Welcome to our resource for MG Car Information.



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 - 1st Day Engine Overheating & Knocking

Just bought a 1978 midget 1500, lovely wee car only done 68k & tons of paperwork with it so very pleased. Anyway drove around 3 miles & stopped for fuel & noticed a puddle of water from the expansion tank upper pipe connection to the radiator (Tank connection not pipe leaking). Took it back to guy I bought it from who assured me that this was not a problem as it was only an expansion tank so drove back the 28 miles home smiling in the sun with the roof down. 1 expansion tank on order,,, took car to shops & back temp gauge was around 3/4 but the engine around the rocker cover was smoking & the car was making a horrendous (knocking/rasping) noise on acceleration, revving it out of gear sounds okay though. As the car was cooling down I could hear it boiling & the expansion tank is cold & the engine very hot. Sounds ominous looks like I have been sold a dud,,,,is the expansion tank so critically important to the engines cooling system??? (Gutted)
j weir

LOL - don't be gutted for first things!

Nothing is unsolvable....

First things first - buy yourself a haynes manual - if that wasn't included in the paperwork (and, if not - it should have been - it's more important than anything else!)

Secondly, don't buy anything new to change the engine, until you've got used to the car.

If it's just the connection, then, reconnect it, and it should be ok.

WHERE exactly was it smoking from?

Rasping can be sorted out with some history - mine does it if it's not been serviced/tuned up/had some bad petrol in/had a stranger tune her/whatever other mood she's throwing at the time!

WHEN was the last time it was serviced, had it's carbs set, filled up with DECENT petrol????

Assume nothing - start at the begining - and I'm sure you'll get that smile back again - and don't be selfish with the sun!

These are tough little cars, I once drove back from France with a blown head gasket which gave similar symptoms to yours. Eventually the temperature gauge dropped down showing that there was little or no water in the system. After refilling the car still managed to get me home!
Firstly allow the car to cool down properly then refill with water using the hole in the top of the thermostat housing, squeeze the top hose and try and make sure that it is completely full,with no air locks. Then bring the car up to temperature,you may get away with this, hopefully your problem was the faulty expansion tank followed by overheating caused by the lack of water. You have deffinatly done the best thing by finding this forum, any problems you have will have been seen before by someone here and should be relatively easy to fix.

Good luck Carl
C Bintcliffe

sorry but if you've just bought it should you not return to the seller and let him fix it?

i just assume you agreed to buy a functioning car and he has not mentioned anny know problems.

The problems might not be big but should not be your problem imho
Onno Könemann

It sounds like you may just have a faulty thermostat...remove it & see what happens.
Dave Rhine ('78 1500)

Thanks for the feedback people very helpful indeed especially Carl, sounds exactly the same kind of problemo. I let it cool down then took it round the block all back to normal & no tapping etc although temperature creeping up fast. Will wait for new tank to install before refilling it & taking her out again. I realise after some further reading that the system is under pressure & with the expansion tank leaking has probably both scavenged the system pressure & starved the engine of cooling water.
j weir

I have to agree with Onno... (sorry about your rep Onno, its trashed now...LOL)

if you a purchased a running trouble free car, then he is screwing you over, Certianly have a good "CLASSIC" british mech look it over, if it is just a bad stat, thats one thing but if its a cracked head or blown HG that a completely differant religion

why should you volenteer to be the stoggie becuse he lied. major mechanicals are not the same as small normal wear items youd expect...a belt, head light bulb, a stat... sure thats life, a hole in the top of the piston is a differant church altogather.

Pro P

id go for thermostat removal 1st, it will only take 5 mins and an 1/2" af spanner, if it is that failing to open it will give you the symptoms you have reported, the coolant will all boil up and blow out of any weak spot or connection. you check the stats operation by dropping it in a pan of boiling water to see if it opens up. it would be safe enough to go down the shops again or a few runs around the block without it to see if you still get a temp rise or pressurisation of the hoses, if you get either then suspect the head gasket. a good sign that it is the head gasket is an oily film on the surface of the water in the header tank (only look after the temp has gone back down) and by looking at the dipstick to see if if the oil is a milky grey colour. if this is hard to determine then take the rocker box cover off and look to see if the oil there looks frothy and milky, if it is then get it back to the seller because he would have been aware of this before he sold it. if it was just the stat then you will get a new 1 for about a fiver and its happy days.

da cook

I'd go with getting a knowledgeable classic car mechanic to look at it

Also for all owners I strongly recommend buying an owners Handbook as it will tell you so much about running and fully servicing the car -

Read other threads on here to pick up tips and info

For low mileage and little used cars the best thing is to use them as often and regularly as possible to iron out all the things that have built up because of lack of use plus you'll get to learn about your car and its quirks

There's no reason to put up with faults (unless they are very minor) as a classic car can be made very reliable with use and servicing

Good luck with your car Spridget are great classics and fun
Nigel Atkins

This thread was discussed between 19/06/2010 and 20/06/2010

MG Midget and Sprite Technical index

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