Omega Owners Forum

Omega Help Area => Omega General Help => Topic started by: vauxox on 18 February 2010, 15:37:13

Title: oil cooler
Post by: vauxox on 18 February 2010, 15:37:13
hi just about to do my oil cooler can anyone tell me if there is a sealant that i can use apart from vauxhall grey i read somewhere that you have to use this and leave for 24hrs is this true i would be gratefull if anyone can give some advice
Title: Re: oil cooler
Post by: Marks DTM Calib on 18 February 2010, 16:04:11
There is a loctite alternative (cant remember what it is though), hermatite (none of the varients) is good enough in my opinion.

Vx is the best place though....

As for 24 hours, yes it is prefered but, can be used after 1 or 2 in reality
Title: Re: oil cooler
Post by: vauxox on 18 February 2010, 16:54:39
thanks just thought id save myself a trip to the dealers but maybe false economy thanks for letting me know
Title: Re: oil cooler
Post by: Cliffo B on 18 February 2010, 17:55:46
Dont use any thing else but the GM product. Make sure the mateing flanges are super clean. I used a combination of 360 grade wet or dry and finished with medium Scotchbrite. Try and avoid deep scratches. Then finish off with a good clean, useing celly thinners or a similar degreasant, to give virgin grease free flanges ready to accept this special sealant. Leave to set as long as possible. I would  consider at least overnight for a reasonable cure.Hope you do Ok.
Title: Re: oil cooler
Post by: vauxox on 20 February 2010, 00:37:44
thank you
Title: Re: oil cooler
Post by: vauxox on 20 February 2010, 00:39:10
i will let you know the outcome
Title: Re: oil cooler
Post by: biggriffin on 20 February 2010, 09:05:37
i use good ol silicone from b+q use it every were exuast gaskets,rocker covers, and oil cooler half the price twice as good. if its a quality silicone sealer its better, its stable up to about 900.c  never had a problem with it yet. go on try it. o and by the way its not genuine vx ;D
Title: Re: oil cooler
Post by: ScottieMV6 on 20 February 2010, 15:05:33
Correct me if I am wrong but the proper stuff from Vauxhall is £8 a tube (just checked my invoice). Good quality sealant in B&Q is about £8 a tube (not sure how that is half the price). I fail to see how anything is better than the stuff the manufacturer uses without any problems :-X
Title: Re: oil cooler
Post by: Kevin Wood on 21 February 2010, 00:39:36
Good quality sealant in B&Q is designed for putting round your bath not for sealing coolant under pressure in an engine!

It will also give off fumes which can kill a Lambda sensor when used on cam covers, etc. It will break down on contact with hot oil over prolonged periods and can end up blocking the oil pickup, perhaps lunching the engine.

At least use a sensor safe RTV sealant designed for automotive applications, although this won't be any good for the oil cooler cover IMHO.

As said, oil cooler change is a significant amount of work, makes sense to do the job once and use the right sealant.

Kevin
Title: Re: oil cooler
Post by: JamesV6CDX on 21 February 2010, 01:34:43
When I bought my MV6, and took it apart, this is what I found:

(http://i89.photobucket.com/albums/k205/jamesv6cdx/30052009193-1.jpg)

Not sure how co-incidental it was, but shortly after doing the top end job, the engine seized and went BANG big style.

Despite checking the sump before starting etc - I reckon it's this kinda treatment that ultimately killed her  :'(
Title: Re: oil cooler
Post by: biggriffin on 21 February 2010, 15:20:08
 r.t.v.  stands for "room tempreture vulcanastion" meaning it goes off "hardens" hence after a while it starts to leak. silicone sealer stays plyable. yes there are various types of sealents, looking at that photo that looks like a sealent not silicone. ive used silicone for quite a few years and had no problems whilst using it.
Title: Re: oil cooler
Post by: Kevin Wood on 21 February 2010, 20:41:01
Vulcanisation means to form a durable rubber-like substance, not to harden. RTV sets just as flexibly as bathroom sealant but it is properly designed for the environment. It is oil resistant and does not kill lambda sensors like a silicone sealant would.

Look at James' cam  covers. Notice how there is loads of excess sealant around the plug wells but none in the camshaft areas? That's because it has broken down on exposure to oil and is probably what clogged the oil system and caused the engine to throw a rod through the block. So much for saving £5 on a tube of the correct sealant!

RTV is not suitable for the oil cooler cover plate anyway, because we are talking about a metal to metal flange joint with no need for that level of flexibility.

Kevin
Title: Re: oil cooler
Post by: vauxox on 28 February 2010, 19:23:22
iv never liked the idea of lumps of silicone or any other sealant floating around inside an engine and can imagine how easy it is to block an oilway or water way it makes you wonder how many engines have been wrecked over wrong full use of silicone i have lost count of engines i have stripped to find this floating around inside
Title: Re: oil cooler
Post by: dbug on 28 February 2010, 20:49:40
As Kevin says silicone sealant is for baths and gutters not for car engines!!  Use the correct sealant that has been formulated by the manufacturer for that particular application (sealing metal oil cooler plate to metal block).

Kevin is also correct in that vulcanisation does not mean the product hardens - vulcanisation is a chemical process for converting rubber or related polymers  into more durable materials via the addition of sulfur or other equivalent "curatives". These additives modify the polymer by forming crosslinks (bridges) between individual polymer chains.  The vulcanized material is less sticky and has superior mechanical properties.