Little piece of S**T....

[kevo]

We have had a mini mayfair for around 11 years now....And,Its been Ok...All the normal things that usually go wrong..(How long have you...)..
Just lately its been a bloody pain in the arse....When its cold there is no responce from the go pedal at all...First gear even....The engine just stammers and would`nt pull me out of bed on a morning...I have changed/Checked the following :-

Carb twice,
distributor,
points,
condenser,
distributor cap,
2 x needle valves,
Set the points dwell,
Set the timing,
Checked the distributor advance weights + Vacume advance module,
Checked the spark on each plug with a tested...(Good and strong),
Changed coil,
Checked all valve clearances,
kept the dashpot full with oil,
new spark plugs,

The symptoms get better the warmer it gets...As stated 1st gear upover will not pull at all...Just balks out...I have noticed that the fist touch of the accelorator is the most responsive from that its numb and just makes the throttle open sound (Balks)...

Its a 1985 mayfair with 70,000 mls well looked after example.....

Any ideas guys....????Cheers Kev.

Edited by kevo on Friday 3rd August 17:37

Edited by kevo on Friday 3rd August 17:39

Edited by kevo on Friday 3rd August 17:40

[Hammer Zeit]

Oil? Have you over-filled it?

I had a similar problem on my XR2 race car when I changed to 4th there was no pick-up at all, too much back pressure our mechanic said. He drained about a pint off between practice and race.

The car was running well after that.

[kevo]

Hammer Zeit said:

Oil? Have you over-filled it?

I had a similar problem on my XR2 race car when I changed to 4th there was no pick-up at all, too much back pressure our mechanic said. He drained about a pint off between practice and race.

The car was running well after that.

Thanks Hammer....No oil checked and fine..Just under full mark....Dashpot oil to just over oilwell inside ...
Thank you....Kev.

[xxxy]

Possibly plug leads??
Dave

[Ferg]

Air leak on the inlet manifold?

[Christabel]

I'd def try plug leads. The little beggars are frequently the culprit..

Which reminds me... I need to try it on mine... there's a slight misfire which doesn't mean it doesn't pull (it was doing err more than the speed limit and upsetting BIG boy Beemers driving home up the M1 on Wednesday!!), but it's not quite at its most excellent.

Hope you sort the problem Kev.

[eccles]

timing chain really worn, putting the cam timing out.......?

[annodomini2]

Clutch not slipping? Leaking oil from spilt pin sticking through transfer case?

Fuel filter clogged?

[kevo]

Ferg said:

Air leak on the inlet manifold?

Just had the carb off and renewed all the gaskets....Took a look at the manifold gasket also...Which was fine.....Still to no avail.....

[Snake the Sniper]

When warm does the problem disappear, or just get less? Do you have access to a colourtune at all? It might be worth checking the mixture, as it sounds as if it may be going lean. Have you changed the air filter recently?

[kevo]

Snake the Sniper said:

When warm does the problem disappear, or just get less? Do you have access to a colourtune at all? It might be worth checking the mixture, as it sounds as if it may be going lean. Have you changed the air filter recently?

Hello SIR,...The problem does get better when warm...It dose`nt dissapear altogether but gets better..(At least i get a little more pull)...I have a co2 meter and have set the mixture to 2.0 - 2.5 and it seems to have made no diffrence.....I have checked the spark at the lead ends to sparkplug tops with my sparktested and this shows as being excellent...(I can open the tester to full gap on tickover...Approx 3/4 of an inch gap)...This makes me think the leads are fine....?????
Thank you....

Edited by kevo on Saturday 4th August 20:12

[Mr Edd]

I would check that you have a problem with the breather it could be either blocked or a cracked / badly fitting.

If you are setting the mixer by CO i would set at 4.5% as most engines i have dont like running to weak.

[Mr2Mike]

Blocked exhaust? If it's ont the original "pea shooter" type system then they can become very restrictive as they rust up internaly.

[kevo]

Thanks for all the help guys....I`ll try the breather + Exhaust next week...I`ll report back with the results...
Thanks....Kev.

[Snake the Sniper]

kevo said:

Snake the Sniper said:

When warm does the problem disappear, or just get less? Do you have access to a colourtune at all? It might be worth checking the mixture, as it sounds as if it may be going lean. Have you changed the air filter recently?

Hello SIR,...The problem does get better when warm...It dose`nt dissapear altogether but gets better..(At least i get a little more pull)...I have a co2 meter and have set the mixture to 2.0 - 2.5 and it seems to have made no diffrence.....I have checked the spark at the lead ends to sparkplug tops with my sparktested and this shows as being excellent...(I can open the tester to full gap on tickover...Approx 3/4 of an inch gap)...This makes me think the leads are fine....?????
Thank you....

