MG-Cars.net

Welcome to our resource for MG Car Information.

Recommendations

Parts

MG parts spares and accessories are available for MG T Series (TA, MG TB, MG TC, MG TD, MG TF), Magnette, MGA, Twin cam, MGB, MGBGT, MGC, MGC GT, MG Midget, Sprite and other MG models from British car spares company LBCarCo.

MG Midget and Sprite Technical - Crash, bang, rattle

It was raining so hard on Sunday that I had to put the hood up and noticed how noisy the car is. There was gearbox noise (standard 4 speed), tappet noise (new high lift rockers are on the cards), diff noise and a whole host of rattles and bangs.
How do I quiten it down?
I don't want to do much to the gearbox just yet. I need to change the oil, is tehre anything to add to the oil to quieten it? I have changed the diff oil already, how noisy it acceptable?
And the big question, where do all the rattles and bangs come from?
Any tips on locating them and stopping them?

Thanks

Dave (I hope it doesn't rain again, I can't stand the noise) Brown.
D Brown

Earphones and a high powered stereo might work.
When riding in an enclosed tin can all noise is amplified. Even in an MG.
Sandy
SANDY SANDERS

gearbox noise
- change the oil every three years at least, use good quality oil and you could add someting like SLICK-50 engine treatment as it's engine oil in the standard box, or you could try Molyslip or STP if they're ok with engine oil

engine
- change oil and filter every 6 months or 6,000 miles with good quality oil, again you could try Slick-50 engine treatment if that's what you put in the g/box or STP - adjust tappets as part of a full 12 month/12,000 mile service

diff
- yes change the oil at least every 3 years, and you could add Molyslip or STP you'll need to suck some oil out first now - they all whined even when new (I think)

Rattles and bangs tend to come from things that are loose and/or worn so tightening, lubricating and servicing or replacing - following the servicing requirements in the owners Handbook will help, getting the grease gun out at least every 6 months or 6,000 miles for those pionts that need it (or as required for your model)

stopping them is a process of elimination, one at a time

when you've got rid of them all you'll still be able to hear the tappets, g/box and rear axle (but hopefully now they will be quieter) as the more noise you loose the more you notice what is left

I enjoy a low level of noise, tappets, induction and exhaust, a little g/box and back axle it reminds you your driving a sports car and makes it seem you're going faster, I prefer it to a modern car with the radio or music on :)

if you're able to keep above 40 mph you generally don't need to put the hood up
Nigel Atkins

I wear earplugs for any long journeys. You arrive a lot less tired and without the ringing in your ears for the next hour.
You can put in sound deadening material under the carpets, on the transmission tunnel and under the bonnet (if you have room). Also go around and tighten all the screws and bolts (within reason).
When I first intalled my 5 speed, I could suddenly hear a load terrifying new noises which the rumble from the old 4 speed covered but I don't notice them anymore.
Gary lazarus

It all rather depends on how noisy it ACTUALLY is? I mean, is it just generally noisy - and, as is often quoted in here "a noisy tappet is a happy tappet" - or is it engine about the fall out and gearbox about to blow up sort of noise - and, even then, how do you define it!

If you can't hear it with the hood down, then, it's probably "normal".
rachmacb

<<SLICK-50 engine treatment as it's engine oil in the standard box, or you could try Molyslip or STP>>

No, the synchro cones need a degree of friction to work; these additives will make the synchro very poor and could damage the small synchromesh engagement teeth as a result.

Richard
Richard Wale

Personally, I wouldn't put anything other than a good quality 20w50 mineral oil in the gearbox.
Dave O'Neill 2

I doubt if you'll get much noise reduction from the mechanical bits if any, these designs have a bit of noise expected. Consider adding some sound deadening material inside the cockpit under the carpets. Something that won't trap moisture of course. Something like Dynamat works great and is easy to install and doesn't add much weight. http://www.dynamat.com/products_automotive_introduction.html

Bill Young

<<SLICK-50 engine treatment as it's engine oil in the standard box, or you could try Molyslip or STP>>

No, the synchro cones need a degree of friction to work; these additives will make the synchro very poor and could damage the small synchromesh engagement teeth as a result.

