Rover 414i Rusting/Split Spark Plugs.

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Fri 17 May 2002 11:38
Rover 414i Rusting/Split Spark Plugs. - Toad, of Toad Hall.
Those who've been around a while will remember Dave had a problem 12-6 months ago with a) Spark Plugs Rusting & b) No 2 Cyl sparker insulation spliting.

Nobody could explain it and we put it down to dodgy champion sparkers in the end.

Well. Tuesday morning I got that 3 cylinder start from cold that I know to be a split plug.

Bought an individul NGK and whipped the old Cylinder two NGK out. It's rusted away significantly and the insulation is completely split.

Also the other two plugs than I dare touch [1] are rusted solid into their sockets (since October). You'll have to trust me on this. I know the car nad I know well the 'springy' feeling through the breaker bar that says 'Put another ft/lb on me and I'm gonna bring the thread out with me'.

After 3 years and 20k miles this car is effectively scrap and on borrowed time. Investing another few hundred on another one when it dies is not a problem so I'm not concerned about curing any problems but, from an academic point of view I'd love to know:

1) What splits that No 2 plug?
2) What rusts the plugs? [2] I used to do two 1.5 mile runs a day but there's been no short runs now since October.
3) Is it possible to free the solid plugs? WD40, pouring engine oil down? [2]
4) Compression on No 2 is 90. Good or Bad?


[1] 1 & 3. No 4 is Helicolied and will remain untouched for ever. ;-)
[2] Beyond the Aluminium/Iron rust battery interface there must be some something else. 6 months for plugs to rust in solid is crazy. [4]
[3] Ok Q3 isn't academic. I'd love a look at em!
[4] I haven't previously ised copperslip, but will from now on, of course.



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Parp, Parp!
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Fri 17 May 2002 11:46
Rover 414i Rusting/Split Spark Plugs. - Toad, of Toad Hall.
"are rusted solid into their sockets (since October)"

I meant 'have rusted in since October'. In other words they were free in october and are now solid.

I don't put them in too tight.


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Parp, Parp!
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Fri 17 May 2002 13:42
Rover 414i Rusting/Split Spark Plugs. - M.M
Toad,

Don't say too much in case you want to put it in Classifieds as a bargain....without anyone poking fun ;-)

How do you mean the plugs are "rusted" in. I thought the head was alloy and the plugs a plated finish.

90psi sounds low to me for compresion, I haven't the exact figure for your engine but it should be much nearer 150.

So are *we* going to choose your *new* car soon then?

David W
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Fri 17 May 2002 14:14
Rover 414i Rusting/Split Spark Plugs. - Toad, of Toad Hall.
Don't say too much in case you want to put it
in Classifieds as a bargain....without anyone poking fun ;-)


Don't give me ideas DW. ;-) 'Never raced or rallied!' If someone wanted it I'd give it away *but* it drives badly and has various bodywork dings & is regularly soaked in salt water from windsurfing. That said I've got a photo of the clocks at 110mph and 5300 revs so I can proove it still goes like stink!
How do you mean the plugs are "rusted" in. I thought
the head was alloy and the plugs a plated finish.


Well I don't over tighten them and they're stuck tight. The last one I forced out brought the thread with it! I assumed that was rust. Am I wrong? What else 'sticks' plugs in place to that extent? It doesn't run hot so I doubt they're melted. It can't be a major mechanical problem 'cos it's done 20k eating plugs in this way!

The plugs are a dark red colour that doens't match my Haynes manual plug chart. The metal itself is eaten away round the electrode end of the plug. I assumed this was rust but it could be anything!
90psi sounds low to me for compresion, I haven't the exact
figure for your engine but it should be much nearer 150.


Sweet! Whats the record for the lowest compression for a running car! I want that trophy!
So are *we* going to choose your *new* car soon then?


Mr Moorey said it was on it's last legs over 6 months and 3 road rallies ago! [1] Against the best medical opinion available this car is gonna soldier on a few more miles.

But yeah. It won't be long now before something critical or expensive [1] goes so get your thinking hats on!

Oddly enough it only loses about 1 litre of oil every 1k miles which doesn't seem excessive!

[1] Nothing like an italian tune up as a cure for extreme engine wear!
[2] I won't spend more than a tank of petrol on a maintainance item now.