Edited by kevo on Saturday 4th August 20:12

From that it sounds as if you're not quite sure what a colourtune is for. It's not for checking the sparks, as you'd already said you'd check them out. It's a replacement plug with a clear crystal instead of a ceramic part. It lets you see into the cylinder to check/corect the mixture at or near to tick over. As said, 4.5% is a much healthier number for CO2, as 2-2.5 is a bit weak, assuming you are giving a percentage.

[kevo]

Snake the Sniper said:

kevo said:

Snake the Sniper said:

When warm does the problem disappear, or just get less? Do you have access to a colourtune at all? It might be worth checking the mixture, as it sounds as if it may be going lean. Have you changed the air filter recently?

Hello SIR,...The problem does get better when warm...It dose`nt dissapear altogether but gets better..(At least i get a little more pull)...I have a co2 meter and have set the mixture to 2.0 - 2.5 and it seems to have made no diffrence.....I have checked the spark at the lead ends to sparkplug tops with my sparktested and this shows as being excellent...(I can open the tester to full gap on tickover...Approx 3/4 of an inch gap)...This makes me think the leads are fine....?????
Thank you....

Edited by kevo on Saturday 4th August 20:12

From that it sounds as if you're not quite sure what a colourtune is for. It's not for checking the sparks, as you'd already said you'd check them out. It's a replacement plug with a clear crystal instead of a ceramic part. It lets you see into the cylinder to check/corect the mixture at or near to tick over. As said, 4.5% is a much healthier number for CO2, as 2-2.5 is a bit weak, assuming you are giving a percentage.

I have only been using colour tune for around 20 or so years...And are quite aware what it does the yellow and blue tinge ect,Relating to the rich or weakness of the mixture....I find a more accurate figure from the CO2 thats all....I always found the colour tune fine for a base figure.....I did set the CO2 to 4.0% but the car did`nt like it (TOO RICH) And,Its due its test shortly which only allows the content to 3.5 CO2...
The manual figure given for my engine is-2.5 +/- 1.0.

Thank you....

[kevo]

Mr Edd said:

I would check that you have a problem with the breather it could be either blocked or a cracked / badly fitting.

If you are setting the mixer by CO i would set at 4.5% as most engines i have dont like running to weak.

Thank you MR EDD...
I think you have hit the nail on the head..Checked the breathing system and No Breathing at all through the pipe....I`m removing the chest cover tomorrow to try and clean out the gauze....But,It looks as if your on the ball sir....It would also go hand in hand with the symptoms i`m experiancing...IE:- More blow by when cold as the pistons ar`nt expanded and getting better as the engine warms up= less blow by as the pistons expand making a better seal....
Thank you.

[kevo]

After giving this car a bloody good rev it stopped and would`nt go again till i poured petrol down the carb
SO-
Right Guys an update really.....Cleaned out breather+No Diffrent,
New coil,
King lead,
New condencer again....
New petrol pump = NO DIFFRENT,
Change Carb again= runs but hesitant and spluttering/popping through exhaust with flames.....
When spluttering -Timing marks all over the place....Then it will run nice and rev as normal....Then back to the spluttering and popping through exhaust...

I`m in desperation now guys before this piece of S**T goes on e-bay...PLEASE.....??????

Edited by kevo on Friday 10th August 19:06

[Cooperman]

What I would do is this:
Change the carb for a completely different one (beg, borrow or steal one). Re-jet to suit your application from the recommendations in Vizard's book.
Change the distributor for a 'Sports Coil' running at 12V (no tthe 9 Volt, if that's what you cussently have. Make sure you carry-over no distributor parts. Have a new dizzy cap and new leads.
Fit a new minifold gasket matched to the inlet manifold.
If you have an alloy inlet manifold, have if tested for hairline cracks. I once had a problem with a manifold which had an almost invisible crack which let in air. We only found it by dye-penetrant inspection (I was in the aircraft industry back then). Ideally change the manifold completely and blank off any servo pipes until you solve the problem. In fact, blank off any vac pipes to carb or manifold - reconnect them one at a time once it's running to isolate any problem there.
I would also check the cylinder pressures both hot and cold, just to be sure it's not something really silly like a slightly burnt-out exhaust valve (although I'm sure you have checked this already).
If you do that and it still won't run, I can only suggest a visit to a diagnostic centre with a rolling road.
Last week I had a problem with a 1061 cc 1986 Mayfair which simply refused to start after a complete re-build. I just changed everything as above and it burst into life. Still don't know what was wrong, but it's fine now.
I hope this helps,

Peter

[kevo]

Thanks Peter......Going to have another go tomorrow....Kevo