I don't think the additives reduce that much friction, I've used them before on daily classics that have done good annual mileage and a mate put Molyslip I think in his B gearbox must be 20 years ago

perhaps using the Slick-50 gear treatment instead, just thought about sharing the engine bottle if that was bought

Perhaps these things only have a placebo effect but I don't think they harm unsofisticated classics

Whatever, changing the oil is a good idea

And of course how noisey is noisey(?)

Nigel Atkins

I think the most important comment here is the very last one by Nige.

""And of course how noisey is noisey(?)""

Many people come into classic car ownership without previous knowledge and experience

Thus many worry that the brakes are poor simply because they do not have the same feel as a modern car.

The same goes for general running noise. If I take out my Mercedes for an extended run I am cacooned in a very confortable noise free atmosphere. I can have a normal conversation wife any occupants and enjoy the CD player without effort.

Now I then get in my midget or any other of my classic cars and jesus wept! The ambient noise is horrendous. I struggle to hear the CD player and general casual conversation is almost too much effort.

Classic car gearboxes are noisey, tappets and general engine noise is very high not to mention road and wind noise. With very little padding the cockpit is by nature a moisey place. I find with the hood down the mechanical noise disappears and all I can hear is the wind noise.

I personally woul;d not recommend ear plugs otherwise how would you ever know when something was beginning to fail?
Bob Turbo Midget England

New high lift rockers will require a slightly larger clearance than standard rockers so won't drop the noise levels!

Interestingly you'll find that once you get over 100mph everything goes very quiet.
Daniel Thirteen-Twelve

Once again Bob I'm with you why is why I always suggest new or recent owner regularly drive their cars to get use to them

I think I've only had one soft top where you could actually hear the radio or CD on the open road over all the over travel noises and it certainly wouldn't be a Spridget

When many pospective owners test drive classics (and some don't even do that) they have wear rose-tinted eyes and ears (I often do) and the actual ownership comes as surprise that why I always suggest go in as many examples as possible and always some very good examples above the price budget so that they see and hear how a good example should be

That's why I'm happy to take people out mine is not one of the best but is good in the important areas, unless you want a show car, and I will point out the many downsides of the model and my car (even when selling)
Nigel Atkins

How about the following -

A good raincoat and hat ?

Big bore exhaust system ?

Drive faster so all you can hear is wind noise ?

Swap it for an MX5 ?

Sorry only joking but basically they were pretty noisy straight out of the factory and that's part of their charm.

Changing the gearbox and diff oil is always a good start and makes a deal of difference especially if they are only half full to start with. The handbrake mechanism is always good for a rattle from the back. Does anything rattle at idle as they are easy to find.

Adjusting the tappets on worn valve gear is a bit hit and miss as the rockers wear hollows on their faces giving missleading results either do it by feel or grind down a feeler gauge so it is narrower then the top of the valve.

cheers Ben
Ben Brown

I know what Dave's talking about...last weekend we had a cold snap, so I road around with the top up for the first time since last April.

I'd forgotten how noisy the little beast was...I could hear all the mechanical bits whirring, tapping & generally doing doing their jobs!

But I love it, I didn't buy this little car for quiet!

But on the other hand, I plan to install new carpet over the winter and I think I may put some heat/sound insulation under the carpet just for kicks...it really was noisy!

:o)
Dave Rhine ('78 1500)

Dave

Go to a car stero shop and get (dynomat) or its generic cousins... the stuff is pheenominal... its a black square of rubber plastic thats sticky on one side and flows like butter with a heat gun, easy to tool and makes a huge differance.. its about 1/8 inch thick... it looks like a joke, but its worth every penny... I want to say I used 12-15 sheets to line my tub... there 24 inches x 24 inches

just my personal experiance

Prop
Prop

I have identified that one of the biggest rattles was coming from my bonnet. I think the hinge is worn. I have sorted it by fitting the rubber seal used on the rear edge of a Mini bonnet. It has stopped the rattle for about 12.00.
I have also fixed the heater fan so I can now survive in the cold a bit better and keep the top down more (I have also dug out my warm hat, gloves and scarf!).

