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MG Midget and Sprite Technical - 1275 engine vibration

Hi. After now completing the midget engine rebuild, which was my first, I had clutch problems. I was not feeling well enough to have the engine out again so I paid a mechanic who does work for our local club to fix it. He put a better quality pressure plate in and replaced the starter ring. The engine now vibrates at stand still in neutral. You can feel it through the body and the steering wheel. The changes I have made which might contribute in addition to above are new engine mounts, new exhaust manifold and front retaining bracket, Replaced missing gearbox mount on one side. Any ideas as this could be time consuming. Thanks in anticipation
Walter
W Clough

I'd start by having a look around all the likely areas for something on the engine/gearbox touching the body. The engine/gearbox mounts should isolate any vibrations from the body so if something is out of line or incorrectly fitted you could get some strange noises or vibes.

Try looking at the exhaust brackets near the gearbox as they could have been bolted to the body by mistake. Also the clutch slave cylinder is quite close to the chassis and may touch if something isn't lined up properly.
john payne

If John's checks don't find a fault I'd pull the starter motor and look at the ring gear and rotate the engine to make sure it is properly seated on the flywheel.
David Billington

have you had it back to the mechanic for a look...thats where id start 1st

But id bet its an attachment of some type

Is the vibration contant, or worse with faster or slower rpm, does it do it only at idel out of gear, or does it only do it when the wheels are rolling in gear

When is it most noticeable and can you replicate the vibration at will under certian conditions

Vibrations can be tricky....there hard to cover up with just a loud radio

Prop
Prop and the Blackhole Midget

"...and rotate the engine to make sure it is properly seated on the flywheel"

Also check that the flywheel is correctly attached to the crank.
Dave O'Neill2

Many thanks guys for help with these ideas. It will be a while before I can check all this out as I am not good at the moment. I hope it isn't the starter ring or flywheel or I'll have to revert to the club mechanic. I'll let you know when I know more or when it's fixed. Cheers
W Clough

As I had fitted a new LCB manifold I thought it might be touching the body once started up. I made a small half moon gap in the body flange around where the manifold goes through. I was unlucky. No improvement. The mechanic who renewed the clutch came to see it today and the vibration is worsening. He confirmed that the vibration is from within the engine. Sadly he said it could be the crank and that it was nothing to do with what either of us had done. I will have to wait a month till he can take it in but this is going to a large bill I would think. I will keep you informed.
W Clough

Wow... how lucky and conveniante for the mechanic that its your engine you built and had nothing to do with his work...that man certianly dodge a bullet...plus he gets to charge you to fix it,

Curious did you notice if he was laughing as he drove away


Prop

Prop and the Blackhole Midget

Can you post a video on you tube so we can see and hear the vibration.

Prop
Prop and the Blackhole Midget

Have you checked the state of tune? You will get vibration if it is not set up properly. You could also check that the flywheel is on ok by removing the starter and turning the engine by hand.
HALL JOHN

That idiot still grips my nuts, I thought about that several times today

It ran fine after the rebuild, then needed a clutch, so this idiot does the work, and whamo theres an engine vibration...

And just like that, oh no its not anything ive done, its got to be the crankshaft, sure tow it on down and ill rebuild it for you...GEZ.

I used to be an optimist, then I turned 12 years old

I still think the flywheel isnt mounted correctly (upside down or not flush) or the ring gear isnt seated well

But its just the idea of this idiot saying yepp its the crank shaft, no doulbt about it

What do you bet this idiot takes the car in fixes his Boo Boo, and never touches the crankshaft and charges Mr. W out the yen yang

Its idiots like him that just make me sick

Prop
Prop and the Blackhole Midget

sounds to me like the Mechanic has not tightened up something and now its loose causing the vibration. . i would get him to check his work first of before giving the car back to him to re-solve. . .
P Bentley

I would take a look at the new engine mounts first before pulling the engine, when I replaced my clutch I also fitted new engine mounts the car felt like a tight drum when I started her and the whole car shook badly, I re-fitted the old engine mounts and it just purred, got a refund for the engine mounts, I'm not going to say where I got them because they were clearly embarrassed and responded well to my complaint,
just my two bobs worth,
Dave.
Dave Warren

""just my two bobs worth""

:-)

