Morris 1000 misfiring

[Daphne]

Hi,

I’m a new owner of a lovely 1970 Morris Minor 1000. Currently stored a fair few miles away so not able to take her for a drive often at the moment unfortunately.

The first drive out always proves to be a challenge due to misfires, loss of power/choking/cuts out (also sparks out of the exhaust I’m told!).

I’m assuming it’s because the modern fuel sitting in the tank isn’t what my Morris is used to and just wondering if there’s anything I can do to prevent this and keep her nice and healthy.

Thank you!

Vanessa & Daphne, the Morris Minor

[KeithL]

Vanessa,

Welcome to Morris Minor ownership and to the Forum. Is this your first classic car? If so you will soon learn that they all have their little quirks and idiosyncrasies. Talking to them helps.

Someone who knows what they are talking about will be along soon, but in the meantime whereabouts are you as there may be someone local who could come round and take a look? Also, have you made contact with your local MMOC branch yet as that will provide an opportunity to meet up and talk to other owners in your area?

[simmitc]

Hello Vanessa and welcome. Misfires can be caused by a lot of things, but mostly simple to fix. How adept are you with engines in general and spanners and screwdrivers? Do you have a multimeter for testing electrical things?

1) A couple of questions to help set the scene:
2) Did Daphne behave like this when you tested her before purchase, or is this something new?
3) Has she been serviced or had any other work done to her recently?
4) Before purchase, was she in regular use, or stored in a garage/barn?
5) When she starts, do you use the choke, AND push it in afterwards?
6) "The first drive out" is problematical, but does that mean that she then settles down and works fine for a day or two? How many miles is the first and subsequent drive?

I suggest:

• Check the points gap (15 thou) and reset the static ignition timing.

• Reset all valve clearances to 12-15 thou (opinions vary on the best gap, but anything in that range will be fine.

• Clean and re-gap spark plugs (25 thou) and check that leasd are on in correct order (1-3-4-2, anti-clockwise around distributor

• Take the lid off the float chamber and check for crud/muck in the bottom.

• Make sure that the jet on the carb does return properly when the choke is pushed in.

• Check compression on all cylinders (report readings here for comment).

If there is still a problem, then we can look at changing the condenser, gap and rotor arm; but do not just change things for the sake of it, we'll work through methodically.

If any of that doesn't make sense, don;t worry, just ask. All the procedures are detailed in the manual, but if yo don;t have one, then we can explain in more detail here.

She will be OK

[cyrus]

It could be due to someone having fitted a cheap condenser as there are many cheaply made ignition components on the market at the moment. They last a few hundred miles and then cause lots of misfires/backfiring, stuttering and so on. Don't ask me how I know.....
Worth changing out for a known decent component and if that's not the problem good to carry a spare anyway.

[mobylette]

And this is the place to purchase good quality ignition components:

http://www.distributordoctor.com/

[Daphne]

Hi everyone, wow, fabulous set of responses!

Daphne was very well looked after before I bought her. Stored in a garage and driven out weekly. It’s just the first couple of miles where she coughs and loses all power etc. I tend to drive her out, then pull up once she ‘stops working’ and when I start her up again she’s fine. Perhaps she just needs more regular trips out?

I will check each response and try and narrow the problem down. Thanks for everyone’s help so far! Thankfully my husband is pretty mechanically minded as he has vintage tractors which take lots of restoring!

Vanessa & Daphne

[Daphne]

Here’s Daphne in the middle of a wash and polish

[simmitc]

She looks like a lovely car. Headlamp peaks or "leg-cutters" are something else on which opinions are divided and can be quite strongly held and expressed on both sides of the argument.

Poor quality condensers tend to start OK and then breakdown as they get warm, whereas, if I understand correctly, Daphne starts roughly and then settles down and works fine. Therefore I'm wondering about correct use of the choke or perhaps condensation in the distributor cap. There could also be a valve sticking when cold and freeing off when warm, but the engine would not cut out, just start to run better as it got warm. Work through the earlier list, and we'll see where we go.

[oliver90owner]

Hi everyone, wow, fabulous set of responses!

Daphne was very well looked after before I bought her. Stored in a garage and driven out weekly. It’s just the first couple of miles where she coughs and loses all power etc. I tend to drive her out, then pull up once she ‘stops working’ and when I start her up again she’s fine. Perhaps she just needs more regular trips out?

I will check each response and try and narrow the problem down. Thanks for everyone’s help so far! Thankfully my husband is pretty mechanically minded as he has vintage tractors which take lots of restoring!

Vanessa & Daphne

Might I suggest asking your husband? He is likely to sort it out in double-quick time. What make of tractors does he prefer/restore? (he may well guess the make I prefer)

My first thought was that of resetting the valve clearances. Ignition is easy to check - is the spark strong and blue or weak and yellow? If a strong blue spark at all plugs, there is little wrong (basically) with the ignition system. As previous, there may be condensation in the distributor cap, or the plug leads/caps may be leaking energy. A new set of plugs would likely not go amiss!