Engine not firing correctly when hot

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WillsMck
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Engine not firing correctly when hot

Post by WillsMck »

Hi, I have a problem with the 1098cc engine in my minor. She was very lumpy when starting from cold and inevitably cut out when driving out of the garage. I replaced the plugs and that seemed better. However before this and now again when the engine has been running for say 30 mins to 1 hour, there appears to be a great hesitance to pull away in the lower gears when accellerating. If you get enough speed up to go up a gear she seems to run reasonably. However it got much worse just there and was almost not able to get up a fairly small hill in 1st gear. There was a lot of smoke from the exhaust and I would say she was certainly not firing properly. I was expecting a huge backfire but that didn't happen!

I have in the last year changed the following

Plug
Points
Condenser
Dist Cap
Carb refurbished
Ignition Coil replaced
Rotor arm


I have not yet replaced the fuel pump - other than that it's all beyond me.

This is becoming quite frustrating as we are loosing faith in the wee car and as a result are using her less.

Can anyone help?

Thanks and Regards,

Willie
aupickup
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Post by aupickup »

have you tried a compression test, possible head gasket. could also be timing.

do not lose faith, these cars are simple to maintain and work on and when running fine will be better than modern car
minor_hickup
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Post by minor_hickup »

Have you replaced the HT leads, a similar thing happened to me and thats all it was.
bmcecosse
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Post by bmcecosse »

Sounds like very rich mixture -check the choke is going completely off - and check if the piston in the SU can rise and fall easily. With the little damper removed - the piston should fall with a 'clunk' Put some 3 in 1 oil in the damper and try again. Could also be the float valve leaking and allowing the carb to flood. With the engine sitting switched on but not running - does the fuel pump tick away regularly ? It should NOT !
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Chris Morley
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Post by Chris Morley »

I agree - it sounds like you're effectively driving with the choke out. Rather than give up on the mog, tell us where you are and we may be able to recommend a nearby specialist. It's probably easily fixed by someone who knows what they are doing.

I doubt this is the fuel pump - lots of exhaust tends to imply lots of fuel!
Chris
-------------
1969 2-Door daily driver
bmcecosse
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Post by bmcecosse »

Hmmm - I just noticed 'carb refurbished' - who did this ? What did they do ?
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Pyoor_Kate
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Post by Pyoor_Kate »

If it is the choke sticking on, it could be as simple as a sticky choke cable - does the choke cable actually move when you pull out / push in the choke?
Pyoor Kate
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WillsMck
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Post by WillsMck »

Hi, I am based in Glasgow, so any info on recommended specialists would be helpful. I shall get a look at the choke cable etc and have the flot needle checked out. I haven't used the car since 20 August when she last played up.

Thanks for the replies

Wills
rayofleamington
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Post by rayofleamington »

It could also be the plugs getting oily, giving a bad missfire but that doesn't completely fit your description.
I would check to see what colour the plugs are at the same time as doing a compression test (Old compression testers can go for a few quid on ebay and new ones around a tenner if you can't borrow one)
Ray. MMOC#47368. Forum moderator.

Jan 06: The Minor SII Africa adventure: http://www.minor-detour.com
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Jan 07: back from a month thru North Africa (via Timbuktu) in a S3 Landy
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Sept 2010 - finally gave up breaking down in a SII Landy...
where to break down next?
2013... managed to seize my 1275 just by driving it round the block :(
bmcecosse
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Post by bmcecosse »

You say 'Glasgow' - whereabouts ? I may be fairly close to you and will happily have a look at it for you. I am in Stonehouse.
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WillsMck
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Post by WillsMck »

Thanks, and sorry for the delay in replying - I am in Milngavie and would welcome any help with the wee car, as we have got to the stage that we are a bit afraid to use her.
bmcecosse
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Post by bmcecosse »

Hmmm - bit of a haul to 'Milguy' - but if you can get the car to Stonehouse I could look at it. 01698 792376 if you think it worth a go.
But again - who 'refurbished' the carb - it's probably something to do with that. Try taking the air filter out in case it is caked with oil and dirt. Won't hurt to run without for a bit.
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WillsMck
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Post by WillsMck »

It was refurbished by the Classic Car Garage in Rutherglen Glasgow. I think that the air filter was also replaced last year. If we get a spell of dry weather I may give you a call - its just too wet for the wee convertible these days, I am also not too confident that she will make it too far before the problem arises again,

Thanks for your help bmcecosse,

Regards,

willsmck
bmcecosse
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Post by bmcecosse »

Ahhh - i have heard various tales re that garage !!!!! And there was at least one strange ebay sale that involved them too. Can't say too much on here. beware !!!!!!! Sorry I'm so far away - and I rarely pass by your door - but if you can get it to Stonehouse I will gladly do what I can with it. Maybe some other Scottish Minor owners nearer you ? I don't know what happened to the Scottish section webpages - did they fade away ? I can't find them now.
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