MA10 not running right - Please Help!

Hi,
My K10 has recently developed some serious issues. It idles just about ok, doesn't seem to be misfiring or anything but could be more stable and will occasionally stall.

More seriously, when given partial throttle it hesitates and then stalls. Sometimes if its given full throttle it will rev up ok but with a little hesitation.

I changed the fuel pump & filter, checked the ht leads, plugs, cleaned the dizzy, checked the vacum hoses but can't seem to cure it.

Today I had a look at the carb and there was a something that concerned me (not that I know anything about carbs). There didn't appear to be any fuel coming out of the secondary main jet (the one without the choke butterfly above). When I gave it some revs the primary main jet really seemed to be gunning it but the secondary main jet remained dry. Is this normal?

Thanks!
 
Possibly a carb problem, its cheap enough now days if you can do it yourself to change the carb over for one out the scrappies etc...

Check your HT leads, maybe change them, also check plugs for condition and the inside of the dizzy cap, spray some wd40 into the cap and give the contacts a clean
 
That's normal operation for the second barrel, it opens under mid to high engine load.

Could be blocked jets, a weak spark or both. If you can get hold of them I would try replacing the carb, HT leads and possibly the coil.
 
Ok well I got the carb off and in the kitchen last night (the girlfriend ain't happy).
I'll get some carb cleaner and instant gasket on the way home from work and then spend the evening taking it apart, cleaning the bits and bobs and putting it all back together again.

If that doesn't fix it I've got HT leads, spark plugs, ignition coil, dizzy cap & rotor arm waiting for me at central autos should I need them. All that for £55 ain't bad but still more than the cars worth.

Should I just scrap it?
 
Dont give up on ur car m8 I had a problem wit my micra something very similar to this after alot of trying to find a solution I got another distributor and its been perfect since no repairing just replacing
 
To be honest I wouldn't try and split the carb. I would try and get a second hand one.

The carb is quite intricate and its a bit of a specialist job to clean and reassemble them successfully.
If your going to have a go you will need a proper gasket for the top cover at least.
 
To be honest the idea of taking it all apart and just making it worse given my lack of experience was worrying me. I think I'll just get a can of carb cleaner and give it a good blast inside and out and try it out.

It's just so frustrating not to know if the problem is electrical or carb related.
 
try putting it onto winter mode from the airpan, mine did the exact same last week because of the cold weather and would stop once the temperature was right, the winter mode fixed it, but i lost acceleration, so i swapped it back :p
 
Keep at it and I'm sure you will get it sorted. I know these sort of problems can be very frustrating.

Is the hesitation and stalling when you open the throttle intermittent or does it happen all the time?

If the engine starts easily and idles ok, but stutters and dies when you open the throttle then its most likely to be cr*p in the carb blocking the main jet.
 
Ok well I had the carb in the kitchen sink and gave it a good jetting all over with carb cleaner. Re-fitted it and it hasn’t made a spot of difference. In fact it seems to be getting slightly worse as time goes on as it’ll only idle for a 10 seconds now and then just gives up.
I’m beginning to think the problem is electrical. Possibly distributer or ignition coil. It’ll get the leads, plugs, dizzy cap, rotor arm and coil from central autos. If that doesn’t fix it then I know somewhere not too far away breaking a K10 so will go get the dizzy and carb. If it still doesn’t work after all that then I’ll set fire to it and see if that helps.
 
Still sounds like the carb to me, especially if it is starting ok and idling without misfire until it dies.

A couple more things you can check...

Have you got contaminated fuel? - did the old fuel filter look brown or black, and what does the new one look like now its had a bit of fuel pumped through it. My mate has just reminded me of one he worked on a few years ago with similar symptoms that had rust holes in the petrol filler neck that let water into the tank when it rained.

You've fitted a new fuel pump but its worth checking that you are getting fuel through to the carb. Have a look at the sight glass on the front of the carb and see if the float chamber is full to the mark in the middle of the glass (you will need an inspection mirror or something similar to be able to see it). However as the pump is mechanical it can take quite a bit of cranking or idling to pump enough fuel to fill the chamber.
 
I think you might be right... I just fitted the plugs, leads, dizzy cap/arm and coil and its exactly the same as it was.
I won't be able to get the used dizzy and carb till after xmas now. I genuinely hate this car right now grr
 
Oh yeh and I had a look at the float chamber level and it appears to be full to the middle so i think thats ok.

Good point about the contaminated fuel though. Maybe water has got in somehow... I think theres about £20 in the tank. What would you suggest? Draining it from the tank and then sticking some fresh fuel in from a jerry can?
 
Oh yeh and I had a look at the float chamber level and it appears to be full to the middle so i think thats ok.

Good point about the contaminated fuel though. Maybe water has got in somehow... I think theres about £20 in the tank. What would you suggest? Draining it from the tank and then sticking some fresh fuel in from a jerry can?

If water is getting into the tank through a rusted filler neck or similar it will usually happen slowly over a period of time without any symptoms and the tank will start to rust. You'll usually then see orange petrol in the fuel filter.

There's a drain plug on the bottom of the tank, but unless your seeing any evidence I would try the new carb first.
 
Ok well there doesn't appear to be any crud/discolouration in the fuel filter and this problem came on quite suddenly so I guess it isn't fuel contam.

I had a play with it this afternoon and noticed the following things:
It ticks over much better when the auto choke butterfly is closed. Once it warms up a bit and the butterfly pops fully open it seems like the mixture is too lean and the engine shudders to a halt. If I hold the auto choke butterfly 85% closed and rev it the engine seems to run ok.

So is it under fuelling?
 
Went down the scappy on new years eve morning and butchered a carb and dizzy from an old k10.
Decided to swap the dizzy over first as I was sick of looking at carbs.
Fired it up afterwards and it appears to be fine now.
So I've now got a spare carb in the garage if anyone needs one?
 
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