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MG MGB GT V8 Factory Originals Technical - Aluminum Flywheel

I bought an aluminum flywheel several years ago for my Rover 3.5 litre SD1 engine. I have since moved several times. My question is are there any special locking washers, flat washers, or thread locking compound to be used on the bolts?

I don't want to button the gearbox up and lose my flywheel at speed! Any help would be appreciated.

Safety fast,

Mick
Mick Mckelvey

I'd use thread locktight on them as a matter if course. One of the removable thread lockers.
Aluminum expands more than steel when heated.
Also the locktight will electrically insulate the two different metals to a certain extent.
Peter

Mick,

if you want to keep your car for racing only and check the whole mechanic at short intervals, the light alloy flywheel might be an interesting item to fit. For normal road use, i would not go for this risc, as there will be no real benefits from this modification. If a lightened fly wheel is on your list, you can have the steel one lightened but even then it will be a problem to use the advantage in a MGB without a lot of investment to the rear end too.

Ralph
Ralph

one vote for the aluminum flywheel. use the proper fasteners (ARP),thread locker and "go for it". not familiar with the Rover torque & HP but with the light weight of the "B" would see no problems. you need the inertia of a heavy steel flywheel on a heavy car to launch, a lightweight "B" can use the alum. flywheel to advantage since is revs quicker. as for security, thousands+ of alum. flywheels are on the road (I have 1 on the 5.0 Ford conversion) w/o any concerns.
kelly stevenson

Hi Kelly,

I don't think that the ARP people believe in thread lockers like Loctite. They prefer proper torque & bolt stretch.

Carl Floyd


Carl is correct, but instead of thread lockers, a coat of oil or grease is the proper way to torque ARP or Any piece of hardware.


We used to use thread locker and more washers but now use less washers as washers have been proven in some cases to actually cause things to loosen up. Thread locker has its place too, but not on something with exactling torque specs.


Sounds dangerous but manufacturers have been doing this sucessfully for years.


-BMC.
BMC Brian McCullough

I like thread locker, the minimum hold stuff. Mostly from an insulation point of view. The bolt doesn't corrode into the thread and may be easily undone. It also won't come undone unless you have a spanner on it. Grease works well, but will take up dust and oxidize etc. The locktight has a surface that oxygen and dust can't get through easily.
It is however a little extra trouble to apply and not something a production oriented workshop could afford to use.
Peter

Carl, looks like you caught me! ARP torque values are based on their brand (ARP) of Moly Thread Lube or Sealer. infrequently, some users may not read their entire instructions and substitute other thread lube or lockers. these itmes are rather costly for 1 application. guess i should refrain from advising improper use of ARP products, but "do as i do, not as i say" HA!
in most cases, oil is ok, but ARP is very specific about the values and their lube. they have a different set of values for regular oil.
my experience is limited, but i read reasonably well and follow their instuctions. the Teflon sealer prevents coolant leaks in blocks w/o blind holes. 5.0's have these. Thanks again for alerting others to the pitfalls of blindly following everyones suggestions.
SAFETY FASTER!
kelly stevenson

"SAFETY FASTER!"

You betcha, and I have the hat. Thanks to Triple C!
Carl Floyd

Having used loctite and sealants for a long time I do believe they have their place. But if you are going to use brand new premium fasteners (a smart thing to do) then following the instructions to the letter is the way to get consistent results. Otherwise... yes, a thread locker may give an extra margin of safety. But the low strength stuff is for fasteners that get removed often, and doesn't do much. Formal testing that I've done has shown that the red or green high strength loctite is reasonably dependable until you get above boiling point where it begins to soften. By the time you hit 300 degrees it's useless. So for a clutch and pressure plate I think I'd avoid it.

For sealants I have yet to find anything that will beat Permetex's "Right Stuff" except possibly the two part adhesive we stuck antennas onto military aircraft with. It is very tenacious and impervious to fuels and solvents. Makes a great thread sealant, and does a fair job of helping keep the fastener from backing out. It's also great for sticking those little convex mirrors onto your rear view mirror.

Then for getting the rusty bolts apart, Carl showed me one I hadn't seen, PB Blaster. Works pretty good too, although there was one leaf spring center bolt that it would not budge. Still it's about as good of a penetrating oil as I've tried.

Jim
Jim Blackwood

Mick,

coming back to your question, i would not risk to fit a light alloy fly on a street going car. It is not the question how to secure the bolts, what kind of washers or fluids should be used. The danger is in the material itself. Light alloy dos not have the the same module as steel has. What does it help if the centre of the wheel stays on the crank, while the rest is prone to fly around the bellhousinfg due to fatigue of the material?
There are light alloy flys for some production cars, they are tested and designed for safety. BTW, there are very different light alloys used. For a BOP/Rover engine no one has launched a light alloy fly for street use jet, as far as i remember, but i am involved in this for some 25 years only and may be, i did not get all the news in time.

Safety fast!

Ralph
Ralph

The D&D billet steel flywheel can be lightened to 20 lbs without compromising it in any way. If you want to go lighter than that a multi-disc clutch is the best way to do it. Not cheap, but much less than they used to be. But you really don't want to get too light or you'll find yourself slipping the clutch a lot more than you might like. I have a 20 lb flywheel and standard GM pressure plate and it isn't too much weight. I don't think the advantages of the aluminum flywheel would outweigh the easier starts if you're driving it on the street.

Jim
Jim Blackwood

I got one for free when I bought a bunch of BOP stuff from a machine shop, NOS Schiefer brand. Works fine on the street, zips through the RPM range easily. I do need to use the clutch and gas more to get it going from a stop but after that, its great.

Jake Voelckers

I have one of the aluminum flywheels (from D&D), so I speak from 1st hand experience on this. It was something like 9 or 10 pounds, much lighter than a steel would could be. I like the way it is. The engines revs quickly and it has nice driveability. No, I don't slip the clutch (you don't have to), and I am not worried about it being partially aluminum. If you look at the ones available, they all have a steel insert that the disc contacts. A place like D&D or VB or Moss (regardless of the engine they go on, the flywheels are all made by the same place) would not be selling them if there were problems. The liability risk would stop them. I would assume that the older one you have is still probably made by the same group of people.

I bought new grade 8 socket head bolts and torqued them to whatever the manual said. Believe me, they are not coming loose. I think they have the highest torque settings in the assembly of the engine. I did not use any loctite, my machinist said not to and as he does it for a living, I tend to trust him on it. One thing these flywheels do not have is locating dowels for the pressure plate. you might have a machine shop put some in BEFORE you find that out yourself.


Don't let people that don't have one talk you out of using it.
Richard Morris

I am very fortunate to be very close to ARP about 7 miles. I have attended some of their tech sessions, as per Carl, they really emphasize on using their lubes and their torque method. I use a set of rod bolts that had to be measured before, then torque and measured again, then install in the engine. this provided the correct torque.

As for alum flywheel do your self a favor and use a grade 8 washer with each bolt, this increases the loading and makes the installation stronger.

Alum flywheels when they do come apart is at the center were the bolts are, thus using a grade 8 wahser increases the strengh in the weak area.

Bill Guzman

thanks Bill for the update on ARP Fasteners & their requirements. as i noted above, their thread compounds are $10 or less per tube. there is enough to have several application left over for future use. My flywheel is a Ram brand with a replaceable steel facing. should the facing be scored, Ram will replace it with a new facing for a fee Plus S&H. The steel F/W will need replacement if scored too deep. the billet flywheel seems no more likely to explode than a steel one. the Key is QUALITY!
SAFETY FASTER
kelly stevenson

This thread was discussed between 19/10/2007 and 24/10/2007

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