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MG Midget and Sprite Technical - Now what do I do ?

Hi all. Well, today i finally plucked up the courage to start stripping Mertyl, YET AGAIN, but all the smiles and the laughter soon died when I found half of a valve guide laying in one of the pushrod cups !!!. The expletives flowed for the next hour or so. Question, can i simply put one new guide in or, as I fear, has the whole head got to be done. Pop, if your reading this, come on over, i'm sure between the two of us, we could get at least one car going, lol.
D J P Hewett

DJP,

Id think your okay. cant say for certian, you will have to pull the head and a new guild installed, the push rod hole goes into the block but hits a flat horizontial floor that the rod goes thur into the lifter tappet that rides agianst the cam

id fish out all the pieces with a magnet on a stick before pulling the pushrod, infact you may be able to put a strong magnet on the push rod and attract any little slivers as you pull the puch rod out

prop
Prop

what do you mean by 'pushrod cup'? Are you saying the broken-off piece of guide was still on the top of the head, or had it found its way down one of the pushrod holes as far as the tappet / cam follower?
David Smith

Hi Prop, sorry for calling you pop earlier. Have given up worrying about tapping in one guide only and iv'e put a whole new (to Mertyl) head on. Unfortunatelly this hasn't helped. New gaskets fitted, all ancilleries cleaned and checked, everything fitted and guess what, IT WONT F_ _ _ING start. I swear, i'm so close to giving up with this car. I really don't know what to do now.
Dave, yes the broken off piece of the valve guide was in one of the pushrod cups. fortunatelly it was resting just in the top of the cup, resting against the pushrod itself. One interesting thing i have discovered is that the head that was on the car only had single springs, the new one has double springs, mmmm.
D J P Hewett

D J P

Oh good lord, single springs ah... a whole new head, thats a great start and an even better idea.

so she wont start...temper mental arnt they 8 * )

do you have spark at any of the plugs...pull the plugs leave the wires on and ground the plug against bare metal on the thread part of the plugs...look for the blue spark when turning the engine over

next look in the carbs while turning the engine over and look for fuel mist

next do a compression check on all 4 cly

did you use (rule of nine) to gap all the valves they should be around .012 to .015

do you have points or electronic igntion

keep us posted

Prop
Prop

You should take heed of Prop's advice - after all, he has a huge amount of ongoing experience in starting engines that are "temper mental" - I rather like that Malapropism! very apt!

Guy
Guy Weller

Hi Prop, all the things you suggest, with the exception of the comp test, have been done, all to no avail. But, now the good news, having got so peed of with her myself, i gave up and called a mobil mechanic. He turned up at 08.45 this morning and after 35 mins under the bonnet (hood to you), Mertyl was up and running. I'm convinced she was just throwing a tantrum because i brought an mgb roadster as well (which sailed through the mot yesterday), so i now have two mg's up and running, yippee.
D J P Hewett

B-----ks, I knew it was too good to be true. Not quite 5 hours the damned thing lasted before she coughed and spluttered to a halt as I was heading out to the MGCC natter. I know the problem is fuel related but I really can't fathom out where or why. In all seriousness folks, If there is a midget magician living near the colchester area who can spare an hour or two, please, get in touch before I totally loose the plot. I love Mertyl dearly but i,m rapidly running out of money and patience.
D J P Hewett

WILL YOU STOP DRIVING THAT RUDDY CAR AND SELL IT TO THE PERSON WHO OFFERED YOU MONEY .........
rachmacb

Hi Rachel. I'd love to, but i think he's had a change of mind. Now theres a suprise. photo is of the roadster, it's bright so put your sunglasses on.


D J P Hewett

If you really belive its fuel related... and the carbs are okay,, and it just died all of a sudden...

look at the fuel filter that it hasnt picked up some big chunk of trash.

then make sure the fuel pump ground wire isnt rusted or dirty and has good wire connections at all the bullet connectors back to the power source, might even run a tempory wire in place of the orginal for a few days...but focas on the ground wire at the pump

might even ask around to see how to test the fuel pump to make sure that its working okay. could be the points in the fuel pump needs cleaning and re-adjusting, sometimes it can devolop a film on the contacts if it hasnt been run in a long while
Prop

Love it - now - haul out the engine and put something big and brutish in - and come up to the Anglia Autotests!!!

Have you asked him? Could be he'll make an adjusted offer.

Alternatively - enjoy this B - and park her up to work on over winter - mind you, this ruddy weather, it might as well be winter .....
rachmacb

When I had my TR4...

