Loctite 518

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Cripes, bit pricey this stuff! Are there any suitable alternatives that are a bit more reasonable? Also, where do you get the little short haired rollers to apply it with from?
 
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Lottie products are probably the best out there, hence the price.
I guess it depends on what you are doing, really......for gasket less sumps then I use Wurth gasket gel, about £6 per big tube from a motor factor.
What are you up to now?
John :)
 
Thanks Burnerman, I'm doing a cylinder head on a Renault Megane, or at least thinking about it, and the Haynes recommends the the Loctite 518 for the rocker cover and oil separator (off the top of my head). The important point seems to be that it's anaerobic which the Wurth gasket gel you cite seems to be. My local factors don't seem to know what anaerobic means and only have silicone based products!
 
Certainly I would have thought that the Wurth product would be fine up there, used sparingly of course!
Has the head gasket blown on the Megane?
John :)
 
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I remember, just read that post again.
I'm just wondering if the engine has ingested something metal, causing those metal shards, and damaging a valve.
There's a crazy idea on some engines (some BMW and Vauxhall ) where there are flaps in the inlet tracts to help with emissions, and on occasion they get sucked in. I don't think that applies with Renault though.
Do keep us updated, and we'd appreciate the odd pic!
Hope the job goes well.
John :)
 
Hello friends! Just making a start on this job now, and have a first little issue. With the timing pin in and locking at TDC on No 1, the slots in the camshafts for the special locking tool do not quite line up. I can get the tool in both with a bit of forcing, but i was expecting them to line up a bit better than they are doing. Is this about right, or are the cams maybe a tooth out of sync? I'm hoping that when I put it all together again, as long as the cams are locked and the pin in it should be ok.

Also, I've read here and there that although you can't crack the crank bolt using the timing pin, (presumably the crank would be coming up to meet the pin from the side. I'll use the flywheel ring gear to lock it), it's ok to tighten the crank bolt against the pin. Will it take it? It's pretty tight.
 
Does the pulley have a slight alignment adjustment? If so loosen the bolts and alignment tool should slide in fairly easily.
 
Don't use the locking pins to lock the motor......they won't stand the strain unless you are using a windy gun!
If you are using an ordinary socket, put the car in a high gear, get someone to stand on the brake pedal as you heave away.
The belt timing won't be a full tooth out, I'm sure.
John :)
 
Ive never had any trouble with the Loctite 5980 although it is silicone based.
Where most people go wrong is putting far too much on, only a light smear is needed.
 
That's the method I used John, with the helper holding it on the brakes that is, the crank bolt was quite easy actually.

AlanE, the cam sprockets on these motors sit freely on the cams and it's just the tightened nuts that hold them together. Ditto the crank sprocket apparently, although I don't need to take that off for this job.

I'm happy that I'll be able to do the valve timing now, I've got a nice set of Laser tools for this engine for locking the cam pulleys together before tightening while the other end is held by the slots. Still haven't got the head off though! I'll see what horrors doing that reveals tomorrow. Thanks gents :D
 
Ok! I think we can all see why my No 2 cylinder compression was a bit low! Blimey!


So, next thing, should I just replace the two burnt ones, or replace the whole lot? And doesn't the whole head look a bit sooty? I'm surprised this sort of damage has happened on such a youthful motor really, is it likely to be running lean to cause this? I'll welcome any input on this.....
 
Hells bells it's a while since I've seen both valves burnt out......normally it's the ignition timing or an excessively weak mixture that causes this but theoretically these days it can't happen. Another cause is the valve not seating correctly for one reason or another.
It's the exhaust valves that cop it due to the higher temperatures involved.
I'd definitely check all of the exhaust valves.....indeed, pop all of the valves out for a stem clean.
A wild, wild guess points me towards the use of supermarket fuel, maybe incorrect plugs.....I don't know.
Hopefully the valve seats are ok......being made from stellite they are super hard - but will clean up with fine cutting paste.
Thanks for showing us this......over to the others for a while!
John :)
 
Ive never had any trouble with the Loctite 5980 although it is silicone based.
Where most people go wrong is putting far too much on, only a light smear is needed.

Sorry ch427, I missed this post until now! I guess that's the point of the anaerobic aspect of some sealants in that any excess silicone will solidify in air and risk blocking oilways, whereas excess of the 518 and similar won't actually cure and do any damage?
 
I'd definitely check all of the exhaust valves.....indeed, pop all of the valves out for a stem clean.

Hi John, can you flesh this out a bit for me? What does a stem clean entail, is there anything special I should be using on them? And what should I be looking for on the valve heads themselves, is there a wear limit on them? I suppose I can compare them all to a new one if I just initially buy the two obvious duff ones first, my local factor has a full set on the shelf anyway. And is it worth lapping in all 16 valves anyway, even if I'm reusing them?
 
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