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MG Midget and Sprite Technical - Timing Cover Nut Removal

I have an oil leak which appears to be coming from the bottom of the timing chain cover and have put off sorting until now.

After removal of radiator and oil sump and a block of wood inside the bottom of engine, the straight forward job of removing the nut was started, but it does not want to budge.

Can anyone please confirm if it is the opposite thread to normal and whilst attempting to undo by turning anti clockwise am I actually tightening. There is no mention in the manual or anywhere else that I can see, can someone please confirm.

Thanks
Tim
Tim Lynam

Hi Tim, is it 1500 or 1098/1275 car. Not that it makes much difference. Have you undone the locking tab? It's a normal thread but sometimes is a b***er to remove.

Rob
Rob aka MG Moneypit

Hi Rob, its a 1500, I cannot see any sign of a lock tab?
Tim Lynam

Just checked a 1500 manual and you are right. No locktab. But it's tightened to 150 lb/ft so is really tight. You probably need an extension on anything you use straight from the tool box. Have you a long bar you can add on the end of the wrench or ratchet?

Rob
Rob aka MG Moneypit

If your ratchet handle is 12 inch long you need to put 150 lb force on it at least to undo it. If you make it 2 foot long it drops to 75 lb which is more realistic in the confined space.

Rob
Rob aka MG Moneypit

Cheers Rob, I have tried some pretty basic extensions but nothing strong enough to budge it, but as long as it is loosened anti clockwise I will persevere, 150 lb's is pretty tight!
Tim Lynam

I heard of someone undoing it by having used a spanner on the nut to turn the engine over for timing purposes, forgot to remove it before starting up.
Graeme Williams

Tim, beware of your fingers. I talk from experience when undoing a seatbelt mount. Only press down with the palm, don't wrap your fingers around the bar.

Graeme is right. I seem to remember this trick but was loath to suggest it. I'm pretty sure engine rotation is in the direction that will undo it if you have the ratchet locked against the chassis somewhere. Take the dizzy cap off to make sure it won't start and blip the starter. Make sure the socket is fully engaged if you try this.

Rob
Rob aka MG Moneypit

Graeme, that is a recognised technique, 'though it should be done with the coil LT leads disconnected so the engine doesn't actually start up! The effect of turning the engine on the starter motor should be sufficient to shock the nut loose.
(Edit: Sorry for duplicating advice, Rob)

The usual problem when applying leverage with an extended bar on a spanner or socket is stopping the crank from turning. Putting the car in gear with the handbrake pulled hard on may work, but there may still be too much springiness in holding the crank still. Other methods are to lock the flywheel teeth (large screwdriver or, better a purpose made locking device) Or to drop the sump and use a block of wood to wedge the crank against the crankcase
Guy W

It might not be the timing cover i thought mine was leaking but turned out to be the alloy sealing block behind the timing cover i changed mine for a steel one .Apparently if you put the wrong bolts in it will bend
see picture i think you can tell which one leaked.


mark 1500 on the road Preston Lancs

There is another problem that occurs with that alloy "bridge". The front sump bolts that go into this alloy are supposed to be different to the other sump bolts. They should be shorter, so that they don't break out of the sealed ends of the tapped holes - you can see the domed inner end in Marks photo. If the wrong bolts are used, and if they are overtightened they will break through, strip the threads and allow oil leakage back out. Similarly, it is easy to overtighten the bottom timing chain cover bolts as they go into alloy, unlike the others that go into steel.
Guy W

Thanks for all the tips, I think the spanner jammed against chasis will be last resort, too much of a whimp to try that option, but sounds a great tip!
Tim Lynam

I got mine off with an air wrench came off easy.
mark 1500 on the road Preston Lancs

IMPACT.

You don't need a lot of leverage to loosen it.

Put a T bar on it. Set a length of 2" x 2" wood perpendicular to the end of the T bar, and whack it with a club hammer. -- Anti-clock of course. You don't even need to put the car in gear. Just the inertia of the engine internals will allow you to loosen the nut.

But since you already have the sump off, and wood preventing the crank from rotating, you find it very easy.

If you had the engine on a bench, or if there's enough room to get a good hit without the 2 x 2, then hit the end of the T bar directly with the club hammer. Easy peasy.