Thanks for the help.
Dave
D Brown

if your heater fan is anything like mine you only turn it on for the windscreen otherwise it seems to cool the air coming out of the footwell flap, I usually only open the flap in the passenger's footwell for cabin heat or my legs and feet get too hot

I've cleaned my heater matrix twice (don't ask why, long sad story) and if anything it now gives out too much heat (when the top is up especially)

I also last time put in a new uprated fan motor which I think may be slightly noisier than the old one but just as inefective at moving the air

Thinsulate hats are cheap but very effective, a scarf and upturned coat collar is a must to protect from the cold back draft - some days you can go without gloves but start by wearing them as you can take them off if your hands get too warm

Most pepole would be surprised by how many good weather driving days you get in the colder months and some days are excellent better than many summer days

I might keep a count this time just to annoy my mate who's too tight to pay for more than six months road tax on his soft top
Nigel Atkins

Dave, as ben says, check the linkages on the handbrake rods. They use felt washers on the ends which shrink at alarming rate and this results in metal to metal contact, which gives a jingle noise over bumps. Mine drove me mad.

Like the others say, they won't be dead quiet but I think they are missing the point. A lot of the rattles and knocks are probably due to things not been quite right, like the bonnet you mention. All you can do is crawl all over and underneath the car with a critical eye and prybar and check for play in anything. The slightest play can give fairly loud knocks which can reverberate through the bodyshell.

When I changed my (old) ribcase for an (old) Sierra Type 9 the subsequent lack of noise was tremendous. The gearbox noise must have been very bad at all speeds, but then again it was knackered.

The only way to quieten gearbox/diff noise is to get quality reconned units.

I have also put some sound deadening on any largish piece of flat sheet and it worked a treat. It stops them vibrating and contributing to high frequency noises.

Matt
Tarquin

Thanks Prop

That sounds just like what I'm looking for!

:)
Dave Rhine ('78 1500)

Just ordered some felt washers for the hand brake linkage. Now to find a source for the sound proofing Prop talks about.
The Midget is getting quieter by the day.
Is there some guidance on how to check for play in the diff and how to adjust/recondition the diff. I know there has been a lot of threads on this issue but does anyone have everything you need to know in one document?

Dave
D Brown

Good point by Tarquin about things not being quite right

I always recommend full and proper servicing and maintenance so this should cover repairing things that are not fully functioning properly

e.g. I had a handbrake cable fitted last year and ensured that it included replacing all the other associated little bits like new felts, washers, nuts, bolts, grease nipples, adjusters that are often left out (not replacing for the sake of it but it does complete the job)

And of course things like driving the car regularly and often for at least 30 miles (that will hep quieten things a bit if only because you then have to find the sources of the noises to keep the car in good order and make the driving even more enjoyable)

I'd recommend caution about buying recon units of anything I've had many not all have been sucessful (if you're really unlucky the recon unit could be very noisey or even faulty)

I was told recently that putting new parts in with the existing parts of diffs can make them noisey too

The more you quieten things the more you'll notice what is left - if things are working well and properly you'll just have to accept a certain level of noise

Sit in the passenger side and you'll hear different noises

If you can goy out in as many other different Spridgets at meetings, get-to-gethers, and if you can a really good example to hear what the limit reduction actually is

Old (over say 5 years) or certain model of tyres can be really noisey (as well as poor performamce with old tyres)

When the noise fully stops - you've either parked up or broken down :)
Nigel Atkins

Picking up on Gary's ear plug recommendation.. I was on the way back from a Sprint in Wales headed to London (4 hr.s), crusing along. All of a sudden I hear this terrible noise, my heart sinks as I imagine road side repairs on the Motorway or worse being recovered home late, tired and still with a broken car.

Then I realised the problem was simply an ear plug had loosened itself, and the horrible noise I was listening to what was the ordinary sound of the car.

I smiled.. tucked the ear plug back in,and continued on my way.

Hold tigh all you long distance people!

James
James Eastwood

Here's a link to another forum on sound proofing:

http://www.mgexperience.net/phorum/read.php?3,1586726
Dave Rhine ('78 1500)

And keep in mind too that with the hood up, you're basically sitting in a tent with a 60mph wind outside. So there's plenty of noise right there, even without the mechanical contribution!

For example, I drive with my hardtop on through the cooler period of the year, and while noisy, it's a lot quieter than with the soft top.

Here's to winter motoring,

-:G:-
Gryf Ketcherside

This thread was discussed between 05/10/2010 and 31/10/2010

MG Midget and Sprite Technical index

This thread is from the archive. The Live MG Midget and Sprite Technical BBS is active now.