Since I bought the Rover 414 it's had a manky thread on the fourth plug.
Last night the moment I've been dreading occured and that cylinder stopped firing.
Changing the plugs was the last straw for the thread and after getting it in as best I could I fired it into the bonnet. ;-(
So I now need an in situ solution 'cos I don't want to take the head off.
To complicate matters I worried that the plug wasn't properly located before and that I've melted the aliminum head closing up the plug hole. (I cant get the plug more than half a centimetre in)
1) Is helicoiling the solution?
2) Can anyone recomend a place near Horley, Surrey that will do it.
3) Can anyone recomend a mobile spanner man with a van that would do it at my home address.
4) Can anyone explain the process? I'm assured it can be done in situ but surely the old thread would need to be drilled?
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Called a garage. Said the job was easy - just bring it in. I was a bit suspisious.
Called another place who had a good old chat.
He say it's hard. The helicoil tool isn't long enough but he is prepared to try on a hit and miss basis.
He says rusty plugs in 414's *are* a sign of head gasket woes. The bolts go all the way through and stretch with time.
Anyone got any thoughts? This car has always eaten plugs.
My regular spliting plug problem (regulars will remember this) *could* have been water accumulating under the plug and freezing spliting the insulation.
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Just spoke to someone else who said never helicoil plug threads.
Really need the wisdom of this site here.
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Dave,
Sorry to hear of your troubles. Going to be a bit negative here I'm afraid!
You may find the plug won't go in far now because of the manky thread left in the head.
If a plug is screwed right home the thread has to be terrible to fire the plug out. I wonder if before you only screwed the plug part way in before it seemed tight . Then it fired out because only part of the thread was hanging on.
If you have any thread left to work with Sykes do plug thread "chaser" tool that will square up a dodgy thread quite well. If you are selling the car then a bit of loktite/bearing fit as well and you're away.
Helicoiling is an option and some may well advise it. I have seen the helicoil come out with the plug next time it is removed several times so would be wary.
All depends on costs. How much do they want for a helicoil? Rover heads/engines/whole cars are plentiful and cheap so replacement may be a better long term option.
Note: If I'm ever buying a s/hand engine/head I always take a spark plug spanner and check the threads, saves that sinking feeling at home.
Really I hope others come back to tell you helicoils are brilliant, you get it done tomorrow for £35 and run the car for another 50,000mls without trouble!
David
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Dave,
OK you're desparate, here's what I might do on my own older car.
Have a look with a little torch down the plug hole. If there is a reasonable amount of thread (manky or not) then nip out and get a plug thread chaser (they're only about £8) and do the best with that.
Also get some bearing fit, loktite or similar wonder chemical...and some new plugs.
Get the new plug in first time and then don't worry about it for 12,000 miles plus. If there is a triple electrode plug for your car then you're fine for 20,000 plus.
If this works you've got some thinking time, if not it's only cost a tenner for the tool.
By the way there is a DIY version of the tool. Get an old plug and make a saw cut down each side at right angles to the thread. Screw this in with plenty of oil, making sure it is dead square first time. It could just clean up the thread enough for a decent grip with the aforementioned miracle "glues".
The disadvantage to all these methods in-situ is you can't be totally sure what might have dropped into the cylinder during the attempt.
Hence my previous comments about a replacement head etc.
David
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David W wrote:
> By the way there is a DIY version of the tool. Get an old
> plug and make a saw cut down each side at right angles to the
> thread. Screw this in with plenty of oil, making sure it is
> dead square first time. It could just clean up the thread
> enough for a decent grip with the aforementioned miracle
> "glues".
I tried this last night David. A right struggle just to make the 'tool' & still no joy.
I'm tempted to go for the new head or removing the existing head for the repair. (20 quid with the head off.) Especially since rusty plugs mihgt mean suspect head gasket. (OTOH it does a lot of short journeys)
However I'm a little daunted by doing it myself due to cylinder sleeves and setting the timing up afterwards. I'm assuming th and the cost of getting a 3rd party to do this is gonna be high
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Dave,
The trade time for this head/gasket is about 5 hours. Add to that new coolant/timing belt/gaskets/poss new head bolts etc...and anything else evil found once it comes off. Perhaps £200 - £400 depending on the place.
If you are going to have the head off think hard about the helicoil vs a s/hand head with decent threads. There is just a chance that the helicoil will come out in the future and you'll be doing it all again.
You should be able to do this job with the assistance of a Haynes manual. Just follow all the steps carefully. With particular regard to cracking off the head at an angle so as not to disturb the liners, not trying to turn the engine over with the head off, re-torque figures/sequence for head bolts, head bolt stretch checks and finally timing the engine.
David
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David W wrote:
> The trade time for this head/gasket is about 5 hours. Add to
> that new coolant/timing belt/gaskets/poss new head bolts
> etc...and anything else evil found once it comes off. Perhaps
> £200 - £400 depending on the place.
For 200 I'd get someone else to do it. I'd need to find a second hand head from somewhere.
> If you are going to have the head off think hard about the
> helicoil vs a s/hand head with decent threads. There is just
> a chance that the helicoil will come out in the future and
> you'll be doing it all again.
Yeah - if the head came off I'd be either taking it to an engineering company and getting it doen right or buying a used head.
> You should be able to do this job with the assistance of a
> Haynes manual. Just follow all the steps carefully. With
> particular regard to cracking off the head at an angle so as
> not to disturb the liners, not trying to turn the engine over
> with the head off, re-torque figures/sequence for head bolts,
> head bolt stretch checks and finally timing the engine.
I've read up on how to do it in the Haynes Man. Timing and liners seem daunting.
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Right.
I've found one guy who both understands significant problems of helicoiling but still prepared to try it (at my risk).
He'll try for 45 quid.
So I'm taking a 45 quid bet that there is no gasket leak and this guy can do it.
Added to this I'm moving house next week!!!
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problem number three is the wife coming with you or staying put.
Best of luck with the car though
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andy bairsto wrote:
>
> problem number three is the wife coming with you or staying
> put.
I'm not married - so at least I've got lot's of cash to throw at the problem!!!
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A company called 'Staines Deisels Ltd.', a.k.a. Runneymede Engine Centre, did our Audi 80 cylinder head - the two centre plugs just turned when I tried to take them out.
I supplied them the head off the car. They did not use 'helicoils' as such, which are loose metal coils screwed into an enlarged threaded hole with a special tool, but used a solid one-piece insert inserted each machined-out hole and secured with loctite. They charged £35.00 plus VAT back in 1998.
Tel. 01784 437228/433832/438925 Fax. 01784 430690
BTW, if you machine out the hole to fit the helicoil with the head 'in-situ', you will fill the cylinder with swarf! Also, when a helicoil is fitted the 'tang' that locates the helicoil on the insetion tool must be snapped off, by bashing the tool centre rod with a hammer, and this will also fall into the cylinder. Good luck getting all that stuff out....
Martin.
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Martin wrote:
>
Also,
> when a helicoil is fitted the 'tang' that locates the
> helicoil on the insetion tool must be snapped off, by bashing
> the tool centre rod with a hammer, and this will also fall
> into the cylinder.
If I try the heilcoil and *if* it falls in the cylinder I will have to remove the cylinder head to get it out - which is exactly what I'll have to do if I don't try the helicoil.
I'm not totally happy with the Helicoil route but it's an old car and could save me a lot of time and effort.
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I guess what i'm trying to say is - take the head off!
Good luck with whatever you try.
Martin.
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