I assume the air wrench is an impact wrench Mark?
Lawrence Slater


If there is room, try putting a jack under the end of a tommy bar. You may lift the car, but it should give.

Dave
Dave Barrow

Yes impact wrench I had engine out so easy to get on it i am sure i have seen a gizmo that locks the fly wheel with the starter off
mark 1500 on the road Preston Lancs

Hi I have a similar problem with a very tight nut and my first thought was if it was a LH thread. The engine is out of the car, I have strapped it down to my bench, blocked the crank and used a 4 foot tube over the spanner and still no movement. Any greater leverage and im going to break something. By the looks of the nut it cannot be cut off as its recessed into the pulley and therefore I would have to cut through the pulley to remove it. Before I get to that has any body got any other suggestions on how to move it?

TIA

Trevor
td ayles

Trevor, see Lawrence's advice earlier. The best chance you have is to shock it free. It is much more effective than just using a long lever and regular pressure.
Guy W

yep tried that with a 4lb lump hammer, spanner took off across the workshop :)
td ayles

could you hire a impact driver or take it to a local garage to get it loosened.
mark 1500 on the road Preston Lancs

slogging/flogging spanner and big mallet! if you don't know what one is, it is a spanner designed for being hit!

that little bridging bit is a bugger. tried three times to seal mine and still not 100 percent. don't forget to pack the ends with the wooden packing bits you get in the gasket packs.

previous advice re bolts etc is important. also to note, everything is unf as standard, so the fine threads in the alloy strip easily. it is common to helicoil, either to unf or even better to unc.

cheers
Malcolm
M Le Chevalier

Spanner Trevor? You need a socket, unless you are using a ring. But even then a socket will be better. Use a socket, decent straight T bar, and hit it again. Or as Malc said go and borrow an impact air tool.

Take the block, with the right sized socket to a tyre place, and ask them to undo it for you with their air tools.

But I still say if you hit it right, it'll losen. Maybe some fool put loctite on it. :-.

T bar, extend it with a lever, and whilst pressing down as hard as you can, hit down with the hammer. Pity you aren't closer, I'd do it for you. ;).

Lawrence Slater

not any old socket but a 6-point socket, please!
And that's after soaking with penetrating oil, and using a blowlamp to heat the bolt up.
David Smith

I haven't got any 6 point sockets, just my old 12 point hilkas, bought from Halfords about 40 years or so ago. ;). Never had a problem, but I agree, a 6 point would be better, and a bit of heat/penetrating fluid always helps.
Lawrence Slater

I've broken too many sockets using chatter-guns. Proper impact sockets are well worth the investment IMO.

BTW a bloke I knew offshore about 20 years ago lost an eye to a socket that shattered.

Just sayin'.
Greybeard

When I did this last I borrowed a 3 foot stilson wrench from a mechanical contractor working on the construction site I was on at the time.

Engine was out,so jambed the flywheel and had another person standing on the engine.

richard boobier

Tim

If you're still struggling, I'm due to go to Sheffield on Thursday, or I'll be in Mansfield next Saturday.

I have a long bar or two!

(re-posted from the 'other' thread)
Dave O'Neill 2

Thanks Dave much appreciated, if I do not have it budged by next Saturday a long bar would be a great help and I am only a couple of miles from Mansfield.
Tim Lynam

Just to update you. Got the nut and pulley off, it wasn't pretty. An hour with a disc cutter and I have the need for a new nut and pulley, fortunately I have a pulley. I was rusted solid, I guess from a forward facing recessed nut getting all the water and crud forced into it.

Thanks for all the advise but Im sure there was no way that nut was going to move.

Trevor
td ayles

" -- Im sure there was no way that nut was going to move. "

Possibly ---, if this is the first time it's ever been off.
Lawrence Slater

Trevor presumably you mean bolt not nut, and if you cut the head off how did you extract the remains from the end of the crank? (I may need to do this myself one day soon).
David Smith

Sorry for commenting after the horse has bolted, but I had a similar problem. It just wouldn't shift. I bought an electric impact wrench from Machine Mart for about £45 and it was like magic. Came off immediately. Haven't had to use it since so I guess an expensive option but it was fun!
Graham V

Re. removal of 1500cc crankshaft pulley nut.
Use a chisel and club hammer. It was discussed in 2011:

http://www.mg-cars.net/mg-midget-sprite-technical-bbs/1500-crank-pully-nut-201101221352406646.htm
Andy Hock

