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Gordon Norris
Prolific User
Username: crewes_missile

Post Number: 144
Registered: 2-2005
Posted on Wednesday, 13 April, 2005 - 20:54:   Edit PostDelete PostView Post/Check IP

Having been blessed with a masochistic tendency of affection for British and Italian cars, the former in particular all having the peculiarly British trait of copious self-lubrication of their undersides with engine oil, I have experienced many a prematurely rotten engine/gearbox/chassis rubber mounting from the effects of oil.

However I have a particular tip/trick which I have used on many a car with great success, (but not on my Bentley as yet) but which should also work on RR/B's, that all but eliminates oil contamination of essential rubbers:

Simply place the part in a ziplock or similar sturdy clear plastic bag before assembly! That's it. Let the mounting screws or studs perforate the bag, but otherwise contamination is all but eliminated and the condition of the mount is still visible through the plastic, or at the worst by undoing the zip/one end. Simple, but it works a treat. Never had a problem with slipping from the plastic, which I anticipated as a possible problem when I first did it many years ago. Simple, cheap, and it works.

A further measure I've used if the part is near a hot manifold, etc is to stick some self adhesive fibreglass backed reflective heat foil (available from most "speed" shops) on the hot side.

Hope this is useful. As noted above, I have not yet done this on an RR/B, but see no reason why not, but usual disclaimers etc apply.

GN.
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Bill Coburn
Grand Master
Username: bill_coburn

Post Number: 383
Registered: 4-2003
Posted on Wednesday, 13 April, 2005 - 23:42:   Edit PostDelete PostView Post/Check IP

Gordon

Without being a smartarse can I suggest a little prevention rather than cure or for that matter prophylactic. Certainly on the SZ cars which I think you favour there are two sources of rotting (and rotten) oil; the weep holes which can demolish the rear mounts and the front timing case which will finish the front mount. The former can be fixed quickly with a little threading and grub screws; the front end however requires pulling most of the front end off the engine and replacing that stupid seal between the upper and lower timing case halves. As this is not the sort thing you do after you get home from work, your idea of protecting the front mount in a plastic bag is great and very advisable. Don't forget though that in the mid eighties there was quite a large batch of faulty rear mounts which simply delaminated. The engine on my Spur actually rotated, shearing both mounts and the only thing that stopped an emulated spit roast was the upper part of the mounts jamming against the lower part's retaining screws!!!
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Richard Treacy
Grand Master
Username: richard_treacy

Post Number: 698
Registered: 4-2003
Posted on Thursday, 14 April, 2005 - 00:17:   Edit PostDelete PostView Post/Check IP

Gordon, Bill,

As a variation on the theme, I shrink-wrapped the new mounts on a friend's impossibly leaky Shadow two years ago, using heavy-gauge plastic. That did the trick too. No more blancmange.

OK, it's just a stop gap, but around a squillion hours' work is required to do a proper repair as Bill has done on that glorious PVI (love the picture of it at Parliament House with the brand new Phantom, although Goodwood must hate it!).

What a job that would have been to do properly: sump, valley cover, rocker covers, transmission, Spirit rear main seal, wheelcase. I did plug three leaky weep holes with silicone RTV though.

RT.
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Gordon Norris
Prolific User
Username: crewes_missile

Post Number: 145
Registered: 2-2005
Posted on Thursday, 14 April, 2005 - 09:10:   Edit PostDelete PostView Post/Check IP

Bill, Richard,

I agree it's best to fix the offending leak. Unfortunately, Brit cars seem to be "born to bleed" and if the slightest oil residue runs anywhere it seems to be straight to a rubber mounting. And even after the offending flow is fixed, sooner or later it will do it again. The bag method has saved me from having to replace many mounts prematurely, and it is amazing how long bonded mounts last when uncontaminated. Luckily my SZ Bentley hasn't developed any leaks (as yet) but I don't have any illusions that it won't!

Bill, your spit-roast-Spur story reminds me: Years ago I saw a Valiant straight six convert itself to a "slant six" in spectacular fashion from sheared mountings..it had triple sidedraft Webers which also suddenly became downdrafts..

GN.
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Richard Treacy
Grand Master
Username: richard_treacy

Post Number: 699
Registered: 4-2003
Posted on Thursday, 14 April, 2005 - 09:23:   Edit PostDelete PostView Post/Check IP

Six Pack R/T Charger no less.

By the way, the engine mounts of a 265 Hemi will fit a Shadow and later SZs with one hole drilled out a little. As Bill mentions, there was a run of SZs with oddball rear mounts and a peculiar but effective and failsafe Metalastic front mount before they changed back to Shadow mounts for the 20,000-series. A Metalastic front engine mount is horribly expensive to replace.

If you throw enough time and money at a Shadow or SZ, you can cure the leaks for good. If you skimp, your friends' oiled driveways will embarrass you whenever you depart.

RT.
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Gordon Norris
Prolific User
Username: crewes_missile

Post Number: 146
Registered: 2-2005
Posted on Thursday, 14 April, 2005 - 09:49:   Edit PostDelete PostView Post/Check IP

Richard,
Maybe that should be one for Larry's list, I would imagine the 265 Hemi mounts were probably common to several US Chryslers also. Maybe the rubber compliance may be a bit off, maybe not. However, see below, there are 2 different grades of mount for RR vs Bentley in the later cars.

Also, with respect to the mounts I note that from MY1989 a new rear mount UR71176 for Bentleys (UR70557 for RR's) replaces the UR19204, and in the Introcar catalogue the relative prices are GBP67.18 ea(new) and GBP21.21 ea(old). What is different about the new one and why 3 times the cost?

GN.
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Richard Treacy
Grand Master
Username: richard_treacy

Post Number: 700
Registered: 4-2003
Posted on Thursday, 14 April, 2005 - 10:08:   Edit PostDelete PostView Post/Check IP

Didn't they mess around with SZ engine mounts indeed ? Rear mounts: first UR19204 (A$40, same part as for a Shadow), then UR23140 ($100) at chassis 3694, then back to UR19204 again at chassis 20,000, then UR71176 ($120) as you state at chassis 23936. Those last ones are now superseded by the UR19204 once again. Was that a visit from Mr C*** Up or what ? As for the front mount (UR19203, $60), the interlude with the Metalastic mount, chassis 3694-16930 at around A$500 each. Hmmn.

RT.
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Patrick Lockyer.
Grand Master
Username: pat_lockyer

Post Number: 403
Registered: 9-2004
Posted on Thursday, 14 April, 2005 - 16:27:   Edit PostDelete PostView Post/Check IP

Food for thought.
How about a mod to stop the oil leaks on ALL the engines a pintle valve is the answer maybe crankcase depression 3psi hmmmmmm.
Don't like sealing up the weep holes that would be another mod if mine leeked badly.
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Bill Coburn
Grand Master
Username: bill_coburn

Post Number: 385
Registered: 4-2003
Posted on Thursday, 14 April, 2005 - 19:29:   Edit PostDelete PostView Post/Check IP

Gordon/
Your slant six story reminds me of a Bentley S sold here in Canberra years ago which and headed for Sydney. The new lady owner coincidentally deceased this last week, pulled in for gas and oil, attendant opens the bonnet and said he didn't know RR went in for slant sixes. Seems the whole engine had fallen over and was still running. The driver did remark that the accelerator seemed a little stiffer!!!