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MG Midget and Sprite Technical - Midget trouble starting

Hey all

After any help if possible

I have a fully restored 73 black tulip midget
Full nut and bolt resto - everything new or rebuilt

I seem to have trouble starting her
Compared to my tired Sprite which starts first time it's terrible
Unless warm never first first or even 3rd time

Yesterday wouldn't start at all and when turning over it was showing no oil pressure
I tried for a while until the battery ran flat

Then I jump started it of the tired Sprite and she started first time with perfect pressure

Now the engine is fully rebuilt by a good engine builder and all else is new

My thoughts are a bad earth or duff battery -

Anyone got any suggestions ?

Cheers
richard weaver

what voltage are you seeing at the coil when cranking?
David Smith

Swap the batteries over, and go on from there?
Guy W

^ WHS.
Check battery voltage at rest too and when running check the alternator output. Is there something draining the battery e.g. bootlight?
Jeremy Tickle

Thanks so far I'm away till Sunday eve so I'll have a look when I get back

There's nothing draining the battery as nothing hooked up - it spins the starter motor well but normally just takes several attempts to get it going - which is annoying as as I said literally everything is new or rebuilt - I should say however it's got accuspark ignition but bought a second unit from stealth and no difference
richard weaver

Is it a mechanical or an electrical fuel pump? If the former if the fuel level drops in the cstbs between uses, then the engine has to spin a bit before the carbs fill. If electrical, then l presume that you know to turn the ignition but wait for the pump to stop clicking before firing the starter.

Apologies for stating the obvious!
Guy W

Guy
It's a 1275 with electrical pump

There's an inline fuel filter so Defo fuel
Ignition on - pump clicks then stops after a while - filter full attempt to start and jut turns over after 5 or 6 tries she fires

Compared to the Sprite which starts almost immediate with 103k miles on - midget has 204
richard weaver

OK, so sorry, starting sequence is right.

It still has the symptoms of a delay in getting the fuel charge into the engine. Did you set / adjust the carb float levels when rebuilding them?
Guy W

Next time ... pull the float chamber lid and see if there is fuel in the float chamber if no fuel, its a sticking needle valve (most likely)

Next test the spark plugs for foul...new engine means the rings havent seated yet and the plugs get a little oily, then no workie... btw, if you ground the wrench part of the plug and get a spark... thats NOT good, but if you ground the thread part of the plug and get a spark... thats good

Grounding Hex nut on plug gets a spark ... BAD

Grounding plug at threads and gets a spark = GOOD

ALSO... look to make sure the carbas are not overly lean

You may want to temporarly go back to points and condensor, there are numerous examples of the accu spark system not funtioning well

And last... did you set the timming to 10 degrees at 1000 rpm ((( WITH A TIMING GUN ))) haha, sorry im sure you did

And last... when it is running for say 1/2 hour, feel up the choke cable to see if it hot, that would be a bad grounding issue, also (engine off) feel up the coil and the various coil wires for high heat

Okay one last thought... check the wire connections at the coil, if loose (common) those could be an issue

And make sure there is a.good healthy flow of fuel (remove fuel hose at carb and turn over key )

Prop


Prop and the Blackhole Midget

X2 guy while I was posting

Im assuming orginal fuel pump and not a replacement higher pressure pump ... beyound 3 psi
Prop and the Blackhole Midget

This may be stating the obvious but do you have the right amp battery? May have enough oomph to turn it over but not enough to spark it. (Just going on the fact it starts when jumped).
Jeremy Tickle

Jeremy

I was wondering that also... but I went the direction of a bad ground because it starts right away when jumped, but not so much on its own battery, so im guessing the jumper battry is grounding both cars
Prop and the Blackhole Midget

Great minds Prop :) LOL!
Jeremy Tickle

Thanks for your help this far

The car does run well when going -

And when warm it seems to start easier

I've had it on a rolling road for basic set up after it was all built and all timings set - it has also got a metro turbo / Kent 266 cam and turbo rockers so it's slightly different timing to standard

