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MG Midget and Sprite Technical - HGF?

Does this look like a blown head gasket? I'm rather hoping that it may just be condensation build up as the car has not been driven for the last year and I only start it once a week for 15 minutes or so, just to recharge the battery etc.
There is no sign of blue smoke but I do have to enrich the mixture at the carbs every time I start it.
Thanks


BH Harvey

No idea wheter you gasket has actually blown or not, but why has your car not been driven?! come on man!

ha ha, sorry, joking aside... I think everyone has to pull the choke and enrich the mixture when they start, thats what they choke is for!

As for HGF I think you can get such deposits if you just don't use your car enough and you get the dreaded 'mayo'! I have a k-series rover 25, so I know (a bit) about the dreaded HGF! ARGH! ha ha.

Anyway, I don't want to get your hopes up but it might just be a bit sludgey from little use....

Someone will be along to correct me soon (it's what usualy happens! :-))

cheers
Malcolm
M Le Chevalier

Probably just condensation, but a compression test will probably confirm.

If you want to charge the battery, use a battery charger/conditioner.
Dave O'Neill 2

It will start with the choke, but as soon as the choke is released it dies again. This means that I have to start it with choke then rush round to the carbs to turn the jets down (having no doors, bonnet, wings etc helps).
I don't see how it can slip out of adjustment every time so assume that I am compensating for burning coolant.
It runs well when it is running though.

Really hoping it isn't a head gasket as I plan to MOT it in a few months. You know, the grand midget plan with a sensible budget and clear cut timescale?
BH Harvey

Head gasket is a more pleasant cause than a cracked head, which is also a possibility.

It could be inactivity. If you get the car running and in use properly the mayo will disappear if that's the case. If it persists you'll need to remove the head. If there is nothing obviously wrong with the gasket, get the head crack tested rather than just replacing the gasket and hoping for the best.
Paul Walbran

Running the thing 15 minutes is the best way to create this situation. It produces water vapour, and it takes 15 or 20 minutes <under load> to get it hot enough to start to evaporate the water. Very common on cars driven short trips at low speed; it is the worst possible operating condition.

Your choke should have a cable that will lock on at any position. There should be "fast idle" before "enrichment"; you pull the choke out all the way, start the car, push the knob in a bit until the car warms a bit, then push it in some more until it is warm when you push it in all the way. No need to screw up the carbs. If it does not work that way, then the carbs need to be set up correctly.

Both the condensation and the carb misadjustment are contaminating the oil badly; get it hot, change the oil and filter. Do NOT start the car and run it less than full hot for a half hour minimum - you are only making things worse.

FRM
FR Millmore

I'm with Dave get a battery conditioner rather than running an engine for 15 minutes

I'm sure you've seen my posts about using the car and owners Handbook and 36,000 mile service so I wont go on

If you want I can post here too

As FRM says the mayo could be this only running for 15 mins and choke business

The choke business could also be lots of things but could be sorted out or found by doing a full and proper 12 month service on the whole car (or what bits are on it now)

Just for info now
- I put this post in another thread about HGF, compression tests were favoured

>>As far as head gasket going some signs that you sometimes get are

missing whilst running
loss of power
coolant in the oil (white mayonnaise but this can also be from short journeys only)
gases in the coolant
runs hot
lost of coolant

these things are not always all present or noticeable at the beginning at least

You can buy a Frost block test kit if you think it really might be HGF - http://www.frost.co.uk/automotive-engine-and-mechanical-tools/block-tester.html
also see, this page, ignore title and very top of this web page - http://www.frost.co.uk/how-do-i-flush-and-refill-my-cooling-system <<
Nigel Atkins

Put the battery on a trickle charger now. Hopefully next I start the engine it will be ready to drive.
Just a few questions. Can you use diesel oil as a flushing oil? and does coolant water have to be distilled to prevent a build up of mineral deposits?
BH Harvey

I'd buy some proper flushing oil. It's not dear. Forget the diesel. Your coolant should be at least 30% antifreeze to 70% plain water all year round to prevent corrosion.

Bernie.
b higginson

I'm with Bernie get the proper flushing oil

it depends on your tap water if you can get distilled that would be better and about a third anti-freeze, I like to premix the coolant before putting it in other don't

from my usual advice post (I can post the full version if you've not seen it and want me to)

- For a coolant change drain the whole system - engine block, rad and heater matrix if you can get any of these out to give them a good shake at the same time as flushing and back flushing then all the better - the sequence is flush, back flush, flush, clean, flush, back flush and flush again until the water runs clear, refill with the correct coolant mixture but bear in mind in tap water isn’t always the best water to use

also a good oppitunity to clean out the heater and fan box and rewrap the heater matrix with foam to make it more efficient and renew the box bottom seal

lastly just noticed two glaring ommisions from the possible signs HGF list

>Sign of oil in coolant
>White ‘smoke’ from the exhaust (you’ll notice a coolant loss now)
Nigel Atkins

I think from the information its too difficult to tell what it is. There are quite a few signs as mentioned of a head gasket failure however the signs are not always that obvious. This could be due to the lack of running the car or it could be more serious. A compression test would certainly help.
C Carter

This thread was discussed between 06/05/2011 and 19/05/2011

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