I like that, im using that the next oppertunity comes about

Prop
Prop and the Blackhole Midget

Hi guys. I'm back. I phoned the club mechanic after he did not come back to me and he says he now has a full time job and can't help. He did say that if I subsequently found that the problem was to do with anything he had done he would pay up but was confident it would not be that way. I have finally found a chap in Stockton who used to work for Ron Harper tuning. He says that if I had not told him the recent history he would start by checking the tuning. (Good comment from John Hall). He put the car on his machine and reset carb, timing, tappets and said I had used rubbish plugs (Unipart bought at autojumble). He changed them for NGK. Well it is a lot better withe engine not having to come out and this 40 years of experience classic car mechanic and night school teacher in motor mechanics said he would not have thought anything wrong now if he had just seen the car. I drove home at an indicated 70 on the bypass with the odd spurt to 80 on dial (actual 70. I still think it vibrates more than it did originally but I am going to live with it a bit and see what happens. Maybe I'm getting too old. All the best to all of you out there
Walter
W Clough

Walter,
those spark plugs show what can happen with fitting "cheap" parts (cheap usually ends up being expensive) what other parts (other than engine) have you fitted particularly modern made new parts

it might be that if you use the car regularly on reasonable length journeys and fully run the engine in things improve (they don't usually with lack of or little use)

the regular use on reasonable length journeys should also help you find if the vibrations get worse or perhaps isolate the area they originate from

if the clutch is to blame perhaps with use it might wear in, as you don't want the engine out again and I certainly don't blame you why not enjoy the car as it is and see if it get better, if it gets worse then at least the problem will be more highlited
Nigel Atkins

Thanks for your sensible comments Nigel. You get some stick on the site, all good natured I'm sure, but I appreciate your constant input and as you say some one may be new to the site and not be aware of your earlier input. I'll give the midget a good blast now through the summer and hope to regain my previous confidence as it is now a very pretty car
W Clough

"... as it is now a very pretty car"

Any pics? We love pics!
Dave O'Neill 2

I'll post some pics as requested once thread reactivated
W Clough

Why am I having trouble loading images? I'll try again with one

W Clough

Wow - that's CLEAN.

Put a K-series in it....
L McInally

Walter,
totally wild shot, if you have electronic ignition have you checked the delicate wire aren't chaffing inside or outside the dissy cap or trap under the cap rim - but I'd have thought that would cause intermittent problems throughout the rev range or suddenly cut the car out

is it just my eyes or is your carb heat shield very small, if so this might cause problems when you have the car running when it's hot

that engine bays far too clean, good for working in but we need to get you getting it dirty with use
Nigel Atkins

Im wondering if your carb is to big... that looks like it could be a SU... HS / HIF 6 or even 8 by the looks of that dash pot

It could be getting to much raw fuel and not enough fuel charge volocity to atomise the fuel

How did you go about metering the fuel needle for the carb thur out the rev range...

Maybe you just need a day with peter burguss on his rolling road to get the carb and dissy tuned in properly... just dont let him cut your hair of do a heart transplant on you...hahaha

Id seriously consider downsizing the carb to a SU HS 4 unless your strocked out to a 1380 to 1460

Prop
Prop and the Blackhole Midget

Prop, the carb is an MG Metro HIF44 which a well known conversion especially on your side of the water. In fact it was off this site that I got the idea. Also spoke to a guy at a show who had done the conversion. They are 1 3/4". They suit the engine well giving more torque and better mpg but apparently no more bhp. It picks up really well and is easy to adjust. I got a remanufactured one set up for a 1275. You have to fit a lower angled manifold or they foul the bonnet
W Clough

Yes but what engine do you have

The engine you show does not appear to be a standard A series 1275...appears to be more of a variant

Prop
Prop and the Blackhole Midget

Standard 1275 out of a Sprite, So I was told
W Clough

Prop - which bit of the engine doesn't look std 1275 to you ?

We've covered the carb - its a single HIF44. And there's a LCB exhaust manifold.
Dean Smith ('73 RWA)

If you go to C. Other thread about exhaust bracket it shows the other side of the block... it appears to be what I think is called an "intla" ..