The file pump is the aftermarket type without need for vent tubes

There is Defo fuel going to each float chamber as played around with them a while back before I worked out the fuel pump was fubar


I think when I get home I'll swap the batts over and check all the earth points to make sure

I'll also check the VoLts at the coil
richard weaver

I wasn't suggesting no fuel in the float chambers, but possibly the float levels are just slightly low. The effect would be that initially, less fuel is drawn out of the jet to atomise. It then takes more spins of the engine to draw the initial fuel charge into the engine. Once drawn through and with the engine then running there is sufficient induction vacuum to keep drawing the fuel through so it then runs properly.

Just speculating.
Guy W

I had a similar problem and suspected electrical issues associated with ignition switch. It turned out that one of the two carbs had lost it's setting for the butterfly so that only one carb was doing anything- the other was still shut. Same symptoms as you were seeing and oddly if I powered directly to the coil it started ok - hence the false lead pointing to electrical issues.
Graeme W

It could well be it just needs some miles on the rebuild

How many miles are on the new clock?

Prop
Prop and the Blackhole Midget

204 prop
richard weaver

How about it's just so new and the cilinders cause a lot of drag for the piston rings? Mine also had difficulties spinning when just rebuild. And the rings don't seal very well yet, so some oil above the pistons might make the fuel mixture harder to ignite maybe.
Just take it for a 200 Mls trip and then see what happens.
Alex G Matla

204 !

Yeah im with alex, it may take at least another 120 meters before you get all the grimlins out....haha

But seriously yeah with fall leaves in the air, id say pack a basket and take your favorite girl for a 2-300 mile day trip to see the folage, and I think you will have a much noticeable better performing car

I dont know of to many 3 year old children that can run a 4 minute mile

Btw... 204, the (4) was a nice touch, I liked that and made me smirk, simple and elegant

Prop
Prop and the Blackhole Midget

Something you might try for the next several hundred miles is to widen the spark plug gap out to around 30 to 35 thousands with fuel being as bad as it is, and no doulbt some blow by oil sitting on top of the pistons its not doing the plug gap any favors if there set to normal spec

Once the engine has matured a bit, then go back to a more basic spark plug gap setting.

Prop
Prop and the Blackhole Midget

Just tried to start the car again and again not starting - hooked up the other battery off the Sprite and it started first time

The non starter is a 73 1275 and I had in it an 038 battery - am I right in thinking this is the wrong type and better suited to the 1500 model ?
richard weaver

I think the 038 is correct

1.How old is the battrey in the new rebuilt car (midget)?

2. Has the battrey sat for very long with no use (older bat) .

Im thinking your battrey is gone duff, this can happen because of

1. age, 5 years for a battreys are like 70 year old people

Or has gone duff because of non use... what happens with out any use for 12 to 18 months the cells inside get caked up with what is called... solidfides ? And the make a bat dead before its time, some of thr new battery chargers have a feature that works 1/2 the time for resurrecting solidifed battreys (for me 2 rose from the dead, and 2 were just dead period)

The other thing if the battry checks out is im wondering if you have some kind of grounding issue

If possible id install the batt your jumping from and drive with it for a few days if the same problem is still there then you know its the car (wiring) but if the car starts and runs good and as expected, then you know the (previous) battrey is the problem

Prop
Prop and the Blackhole Midget

.nnn
Prop and the Blackhole Midget

The battery was 13 months old - the car has been used but not a daily driver

I took it back to the place I bought it from and it has a 2 year warranty / they checked it and said although showing 12 v the battery tester said replace so I think it's just a duff battery - I'll put it on tomoz and see if that works
richard weaver

Did you get the new battrey?
Prop and the Blackhole Midget

Yea brand new battery so I'll try that and see how that is
richard weaver

Good luck... id say theres a good chance thats the issue

Just another thought... make sure the battry post arent making contact with the bulk/fire wall...some of those batt get pretty close

Prop
Prop and the Blackhole Midget

This thread was discussed between 16/10/2015 and 23/10/2015

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