Lotus Elan Central

by **Sy V** » Wed 21.06.2006, 16:21

Oh God!

I used to be Operations Warrant Officer for Storm Shadow.

by **GeoffSmith** » Wed 21.06.2006, 16:35

Yes I know. At Northholt. Until you "retired". We did this about three months ago by e-mail. Come on, keep up you crumbly old fart! :smt043

And before you think of calling me anything worse than a wrinkley, you should maybe consider whether I have a spare round, an MPU and your co-ordinates! Are you feeling lucky? :twisted:

by **Sy V** » Wed 21.06.2006, 16:38

In my defence, it must have been under your old membership name before you lost your login - must have been a memory thing too!

by **GeoffSmith** » Wed 21.06.2006, 16:54

It was actually back in February.
But I've never forgotten a membership name. I don't think. Is it Thursday?! What's for tea?

by **GeoffSmith** » Wed 21.06.2006, 20:53

Anyway, back to the topic, what's melted the end of Paul's plug? (heat is not a valid answer!) Paul, are the other three plugs OK or is there any sign of meltdown?

Geoff

by **Candles** » Wed 21.06.2006, 21:50

geoffsmith wrote:what's melted the end of Paul's plug?
Geoff

Could it be that the fluid (water/oil) leaking into the cylinder created conditions that it couldn't cope with?

Or maybe it has had a water leak for ages and it corroded away; the oily death dealt out recently covered the evidence!

Candles.

by **GeoffSmith** » Wed 21.06.2006, 21:55

My thought was that it looked more melted to a blob than corroded/eroded away. It looks like someone has been using it for welding!

Geoff

by **paulwatkins** » Thu 22.06.2006, 07:22

I have to agree with you Geoff. The end of the plug looks like it has actually melted away as opposed to erroding. The other 3 plugs appear fine, and all the gaps were correct too.
I can only assume - as Candles first suggestion - that the plug has been subjected to this oil / water environment and this is the end result!
I'll try to take a clearer picture of the plug.....best use a tripod this time I think!

by **paulwatkins** » Thu 22.06.2006, 07:23

I have to agree with you Geoff. The end of the plug looks like it has actually melted away as opposed to erroding. The other 3 plugs appear fine, and all the gaps were correct too.
I can only assume - as Candles first suggestion - that the plug has been subjected to this oil / water environment and this is the end result!
I'll try to take a clearer picture of the plug.....best use a tripod this time I think!

by **Candles** » Thu 22.06.2006, 09:40

Don't bother with a tripod, just do it somewhere better lit! Don't hold the camera too close either as it won't focus.

by **delta** » Thu 22.06.2006, 14:15

If the end of only one plug is melted, it just sound like a failur of the injector, running that cylinder way to lean. So beware.!. it can even burn a hole trough the piston.

Can't remember how to test the injectors, but I'm sure there is a procedure for that somewere.

Delta.

by **GeoffSmith** » Thu 22.06.2006, 14:54

delta wrote:If the end of only one plug is melted, it just sound like a failur of the injector, running that cylinder way to lean.

Makes sense to me Delta. I think that coolant/oil getting into the cylinder is more likely to cause erosion. Having said that, if one pot has been running lean, it may well have damaged the head/head gasket as well which has resulted in the oil/water problem.

Compression test would definitely be worthwhile Paul, even if the injectors check out OK - the blockage may only have been temporary.

Geoff

by **paulwatkins** » Thu 22.06.2006, 19:24

Here is a close-up pic of spark plug no. 2. A bit better than my previous effort! You can just make out the 'blob' of metal at the end where it has melted...

by **F1 LOTUS** » Thu 22.06.2006, 21:19

Have you tried fitting a new plug to see if it will start and how it runs?

The centre electrode / insulator doesn't appear to have 'been in the wars'? I'm just wondering if the ground electrodes' failure was more 'mechanical' perhaps caused by a flaw or heavy-handed cleaning

You'll need new plugs anyway?

by **paulwatkins** » Sat 24.06.2006, 11:40

The mechanic called around to do the compression test. This is what he found:
No 1 - 175
No 2 - zero
No 3 - 160
No 4 - 175.
He also carried out a coolant pressure test. No values to give you, but he noted the following:
Ran engine briefly (it was less than 1 minute actually), coolant pressure rising.

He recommended removing the head for further invesyigative work.

F1 LOTUS - I have some new plugs on the way anyway, to replace the damaged one.

by **GeoffSmith** » Sat 24.06.2006, 12:31

Bad luck Paul, looks like head and/or gasket. Are you going to tackle it yourself?

by **delta** » Sat 24.06.2006, 12:36

Oh dear.!.
Prepare your self for a nice hole burned trough the piston.!.
(my guess)
Delta.

by **GeoffSmith** » Sat 24.06.2006, 12:52

I hope you're wrong for Paul's sake Delta!

My reasoning was that, if the coolant is pressurising, there must be some pressure, so for "zero" read underscale. If the piston had been holed, I wouldn't have thought there was sufficient pressure to pump up the coolant.

by **paulwatkins** » Sat 24.06.2006, 17:48

Delta - I hope you're wrong aswell!

Geoff - I am going to tackle the job myself. I'm going to follow the manual and write-up from this site. Take my time, take plenty of pics as I go, label everything up as I remove them and just see how I get on.
I explained this to the mechanic this morning, and he said he would be able to help me out if i got stuck.........watch this space I suppose!

Wish me luck guys, I'm going in!!! Well, think I'll start tomorrow! :lol:

by **Monty** » Sat 24.06.2006, 19:40

Paul,

Bad news on the compression test, did the mechanic say it could still be the head gasket or is it more likely to be the piston rings?

I believe u can take the head off with most stuff still connected. At least u save a few quid by doing it u`r self.

Good luck
Jay

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Engine rebuild project following blown piston

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