It appears the oil filter is at the top of the block on cly #3. Is the give away that somethings not right

If it is an "itlna" agian thats the wrong spelling then that would be a huge take away as to why there is vibration, because the crank shaft at the flywheel mounting and the flywheel its self has to under go some radical to the point of extreme modification to force it to fit... im only aware of this being done 3 times....and do not know many details and will never see one of these in my life time

Im not sure where C. Stands in this discussion, he may not truely know, or he is a freaken troll wastening our time, he clearly has insight and is accomplished in spridgets and the 1275, so he should know something is not like the rest, but this 1275 variant isnt all that common

So at this point im keeping my fangs in check and my claws retracted till this plays out... old age has its rewards I guess

Prop


Prop and the Blackhole Midget

If C is me Prop then please be aware that I have been called worse over the years but still unacceptable. As to wasting time then every time we members ask questions it is taking up someone's time if they respond. The guy that put the engine in over 20 years ago bought it from the Welsh MG Centre as a used AH Sprite 1275. As to this vibration problem, it has only manifested itself since the flywheel, clutch etc was out during the last engine removal due to clutch failure. Prior to that it was smooth. You have told me before Prop that the problem was probably with the bloke who did this work for me. I can't prove it unless the engine comes out again. I have been using the car as Nigel said just to see how it goes and it will either get better or worse which would identify the problem. I have been doing this but it has taken a lot of the pleasure out of using it. I may get the engine taken out again. I have spoken to the bloke who put the engine in 20 years ago and he has suggested that as the engine came out minus gearbox last time the clutch may have been caught when the engine was being refitted. I will keep you informed but it may be a while
W Clough

Prop - you're are just wrong on this one. Please stop.

It is not a Marina or Ital block. The Oil filter is in the normal place, its just the additional alloy housing is not bolted on - a black lifting eye is on there (temporarily).

Even if it were an Ital block (and its not)....There is no secret to getting it running and no reason to induce vibration. The only modification required is to machine the flywheel to fit the end of the crank (or vice versa). Its been done any number of times by many people (including me) on this BBS alone.

The only troll wasting peoples time on this one...is you.

"W Clough"...Please just ignore Prop. Its a useful rule of thumb on many many threads.

Dean Smith ('73 RWA)

Bang on Dean. Thanks. Here is another image just for interest

W Clough

I stand corrected...things just looked odd and unconfirmed

Im glad I left the knives in the drawer

Prop
Prop and the Blackhole Midget

Walter,
Kenlowe fan or at least thermoswitch too

not that I know anything about it but I can follow the idea of perhaps possibly having clutch/flywheel from just taking out and putting back in the engine

I know how you feel when the car isn't running as it should, I've had lots of experience of it, but stick with it as when it better you'll soon be back to enjoying the car

keep using it as it might wear-in and slowly fade away or it might wear out and you'll know for certain what it is

do keep checking all your levels such as engine oil, gearbox oil, clutch fluid and changes when required time based if not mileage

I've just changed my diff oil again as someone put that they changed their's every year and the diff whine went away (or below noticeable from previously) as I use fully synthetic diff oil I thought I'd leave mine to every two years and I must say the whine seems much less but I've yet to test it with the roof up on a stretch of boring motorway or dual-carriage way at 70mph - and it might be just a placebo effect I'll have to wait and see

my point is that sometimes it's a matter of time (and regular thorough fluid changes on some issues) so don't wish away your time and carry on using the car as much as you can, the odd journey now and again means it may take longer than (when you can) regular reasonable length journeys

or of course there's the hill-billy sh*t or bust method a few good burn-outs with slipping the clutch :)
Nigel Atkins

I thought I'd bring you up to date with the latest on the engine vibration after many months. Due to health problems I was not able to take the engine out again myself so let a garage do it who work with older cars. The first thing was to get the flywheel and clutch balanced. The engine was thought to be ok so that was not dismantled again. The balancers found a crank and checked that first. Then they put the flywhhel on and had to make the tiniest of drill holes to get perfect. Then a brand new clutch(yet another after only a few miles. I thought I'd play safe as the engine was coming out agin)was assembled to the flywheel. This was a genuine Borg and Beck. I couldn't believe the amount of material that had to be taken off. The professional balancers said that this was quite normal. I have attached a photo. What an inditement against B&B. The car seems to be much better but I am surprised that I have had to do this. Maybe I was being a bit demanding. Welsh MG said I was being "anal". I was not sure what this meant but it didn't sound nice but I am proud to have high standards. I just need to get all the road sdalt off it now from its return trip.
W Clough

Whatever happened to the old adage "the customer is always right"? I can't understand any business saying the customer was being "anal". I mean, he gave his professional advice but you, quite rightly, have your own standards, and was willing to back your standards with money.

