managed to bunny hop to a fuel station and hide under their roof. It seemed tO be okay after drying out but then I had the same problem again after the rain stopped but with very wet roads.

I'm currently waiting for it to dry out a second time, fingers crossed it will be okay now the sun is out.

However, should i by worried that it's done some damage?

Any thoughts on the cause so I can avoid this happening again if caught in the rain?

Jonathan Kay
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IIRC the most commonly reported cause is water in the recess above the spark plug. But I can't remember which engines were affected.

https://www.lotus7.club/forum/techtalk/plugs-and-duratech-warning
https://www.google.co.uk/search?&q=rain+sigma+plug+site:lotus7.club

Jonathan

Piers300
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Chances are that the plug wells will be full of water.

Remove everything needed to get in there and dry it out.

 

Piers

SM25T
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Once water gets in to plug wells, it can't escape as rubber caps prevent it evaporating. Have to remove each cap and use paper towel. That's my experience with a flood and a k-series engine.
aerobod
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From the symptoms (especially the bad smell comment), it may be a case that water has got into the lambda sensor connector or wiring, too.

James

Phillip Meyer
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It was insanely wet, like a tropical storm, good job I only had the aeroscreen on!

It worked better after a while but then I had the problem intermittently all the way home until it stalled about 10 mins from home. Then after a restart worked absolutely flawlessly which is Also odd.

Piers300
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As Ian says (#4).  You need to get in there and dry it out. Obviously, don't take out the spark plugs till completely dry.

Piers

Phillip Meyer
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I have to figure out how to get at them first, I had a look earlier and it didn't seem obvious. Needless to say, I haven't built a Caterham!

Blue7
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I don't understand how rainwater is getting into the plug wells unless a coil cover has not been fitted?  I thought all 620S had a coil cover?

Benton
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#8  Just checked mine as I was caught in a biblical storm this morning coming back from CC Gatwick, and fortunately they were dry as a bone. Given the lip/rubber seal tightness on my coils to get water down to the plugs you'd really have to be unlucky.

To check.....

Remove coil cover, 2 torx screws, watch out for the fibre washers that are either side of the cover for the screw


Remove individual coils,  undo 8mm bolt and pull.

Look down hole Wink

Good luck!

 

John Vine
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I'm inclined to agree with James (#5), especially re the smell.

JV