Build up of crud above the needle valves in the carb float chambers?
Need to take needle valve out to really check. As the fuel float level will look fine by the time one takes the top of the float chamber off, because the fuel can slowly seep by.

I got this from time to time, despite installing filter and replacing hoses. I was coming to the conclusion that the replacement hoses don't like unleaded petrol and disolve and break off little bits internally.

Naturally it usually occurs just as one starts a ten mile section of motorway before the next turn off.....

Roly
Roly Alcock

good call on possible bad connection to pump or possible fuel blockage

if it's the fuel pump itself replace it with a more reliable electronic type they're not expensive especially for the reliability they give

Nigel Atkins

Morning all, please tell me what sleep is like as i am not getting much at the mo. Right, fuel is delivered via a manual pump on Mertyl and this has been thoroughly checked, all fuel lines checked, cleaned and replaced where necersarry, fuel filter is brand new and showing no signs of contamination. The carbs themselves seem to be the problem and Roly's thoughts could be on the right track and thats where my problem is. I am competent enough to do basic service stuff on most cars but a mechanic i aint and the thought of stripping down complex bits like carbs terrifies me (wimp, i know). This morning,05.35, i decided to try her again and she fired up almost straight away but after a few seconds she was doing a very good impression of an overloaded washing machine on 3 cylinders.
D J P Hewett

DJP
I there any circumstances that seem to lead to your problems? You really could try taking the tops off the float bowls to check for muck in there. Maybe a couple of under bonnet photos would show something up.

Cheers Carl
C Bintcliffe

on another thread here there's talk of some mechanical pumps having a plate before the pump and if it needs it and you haven't got it then pump wont be happy, sorry can't remember which thread but it's recent

but cleaning the carbs could well be all that's required

push comes to shove run some Redex thro' (like we used to to keep things clean) and and to tank to use it up - follow instruction on label of bottle tho'
Nigel Atkins

DJp,

If its jumping around like a rodeo bull on 3 cly, Id say its time for a good cleaning and RE-adjustment
, when it does it agian use a plastic screw driver handle and rap it fairly harsh on the float bowls several times. sometimes that will dislodge any junk thats caught up in the carbs and make it run better. but thats just a fast fix to get to point A to B

Considering the P.O. did a bang up job on the head and jimmy rigged it to no end, maybe a specialist wouldnt be a bad idea to have a look at the carbs, no telling what jimmy rigged went on with the carbs.

Im confused by the fuel pump...you said its machinical?

what engine do you have agian? I thought it was a 1275

on the 1500s and the (1098?) that have mechanicals ive seen in the postings that the camshaft lobe wears down and the pump dosnt flow as well as the lever cant reach as far...and some I think the diaprame can go bad, sorry beyound that I dont know hardly anything about mechanical fuel pumps

you might try removing the pump and making a blanking plate for the hole then get an electric pump that is no more then 1.5 psi
Prop

I'd forgotten which car you had

might be a good idea, if you want to, to display your vehicle profile and have a photo if possible to give an idea of the model you have
Nigel Atkins

DJP - Sorry, what is your name? -It seems sort of unfriendly to address you without knowing your name.

It is difficult to diagnose a problem without clear symptoms. Saying it won't start, or it is running like an overloaded washing machine doesn't really give enough information!! ;-)

But there is a sort of consensus that the problem is fuel related. One possibility is that there is a bit of dirt caught within the fuel jet tube of one or both carbs. This can give intermittent running problems. The jet needle, when it drops into the jet can push the dirt back, clearing it for a while. It then appears to run perfectly for a bit, but eventually the piece of dirt works its way back into the jet again and starts to cause all sorts of erratic running problems. Then it may seem to correct itself again, and so on.

This is only speculation, but I have had this happen and it is a very frustrating fault, and not at all obvious. The solution is to remove the jet tube and disconnect the feed pipe from bottom of the float chamber. Flush it through thoroughly and reassemble. It may, or may not, cure youtr mystery problem! But worth a try I would think.