Anyway, your engine could have been a Monday morning engine, made of bits rejected from the previous week, where all the bits conspire to make a rough running engine.

Having a B&B clutch so far out of balance is also a surprise to me. Maybe it was a new B&B rather than a NOS B&B.

Rob
Rob aka MG Moneypit

The clutch was a New B&B but even so you would have thought they could have made them more concentrically balanced than the one shown in the photo
W Clough

The NOS B&B covers hardly needed anything doing to them. I fitted a new one recently and nothing was required to rebalance the crank. The current 'B&B' parts come from a distribution warehouse near Oxford and are made abroad. So much for quality control!
Bob Beaumont

Good call WC
So if this new p/plate had been fitted up as normal relying on manufacturer's balancing you would have still been vibrating - Fairly poor quality control on someone's behalf really
Can't believe how far out the thing was
Congrats for getting it sorted out
willy
William Revit

I have to agree with report of the poor attitude of the Welsh MG Centre. Years ago I bought five chrome wire wheels for a B and he sent four and a fifth painted one. When I pointed out that wasn't what was ordered he was really unpleasant. Also with the wheels I ordered a used WW bag axle, which got lost by the carrier for three weeks. He wasn't at all helpful about trying to chase them. It's a pity because he would be a good source for used parts if he wasn't so difficult an unreliable. Its a good job we have Andy Jennings as an alternative, even if his parts are sometimes ropey bordering on scrap!

dominic clancy

I would have thought that sending that image to Borg & Beck for a comment might be worthwhile as that is an appalling out of balance.

I balanced a 12" diameter 3/4" thick steel disc recently and that was about 4g out which would be about 2 or 2 1/2 of those holes ,judging from the picture, and that had noticeable vibration, especially when running at critical speeds, and it only ran upto 1250RPM.
David Billington

I bought the clutch from Northern Components who asked if I could let them know the outcome. They know the people at B&B and visit them regularly apparently. I phone Northern this morning and attached the photo. I'll report if I hear anything
W Clough

I've never seen that much metal needing to be removed from a clutch cover before to get it to balance.
Daniel Stapleton

Jesus, are you kidding me... 17 - 3/8 inch diameter holes, what is that 8 ounces of steel rmoved, and you plan to rev this thing up to what RPM ? No that is not normal, ive never heard of anyone removing that much metal because the ( clutch ) is out of balance

Buddy NO ! NOT! Nit !

You do realize when that thing explodes at 5000 rpm, it wont be contained to just in side the bell houseing... exactly how close is your knee caps to the bell housing

If your ( fill in the blank....) enough to risk your own knee and leg amputaions, thats fine, But you do not have the right to ever risk a passanges legs and body, im telling you flat out, you must inform any and all passangers of the risk there taking while in this car when the engine is spinning

17 huge freaking holes located on one corner in the clutch is NOT the defination of ANAL, maybe ASS, but NOT anal.

FAIL, PERIOD !

Pull it agian, and fix it right

Prop



Sorry, but I have to ask the obvious

Why not just return it, and go with a differant brand...(hazel qualingine ???) Something like that



Prop and the Blackhole Midget

WC,

I'm going to have to go with Prop on this one. I wouldn't want to put that swiss cheese pressure plate in my car. I think they need to give you another one, pay for balancing the reject, and pay to balance the replacement.

Charley
C R Huff

I had to smile at Props comments as always. and CR Huff is right that I should have all paid and everything made OK but I have now a balanced engine. I am pleased with what I have but agree that the inputs have been crap. Welcome to the real world.
W Clough

C.

That was impolite of me above, I should have posted nicer... im a little on edge with cabin fever

But really ... im sure the car does drive better, but I have to stand on my primis, im not an engineer, but this set up scares me

The damage to both car and humans will be extensive when this thing detonates....I know its a freaken night mare your dealing with, but sometimes your stuck having sex with a fat woman

I really think you need to make plans to correct this, sooner then later... im not joking about leg amputations


Prop
Prop and the Blackhole Midget

Your call WC, but when you look at that pressure plate to imagine the stresses, don't just think about the stress from rotation. Remember that when you step on the clutch, the spring load is taken by the perimeter of the cover plate, which has been drilled full of holes.

