motor running rough

[Tony_Whenua]

Been driving the 1200 a12 over the last month and its started coughing when i accelerated (esp when cold) and its been blowing some black smoke.

Thought it was my filter so i cleaned head filter and carb filter.
That didn't do much so i got 4 new spark plugs - old ones were 'black as' and the one closest to radiator was chocker with carbon soot. Also checked all the spark leads and they all get a spark.

Seems to run okay now with the odd cough and still a small amount of smoke (didn't go for long drive, just around corner etc).

Is the fixing of the spark plugs just fixing the secondary problem or is there something else i need to check over?

[torqued]

Check resistance on leads, cap and rotor.

Change thermostat, points, condenser and fuel filter.
What plugs are in there? check the condition of them after a week might pay to go up a heat range on the plug if sooting.

Give a carb throat a good spray with carb clean while motor running hold revs at about 3k RPM

that will give tyou a good base to start diagnostic on

[Tony_Whenua]

Check resistance on leads, cap and rotor.

Change thermostat, points, condenser and fuel filter.
What plugs are in there? check the condition of them after a week might pay to go up a heat range on the plug if sooting.

Give a carb throat a good spray with carb clean while motor running hold revs at about 3k RPM

that will give tyou a good base to start diagnostic on

Thanks for that.
-What am i looking for with thermostat?? that it opens when temp gets warm?? Car never really gets over half way on temp gauge.
-condenser and points located in the distrubutor right?? found this image but dont overly know what im looking at ... http://datsun1200.com/uploads/photos/23635.jpg" onclick="window.open(this.href);return false;. Again how do i test it?? Info says i should replace them every year.
-Willl get a new fuel filter tomorrow, chances are its due for a change.
-Will get 'carb clean' tomorrow too.
-Spark plugs were $8each. cheap NGK ones.


http://www.trademe.co.nz/books/nonficti ... 152977.htm" onclick="window.open(this.href);return false; <- this is a b210 version work/repair manual right? I haven't been able to find a b110 so would this one work for my ute???

Sorry if it seems im stupid. Dont know much about this but im keen to learn. Help greatly appreciated

[dirtyleppa]

replacing points, plugs, leads, condensor, distributor cap, rotor and coil are the 1st things i do when i get a new car. that way you have eliminated those as possible faults. if its still a problem once you have done that, then its time to dig deeper. NGK plugs will be fine for your ute. if you want to check your leads are good, use a multimetre to check there resistance. should be under 15000 ohms if im correct.

if you are one a budget, just replace one part at a time, until you can afford the next. i would hazard a guess that its most likely your points or maybe your coil giving you trouble

[torqued]

Take off the dizzy cap with leads attached using a multi meter I use the rule of 8Komhs of resistance for every 300mm of lead inc cap.
test the leads attached to the cap.

Inspect the cap looking for cracks and pitted cap contacts. they should be clean. you can give them a light rasping with a screwdriver but careful because they can be brittle. (post a clear HD pic if unsure)

What are the Plugs part number? the number on them is the heat range. going up a heat range can help with burn off.

post a pic of your engine bay ill circle where the thermostat is.

remove it. note the temperature stamped on it. boil it in a jug of water use a "thermostat" to check the temp of the water. you should notice the thermostat starting to open before it reaches its temp and fully open at the stamped temp.

Ill proof read this tomorrow, its been a wet afternoon

[classicdat]

How is it starting? If the points are at fault it will be hard to start. Testing points is by eye, initially, are the faces smooth and square. The important thing is the setting, this is the 'points gap', and is best set as degrees of dwell, on a dwell meter with the engine running. They should be set at 49 deg for the best results. Adjusting the points is very precise, and upsets the timing, also as the points go out of tune they upset the timing also, reset timing after setting points. Weak spark can cause your Sootting of plugs and this could be caused by all the things suggested in this thread so far.
Mixture could also cause it, does you choke work, if not then you may be running lean, this can be caused by muck in your carb. An easy fix that can work for this without tearing you carb apart is to remove the air cleaner and its bolt from the carb, run the engine up to about 2500 RPM and seal off the top of the carb with the palm of your hand, just as the engine stumbles remove your hand and let it recover. Don't stress if it dies, it may take a little to start as you will have flooded it, but it shouldn't be to much hassle.

If you replace the points take care to clean the face so the preservative is cleaned off, you want the whole surface to be use-able, not have it arcing off only one point.

Hope this helps, these are great simple wee engines and awesome to work on.

[torqued]

Found these videos regarding points replacement for you.

This one for educational purposes.
http://www.youtube.com/watch?v=7fUbvKgmmQQ" onclick="window.open(this.href);return false;

this one seems like a good how to guide
http://www.youtube.com/watch?v=Y9wZvcr3 ... re=related" onclick="window.open(this.href);return false;

[torqued]

Did you keep your old plugs. found this for your reference
http://www.ngkspark.co.nz/spark-plugs/t ... g-analysis" onclick="window.open(this.href);return false;

[classicdat]

Great information there Adam, would be good to put them on the Tech Forum.

[Tony_Whenua]

I've bought new points and condensor for ute. Does anybody know what size feeler gauge im suppose to be using. YouTube clip says 15 hundreths (0.015 ??).. Is that the right one for a12 engine?

Old point had small pitting so hopefully new ones will help.