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MG MGB Technical - Oil Additives??

Hi folks......Just a quick thoughts on oil additives to an 1972 MGB GT. Mostly engine, Gearbox/Overdrive and rear axle. I have used the good old "STP" in older vehicles before but i am asking if anyone has used it on there 1798cc but the service sheets say do not use any anti-friction additives in the gearbox and rear axle.
So what are your views?
Mark

Why do you need additives? modern oil is more than adequate, spend the money on something usefull like beer or shiny bits
Ron
R. Algie

Mark

http://www.chris-longhurst.com/carbibles/index.html?menu.html&engineoil_bible.html

Paul
Paul Wiley

Excellent info Paul
R. Algie

Additives in old engines/gearboxes can be useful in covering-up things, but can actually accelerate further wear. When you add something like a 'viscosity improver' you may well see a higher oil pressure on the gauge, but that is only because the flow through the engine had been reduced. Since the OD works by friction using an anti-friction additive is somewhat counter-productive.
Paul Hunt

Mark-
Oil additives were a good thing when they came on the market way back in the old days when straight-weight oils were the rule and multiweight oils were viewed with suspicion. However, today's modern oils are so much more advanced that I can see no circumstances where any of the commercially available additives would add any worthwhile advantage. Spend your money instead on quality oil (Mobil 1 is great stuff) and a fine-straining quality oil filter [Mann (Part# W917), Purolator Pure One (Part# PL20081), AC Delco (Part# PF13C), Motorcraft (Part# FL300), or K&N Performance Gold Oil Filter (K&N Part# HP2004)] and change them both often. Your engine will thank you with many, many miles of reliable service.
Steve S.

Is Castrol still not the oil of choice, I have used it with no apparent problems?
SC
Steve C.

Steve-
Castrol GTX is the best petroleum-based oil there is. It would be hard to go wrong with it.
Steve S.

Synthetics may not be best choice in all circumstances.
Oil Filter Review
http://www.ntpog.org/reviews/filters/filters.shtml
From Martins article

When switching to a fully synthetic on an older engine, or one with a higher mileage, it is the ester that can cause problems when one changes from mineral to synthetic. Ester base oil used alongside PAO base oil in lubricant formulation has excellent natural detergency. In other words, it will clean up deposits on component surfaces as a result of thermal and oxidative degradation of the lubricant. When one switches from typical mineral-based engine oils to a typical synthetic-based oil, the varnish layer will be removed by the ester in the synthetic oil and become suspended.


This suspended material can rapidly clog filters and can block oil flow passageways and lead to component starvation. The same is true for gearboxes and other industrial machines. So think twice about switching to synthetic oils in applications where the engine or other machine has been operating for some time with mineral oils.



On rebuilt engines of the older type, such as MGB, the same applies, allow for bedding with a standard oil, and then switch to a synthetic, although there is some concern that the higher detergency will not allow a beneficial depositing and as such, the oil consumption may prove a problem.

http://www.xpowerforums.com/Motor_Oil_FA_Questions.htm

Paul

Paul Wiley

Hiya folks thanks for your comments, im a bit suprised to see you using fully synthetic oils instead of mutigrade 20/50w. Surely a mutigrade would be more effective on an older engine such as you beloved MGB GT, but if an synthetic was used what viscosity have you used in the past bearing in mind im located in the highland of Scotland United Kingdom "where the cold weather does always stay"
Many thanks too you all....Thanks
Mark

Mark

I recommend you follow the links.

Synthetics offer better protection than mineral oils, but on a high mileage engine with previously exclusive mineral oil use, they can be *too* good!

A change to synthetic should be done around 5,000 -10,000 miles after a full engine rebuild as i understand it. Doing it at a greater interval to this, could cause problems. The detergents present in modern synthetics could start stripping miles of crud from internal oilways of the engine. Whilst this could be considered a good thing, it only needs one of these bits to block an oil passage and you can imagine what may occur.

The xpowerforums link is a very good one to start with.