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Parp, Parp!
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Fri 17 May 2002 14:30
Rover 414i Rusting/Split Spark Plugs. - terryb
I'm a firm believer in WD40 and a cup of coffee or two while it has time to penetrate. Never tried it on spark plugs but it's worked for me on everything else I've tried.
Terry :o)
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Fri 17 May 2002 14:37
Rover 414i Rusting/Split Spark Plugs. - Toad, of Toad Hall.
I'm a firm believer in WD40 and a cup of coffee
or two while it has time to penetrate. Never tried it
on spark plugs but it's worked for me on everything else
I've tried.



I can't see quite how it would soak in *but* it's all I can think of too so I'll give it a go!

I've been treating some bike exhaust studs in this way ready for the weekend.

Not going to sweat to much about this. HJ's Mondeo with 107k at 2 grand at auction seems like a barg.


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Parp, Parp!
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Fri 17 May 2002 14:52
Rover 414i Rusting/Split Spark Plugs. - Matt
The saltwater you mentioned may have something to do with the rust-I always WD40 (the single best invention for car/boat maintainance?) the exposed part of the plugs when replaced as the saline road conditions in England can murder unprotected engine parts.
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Fri 17 May 2002 14:54
Rover 414i Rusting/Split Spark Plugs. - terryb
Toad
No, I don't understand it either but a combination of capillary action and/or gravity has always worked for me in the past - last time was last weekend with a corroded screw in the caravan water heater.

Terry
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Fri 17 May 2002 15:00
Rover 414i Rusting/Split Spark Plugs. - Toad, of Toad Hall.
Toad
No, I don't understand it either but a combination of capillary
action and/or gravity has always worked for me in the past


Ditto! I've used it on countless bolts which in theory ought to be as watertight as a plug!


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Parp, Parp!
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Wed 30 Oct 2002 18:16
Rover 414i Rusting/Split Spark Plugs. - madf
I have used WD40 but for really BAD aluminium to iron corrosion, Vinegar is better.

I used it to move the thermostat housing on a Mark3 (1981) Jaguar XJ6. The thermostat had jammed shut (steam!) and one of the studs sheared. The other 2 were solid. I removed the entire manifold, and soaked it in vineagr. then I went away for the weekend.

Worked a treat: vinegar dissoves oxides of aluminium/iron...
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Wed 30 Oct 2002 18:30
Rover 414i Rusting/Split Spark Plugs. - Toad, of Toad Hall.
Oddly enough, Madf, I got the other plugs out literally a couple of weeks ago. (Maybe this should be on the preminition thread!)

I soaked in Plus Gas, BUT, and this is the strange bit. The stuck ones were now no more than finger tight. In May me and another guy had a go and agreed they were too 'springy' to risk. (15 inch breaker bar was 'springing'). Car was cold when they seemed loose, that was the only difference.

Will remeber the vinegar trick.

None have split since May but all are rusty.

Car is up for MOT soon so may have to go.

Over 25k and 3 years. Not bad.




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These are my own opinions, and not necessarily those of all Toads.
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Thu 31 Oct 2002 11:24
Rover 414i Rusting/Split Spark Plugs. - pmh
Threads (unless tapered) are not designed to be sealed, the seal is the the compressed washer or flat mating surfaces. From memory I believe most sparking plugs use parallel threads, notable exceptions being the Ford Fiesta Fisaco.

This will then allow combustion products up the thread, presumably causing the corrosion that locks the thread tight.

How WD40 or sililar will seep down I do not know. Any comments?



pmh (was peter)
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Thu 31 Oct 2002 11:58
Rover 414i Rusting/Split Spark Plugs. - John S
Peter

You are right that the thread on a spark plug does not form the seal. However all spark plugs use parallel threads, even the Valencia engined Fords. These engines (and some others) do however use spark plugs with a tapered seat for sealing (not a tapered thread), rather than the flat seat/washer combination.

Regards

John S
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Sat 21 Dec 2002 22:07
Rover 414i Rusting/Split Spark Plugs. - David Lacey
Never come across a seized plug, but we have had some tight ones!

I know what the Valencia Ford ones can be like.......glad we;re not a Ford Dealership!!

Try removing the offending plug with the engine red-hot, this sometimes helps.

If all else fails, a 3/4" drive impact wrench usually does the trick ;)
MG-Rover Problems? forums.mg-rover.org/
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Sat 21 Dec 2002 23:00
Rover 414i Rusting/Split Spark Plugs. - frostbite
Another alternative is Coca-Cola!

This is often used by professional caterers to restore stained cutlery which is soaked overnight in the stuff and emerges like new.
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Sun 22 Dec 2002 09:41
Rover 414i Rusting/Split Spark Plugs. - David Lacey
Better go out and get some of the REAL thing!
MG-Rover Problems? forums.mg-rover.org/
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