Id be curiius how you got the restof it out... that siunds like q mess... i would have gone for a longer bar or taken to a tire shop and had them wring it out
Prop and the Blackhole Midget

After making sure I had a spare pulley and a new cutting disc I got out the angle grinder and made a number of strategic cuts through the crank nut, carefully missing the thread of the crank. After a cut of about 20mm deep I used a chisel to break away the nut and then tried to move the nut with the chisel and hammer. No luck so I made another cut on the other side and followed the same procedure, repeated on each opposite side until the nut moved Unfortunately the cuts had to go down into the pulley. Once removed the rust on the thread could be seen which was obviously the problem.

td ayles

Well done Trevor for your success. But it is still confusing.

Was it a nut or a bolt that you were dealing with? Usually the pully is held with a bolt into the nose of the crank. If that was the case, how did you then remove the remains of the rusted in bolt, having destroyed the head to remove the pulley?
Guy W

I DO use Loctite on our 1380 and for removal use a 1/2" air impact wrench with 1 5/16" AF 6-point deep impact socket, as I have fitted the Minor crank handle nut. A few seconds and the nut is undone.

So far so good! I do need to remove it very soon to replace the timing cover oil seal, so will see if the past performance is any sort of predictor for the next one!

Anyone near Oxford? If you bring the engine to me I can (hopefully) undo it for you.

Richard
Richard Wale

Several weeks in and mines still well and truly stuck, even with the use of extension bars, no room to use a socket so last resort is the purchase of a decent ring spanner.

But my query is, why is the pulley nut tightened so tight, approx 150 lb?

Wish I could wip the engine out and nip to Oxford!
Tim Lynam

Tim,

The correct torque is 70lbf. ft., but even then after a while it is still a job to get it undone.

The engine is out at the moment, but ours is in a Minor, so room to get a socket on the bolt and an extension out under the radiator and through the starting handle hole in the bumper to the impact gun. Cheating really!

Richard
Richard Wale

Hi,

Sorry Richard, 70lb/ft is correct for the A-series, but the Triumph 1500 PE94J is 150lb/ft ie f***ing tight!



Regards Steve
SR Smith 1

Thanks for confirmation, its good to realise when you are not the only one that's struggled with this job.
Tim Lynam

A 230ft/lb air impact hasn't shifted mine..yet, application of heat next.
Kevin Fuller

Kevin,

How much air pressure are you feeding that gun?

Charley
C R Huff

Charley, the compressor is set at 90psi, which is the max specified for the gun, however the compressor can deliver 8bar (116psi) at 200l/min (7cfm). As I have stated in previous posts the car has been the subject of some dubious maintenace,the engine has been replaced by a reputable company but obviously the peripheral components by others, and it is these components which are causing various problems.
Kevin Fuller

Kevin,

Keep in mind that the pressure at the end of the hose is normally less than at the tank, especially while air is being drawn. If it were me, I would not be afraid to run the gun at a higher than specified pressure with the assumption that there is some built in margin. I have run my gun at 150 psi tank pressure, and must admit I never looked to see if it had a published limit.

Charley
C R Huff

Kevin,

Out of curiosity, I just checked my gun. It is also rated at a max pressure of 90psi.

However, I also saw that it is rated at 625 ft lb of torque. It seems that a 230 ft lb gun is on the light side, and not up to the task. Just because the bolt is torqued in at 150 doesn't mean it is going to come back out with 150.

Maybe you can borrow/rent a gun with more beef? I have never seen mine fail to easily pull a crank center bolt.

Charley
C R Huff

'70lb/ft is correct for the A-series, but the Triumph 1500 PE94J is 150lb/ft ie f***ing tight!'

Oops, sorry. If all else fails read the beginning of the post carefully. 150 lbf. ft. is definitely f***ing tight!

Richard
Richard Wale

After purchasing a 46mm ring spanner off Ebay which required a little persuasion to fit on the slightly rounded nut, a good long extension pole on the other end and a good pull on the pole, a crack was heard and the nut was loose, what a relief after several frustrating weeks.
Tim Lynam

This thread was discussed between 17/01/2016 and 13/02/2016

MG Midget and Sprite Technical index

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