~PHIL
Phil

I have used conventional GTX for years, but since it changed from 15W/50 to 15W/40 in the UK I'm just not as happy with it in the V8 particularly. There is also a GTX Magnatec synthetic of the same grade but only being in 4 litre packs instead of 5 litre, and the high price anyway, just doesn't make it worth it in my view. I've gone the other way - to Halfords 15W/50 for both the V8 and the roadster. There are several grades of Mobil 1, for example, available from 0W/20 up to 15W/50 and the lower viscosities are definitely unsuitable for an engine the age of the MGB in UK temperatures. The 15W/50 would be fine, but at 37 quid for an oil change - plus VAT! - it just isn't worth it. Something recommended for motorsport and turbo use at high revs is just too good for engines of my age, mileage, and usage.
Paul Hunt

The only effective oil additive I have ever encountered was when an acquaintance stuffed the noisey gearbox in his Jag XK 120 with a combination of sawdust and whole bananas. Don't ask where the inspiration for this mess came from, but, incredibly, it did quiet his gearbox long enough for him to sell it. True story.

I once rebuilt a Plymouth V-8 which had been religiously cared for with STP at every oil change by its proud owner. When I got it to rebuild, the interior surfaces seemed to have been dipped in chocolate, and it took several DAYS in the hot tank to etch that crud off. The coating? The protective power of the racer's edge - STP!

Altho there might be some aftermarket additive of some value somewhere, I have yet to find one. Most modern oils seem to have all they need, and tested on fleets of engines other than my own.
Bob Muenchausen

Bob, I once did a chevy motor that had the oil changed every 3000 miles, belonged to a Lifesaving Crew. They used Quaker State and I had to use a putty knife to remove the build-up. However, I really think that most oils are very good now days due to competition and maybe a boost from NASCAR. Paul, if you need some "good ol" (The Bubba Comin Out In Me) 20W50, let me know and I will throw some in a box and send it to you.

THANKS AND MERRY CHRISTMAS TO ALL AND MAY GOD BE WITH YOU AND YOUR FAMILYS DURING THE HOLIDAY SEASON AND MAY THE COPS STAY OFF YOUR BUTTS UNLESS YOUR DRINKING...
Steve C.
Steve C.

Steve C

Oil analysis of GTX after nearly 9500miles, still in reasonable condition, so with regular changes its still a very good oil

Iron=12
Chromium=2
Lead=8
Copper=13
Tin=0
Aluminum=6
Nickel=0
Silver=0
Silicon=11
Boron=2
Sodium=11
Magnesium=64
Calcium=1908
Barium=0
Phosphorus=1145
Zinc=1304
Moly=40
Titanium=0
Vanadium=0
Potassium=0

Fuel <1
Water NONE
Soot/Solids NONE
Glycol NONE

Visc100=13.07
Oxid=47.0
Nitr=41.0
TBN=2.41
Paul Wiley

I'm using the new GTX 15/40 in both my MGB & TR6 and don't see any differance in pressure, although both engines are low mileage
Ron
R. Algie

Steve C.
Re your comment about the lifesaving crew's Chevy with 3000 mile oil change interval and heavy crud buildup. I serve as engineer for an ambulance squad and it's not unusual for emergency vehicles to spend long periods, sometimes hours, at idle or fast idle. Use on these engines is better measured in engine hours rather than miles. Our ambulances have engine hour meters and we do service every 3000 miles or 150 hours, which ever comes first.
Bill
Bill Boorse

Another good link regarding oil additives:

http://www.vtr.org/maintain/oil-additives.html

This one pretty much debunks the benefits of PTFE (Teflon) in automobile engines. If PTFE is so great, why won't DuPont allow the additive makers to use the name? Because DuPont knows that Teflon is not useful in an engine.
Paul Noble

Bill, in defence of Quaker State, I did think at the time that it may be due to the idling time but I have been told of many stories about QS but this has been some time ago. It may be OK now but I will stick with GTX.
Steve C.