The drilled arc takes up nearly 1/4 of the circumference, and for that part of the circumference there is significantly less than half of the original metal. I find it difficult to believe that the shop that did the balancing was willing to release the part, and I find it hard to believe that any shop would install it.

Charley
C R Huff

I haven't been following this tale, but from a quick catch up scan I think you have had it out of balance with two different clutch assemblies, which does seem a bit odd. And to have to drill that much out of the second one to get it to balance seems extraordinary!

I know that you have had the crank itself balanced, but does your engine also have the correct harmonic balancer on the front of the crank? Was the crank balanced with this fitted?
Guy W

Hi Guy. The flywheel and clutch were balanced with a crank provided by the balancing company
W Clough

When they did mine, some years ago, the crank, flywheel AND harmonic damper all needed to be balanced together as a unit.

If the flywheel and clutch have been balanced, does this explain the amount of metal taken from the clutch cover - possibly in an attempt to balance the much heavier flywheel, which itself should have been balanced together with its harmonic balancer.
Guy W

I can quite understand Walter not wanting to dismantle his engine again so he could get everything balanced together, which would have been the ideal. But the garage did the next best thing in providing a crank which they balanced on it's own, then fitted the fly wheel and balanced the two then fitted the clutch and finally balanced all 3. I think the New B&B clutch must be the ultimate culprit. I would certainly get in touch with them with pictures and ask them how safe, in their opinion, the clutch is after having all that metal taken off. If they still employ engineers (instead of just buyers) they may have something to say to their suppliers.

Rob
Rob aka MG Moneypit

The photo of the clutch cover seems to have disappeared.

Can anyone else still see it?
Dave O'Neill 2

Dave
It appears not to appear ---- gone
willy
William Revit

It would appear that WC took his toys and went home

Very odd

Prop
Prop and the Blackhole Midget

Prop are we not allowed to sleep or work? Walter was last here at 8pm last night!
David Smith

I had an uncomfortable telephone conversation with the supplier who I promised to provide feedback to. There was an implied threat of potential legal action. Being a coward where my savings are concerned I removed the image as he had suggested. What a world
W Clough

Vibrations after a clutch change are often because the incorrect alignment tool (or none)was used and the gearbox input shaft has been forced into an unaligned plate. The plate gets damaged and out of true and thus vibrates against the flywheel and/or cover. A test for this is that the vibration lessens or goes away when the clutch pedal is depressed and the damaged plate is flattened out. As new clutch parts are built so accurately compared to 30 years ago, balance is rarely a problem but damage is because the materials are less robust.
Nick Nakorn

W
Fair enough - unbelievable but believable
Nick
That wouldn't apply in this case as the driven plate was not involved in the balancing process which in itself exposed the problem
willy
William Revit

WC,

That is Bull sh#t !

They threatened you, THEY THREATENED YOU !!!

That so does not work in my book, thank you jesus, for making me born in a nation with 350 million guns, a Trillion rounds of ammo, and a set of fully protected constitutional 2 amendment remedies

Where the F#ck do they get off threatening you.

How is there incompetant retarded CEO with his looser lazy company that cant whittle a tooth pick become your responsiablity to stay hush because they lack the mechanical ability to properly make a simple clutch cover

If they want your silance to continue to manufacture a defective deadly product, then they sould but up the silver... like $250,000 before monday 8am or else your dropping a dime and a photo of there clutch cover and how it had to be corrected to become useable the to your nations version of our Federal Trade Commision (FTC)... and id remind these idiots that failing to deliver the funds will most definatly result in gov jack boot thugs busting thur your office door in full urban military attire with a server hunger to shoot any black employees that dont have there hands in the air begging dont shoot.

Threats are something that should NEVER be allowed to go unchallanged, seriously what guarantees did they give you there not already comming after you as a pre emptive strike just to make an example outof you

Buddy... time to take some Polaroids of there children playing at school and a nice close up of a brand new 12 gauge pump shot gun and with accomping box of shells and a note that says "You treatened me,
pay up, I want my dam money, NOW !"

Prop
Prop and the Blackhole Midget

This thread was discussed between 13/03/2014 and 04/02/2015

MG Midget and Sprite Technical index

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