Guy
Guy Weller

Evening all, Dave here. I have just read through all of the above comments and theres some really helpful stuff, thankyou.
For the benifit of all, Mertyl is a very late '79' 1500, but she wasn't registered until sept '80'. An interesting point brought up by Nigel is the mechanical fuel pump. Every old car iv'e owned has nearly always had the afformentioned block type gasket beetween the engine and the fuel pump, no suprise, Mertyl hasn't so thats one train of thought for the morning, (I have got one in my spares box).Nigel also mentions ading a vehicle profile, and i would love to but i haven't a clue how to do it, so instead i'll try to upload a few pics on this thread.
Ok, thats not happening either, sod it, i'm off to bed. Night all.
D J P Hewett

Hi Dave,
Wow two reasonable ideas, that’s well beyond my normal limit

Found this – (item 75) - Spacer- Fuel pump UKC8523, on this page http://www.mgocspares.co.uk/acatalog/MGOC_Spares_LINES___HOSES__MIDGET__184.html#l70

- note - ‘Due to engine variations please contact before ordering’ (petrol pump)

And you may need two (different?) gaskets if using spacer block

Now getting your vehicle profile up is dead easy or I wouldn’t have been able to do it

You could copy and paste the next bit to print out and follow:

On your log in page for this site look for the top of the three boxes on the l/h/s of page

click on - My Cars

click on – Add a new entry

fill the details in the box (only those underlined are shown)

click on – Upload – (and a box will appear to download your photo from your computer files)

click on Browse (and find your photo, once you’ve found it double-click on the photo file)

then click on Upload (in the first box)

once upload has completed (you’ll get a message) click on Close>>

finally – click on Submit details – ya done!
Nigel Atkins

Nigel,

Your the Man!!

Im passing on my newly acquired throne name for your personal use and enjoyment, The crown clearly was made for you.

Nigel ... "The All Knowing Midget Oracle"

Good call, I hope your suggestion works out well for Dave

Prop...once agian is happy to simply own a Black Hole.
Prop

Dave,

Do not be overly concerned about the lack of the spacer block on the fuel pump of the 1500. Two different pumps are available for that engine. They differ in the length of the pump arm that contacts the camshaft. The longer arms gets the spacer block. The shorter ones doesn't.

Can't add much on the no start that hasn't already been said. Checking and cleaning the carbs isn't hard.

Lee
Lee Fox

oooos 'e calling a orifice !? :)

yeap I agree more likely carbs than pump butat least that's another avenue if cleaning carbs doesn't turn up the root of the problem
Nigel Atkins

Hi all, Yippee, i,ve slept 9hrs......with the help of a drop of bailys. Now it's time to crack on and get this tempremental old girl up and running......again.
D J P Hewett

WHOOPEE, HORAY, THE LORD BE PRAISED. Yes folks, MERTYL is up and running, sweeter than she has ever done in my ownership. The problem........ the tappets where a fraction too tight therefore the valves weren't quite closeing fully, tappets adjusted, carbs balanced, everything double checked, turn the key and.... pure joy. She started first turn and ran as smooth as you like. Out for a test around the block and it was fab, smooth, quiet and much more response to the throttle, it even felt like she had more power and i'm assuming thats down to the twin springs on the new head. Thanks to all for the advice and sorry I was such a pain and pessamist.
D J P Hewett

I don't believe the double springs, in and of themselves, give you more power. Stronger springs just let you turn more RPM without valve float. So, unless you are talking about power at very high RPM, I'd say the power diff is the tuning and perhaps different head specs from the old to the new.

Anyway, glad it all works now.

Charley
C R Huff

Thanks to all for the advice and sorry I was such a pain and pessamist.


Dont worry, thats my full time job here on the BBS, No one does it better then me. LOL HAHahaha

Im glad it worked for you.

Prop
Prop

SELL IT - NOW - and don't touch it 'til you've the money in your hand ......
rachmacb

Hi all, guess who's a happy bunny. Prop, your not allowed to be the only pessamist on here, i take it they have job share in the us of a ?. Rachel, i know your right... BUT, driving her down the road tonight, with the engine singing so sweetly, i fell in love with her all over again. I need to have a serious think about which one to sell, the roadster is insured and taxed as of tuesday so once iv'e had a good blast in her (Rita, after my mother, bold, brash and loud, lol) i will decide which one to sell.
D J P Hewett

Rach,

Am I missing something, why do you want Dave to sell so bad, granted its got some issues here and there but dave seems to be knocking them down one by one, personally I think he sould keep the midget and sell the B...but then Id keep both.
Prop

Yup - I know what he was offered ... and what he bought the B for - and how much he could sell that for - and then he could go and buy a very very very nice Midget - and come and play with the rest of us at the next Autotest - and know he'd get there and not be sat on the side of the road while I drive past ;)

Some folk just like to drive though - not spend ALL their time playing with an engine that's never gonna run .......
rachmacb

This thread was discussed between 11/08/2010 and 16/08/2010

MG Midget and Sprite Technical index

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