When I was a gunsmith, I made replacement solder-in chokes for shortened shotgun barrels. The choke tubes were made from steel tubes, extruded through a die with a mandrel. We had problems with lubricating the tubes so that we got a slick finish and not stick in the die. After trying lots of lubes, we found that 50/50 STP/engine oil was the best lube to use. Far better than any oil alone. From this expierence I have to say that STP and it's lubricating qaulities could have some merit in an engine. I have also used it for years in other veheciles and found it to raise oil pressure faster on an engine that has been at rest for a while. Seems like the oil/stp stays in the bearings longer than oil alone
gerry masterman

Gerry,
I think that STP probably had its uses, but my guess is that it was probably in race cars with frequent oil changes, frequent tear downs, and extreme requirements at a time when many off the shelf oils needed a boost under those conditions. Modern oils seem to be a lot like modern engines ~ closer to their racing forebears than older production engines/oils were.
Bob Muenchausen

G/Day every one and a happy X/mas. My experience with STP has not given me any faith in it for road use. Its ok for racing clearances but NO GOOD for road. If an engine has tight clearances it can and will break oil pump drives (thick oil, not much flow to bearings)I have been in the motor game a long time and would not use it in a road motor.

Denis
denis hill

STP(strained tiger pi##)has been around as long as bad oil ouzed from the ground. We now have some pretty sophisicated oils from which to choose.All of which will be compromised I think with the addition of additives.
I have been using Castrol Synthetic(really a semi-synthetic)5W50 for the last 150k.The engine was rebuilt at 90k,and started with the synthetic at 115k.
The '5' in the 5w50 works very well in eliminating dry start-up and the '50' works well when warmed up.At 255k I had to replace the cam and lifters. The lifters were the culprits and wore down the cam lobes. The damage actually wasn't that bad considering the milage,but since this car is a daily driver (except during the silly season,no comments from the tropics)I considered this operation as maintenance.
Cheers and a happy and a merry to all.
Jon
Jon Rosenthall

Marvel Mystery Oil can help if used properly when needed.

I've seen some caked up engines too - almost looked like fresh asphalt inside. I think the major contributor to that is a regimen of short trips which don't allow the oil to heat up to operating temperature.

GM Engine Top Cleaner is also good when used as directed, although it's not really an additive.
Glenn Kendall

Hi all.

I am confident that PTFE coating of bearings is an effective way of reducing friction when properly applied to bearings before assembly. The application process is not simple, and it may not be appropriate for all bearings.

I have used PTFE additives on various vehicles, and found that it would appear to quieten a whining gearbox and aid gear engagement.
I have also observed that the tickover speed of a treated (carburated) engine tended to rise after a PTFE additive had been applied. (an engine with engine management will not show this). The beneficial effects appear to happen gradually, not immediately.
These improvements may, of course, simply have been the result of 'bedding in' or some other factor.
I haven't noticed a fuel economy improvement.

I have also observed thin flakes of hard black material (often curved, as if from a bearing surface) in oil drained from vehicles that were treated some tens of thousands of miles before. I have wondered if these flakes could block oilways.

Don
Don

Don,

The trouble with PTFE as a coating for bearings is that it is not very tough. After all, you must not use steel utensils on a Teflon-coated frying pan. It scratches very easily. I also don't know how compressible the stuff is. Since it is so soft and scratchable, I suspect that it would deform and allow sloppy tolerances under the heavy loads put on bearings.

The most telling reasons (to me, at least) against the use of PTFE in motor oil are that it does not dissolve in motor oil; it remains in a particulate state. As such, it could build up and clog a filter or small oil passage.

Secondly, while I'm not expert, the experts at DuPont, the company that makes PTFE and holds the patent on it and the trademark name Teflon, do believe that PTFE has no value in an automotive application. That's why the additive makers can't say that they have Teflon in their product. DuPont may be required to sell them the PTFE, but they are not required to allow the use of the Teflon name. If there were a good use for it, DuPont would be marketing their own products or engaging in a joint venture with a major oil company. If Teflon is so good for an engine, at least one of the major motor oil companies would have a premium brand that included it. AFAIK, no motor oil is available with PTFE in it, only the snake-oil additives are. DuPont is the only source for PTFE and they believe that it has no use whatsoever in an automotive engine. They didn't get to be one of the largest companies in the world, by passing up business opportunities.
Paul Noble

I have used Lucas oil stabilizer in an old Bronco. Seems to work well. Actually stopped engine oil leak. Never used it in my MG's. Anyone have any experience with Lucas?
Dan H.
Dan Hanson

Don't they have something to do with MG electrics? I'm only guessing ...
Paul Hunt

This thread was discussed between 21/12/2003 and 30/12/2003

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