Engine problems ?

Steve C

Member
Hi any help on my problems would be very helpful, car is rover p6 2000 tc, generally speaking the car runs well, however just lately when starting from cold it wants to initially idle at about 1500 rpm, this only lasts for a few minuets till it has warmed up slightly then the revs will drop to a normal steady 800. and starts after the initial start from cold are fine. it feels just like a more modern car with a auto choke.

recent work on car includes complete overhaul of carbs, valves, and valve gaps, and new electronic dizzy.

on checking the plugs i was quite surprised at the colour ( red insulators, see pictures) the exhaust is a nice grey/ black colour with no sooty deposits.

car starts, drives nicely with no pinking, or running on, when i set the ignition timing at 6 btdc it was not happy, by advancing it about 1cem past the 6 point it runs much better, sorry about a bit of rambling on but its hard to explain.
 

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The fast idle has changed since the carb and valve work yes? My guess is the fast idle screws might be a little too far in. I would back those out and see if the idle speed drops a bit while the idle stays smooth from the enriched mixture. IIRC fast idle should be 1200rpm, so 1500 isn’t too far away. (someone should confirm that perhaps as I’m a little rusty).
 
thanks for the reply, the fast idle has developed recently not straight after any engine work, fast idle screws are backed off well clear of the stops, my main concern is the colour of the plugs.
regards Steve.
 
Are you using any lead substitute in your fuel? That can give a reddish-brownish colour to the plugs.

I would double check your mixture as it could be a touch lean.
 
Thanks, yes i did add a fuel additive before Christmas, but surly any discolouration of the plugs would have worn off by now, and seeing how clean my exhaust is, I will take your advice and check the mixture.
many thanks Steve.
 
I had my 2000 TC rolling road-tuned at Northampton Motorsport a couple of weeks ago, and when we took the plugs out we saw that the electrode insulators were red. Properly red, not red-brown. NM asked if I had been using an additive but I hadn't. Fuel was Shell V-power. I had never seen red plugs before, and NM were baffled. Maybe there's something in the V-power blend that causes it.
 
Thanks for all the above advice, but I still have concerns about the colour of my plugs,

I have replaced my brick red plugs for a new set of NGK BP7ES, and have covered about 40 miles on duel roads at 60 /70 MPH and on checking the plugs am rather shocked at the colour, -- the insulators are bright white and 100% clean, you would think they had never even been fitted in an engine.

The car drives as good as it has ever done, the ignition is well advanced ( runs rough at 6BTDC) carbs tuned and balanced by ear, nice even sound from exhaust, and nice colour at tail pipe, I did en rich the carbs half a turn but it made no difference to plug colour, could the ignition be to far advanced to cause the plug colour.

Any help on this would be great

Regards Steve.
 
Many thanks for sending the video, lots of good info on it, I now realise my plugs are not far off.

regards Steve.
 
Not everyone will agree with the content, but it seemed sensible to me. I have seen countless methods of reading plugs over the last 50+ years I have been playing with engines, if the analysis in this video is correct then it would be a great asset.
I only just removed all my plugs in my 3.9 last week to compression test the motor ( circa 200 psi all pots ) if I had a spare I would have opened up a plug to look at the insulator, I will certainly do so next time.
 
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