View Full Version : Diagnosis please

04-07-04, 07:19 PM
The engine is a 3.5 1984 V8. today after a long hard run :D the following has happened: -:(

The car will not idle, it just dies
whilst i was driving there were large clouds of smoke with a "burnt oil" smell
around the nearside plugs is a lot of oil spilling onto the headers and spread over theplug leads and onto the floor
the car will not now start without full throttle

So what is the problem? :confused: Headgasket? Hole in piston?

Any sugestions gratefully recieved

04-07-04, 08:26 PM
Tony, if there is oil over the plugs, leads, & headers are you sure that the rocker cover has not just worked loose and as there is so much spilt oil around the plug leads are earthing out. If the head gaskets have gone and you are using tin ones I have a pair of new ones you are welcome to. Best of luck and let me know how things are going :o

04-07-04, 08:32 PM
Tony - don't panic. It could be something very simple. Unless it has no water left in it I doubt it is a head gasket.

If you holed a piston you would have a &hit load of gasses coming out of your breathers and dip-stick.

Oil over headers and onto the floor is probably just rocker-box cover gasket or inlet manifold gasket . Nothing too major to worry about - check the hold-down screws on the rocker covers first.

Car refusing to start except on full throttle could just be fuel vaporistaion after a good thrash. Let it all cool down and start diagnosing properly.

This is part of the fun of running a Cobra.

Very difficult to diagnose these things over the 'net. - Get the thing around to Tinks or my place and we will sort it.

Chill out - it's just a pile of metal thing!

04-07-04, 09:24 PM
Ok, rocker cover gasket sounds reasonable, i didn't think of that because of the cloud of smoke but i suppose if the oil is pi$$ing all over the headers it will smoke.
Tomorrow i'll check the rocker gaskets, if they're ok can i assume if it starts normally there is nothing major wrong? If it fails to start where do i start looking next?
Wilf, there were some gasses coming from the breathers whilst i was turning her over and the oil is in a position to have come from the dipstick tube, Mmmmmm

04-07-04, 10:16 PM
Tony - if it continues to trouble you, call Tinka for my number.

05-07-04, 02:03 PM
I think a compression check is in order, that will soon tell you if you've holed a piston, or badly scuffed a bore.
If it won't run without throttle that would indicate that the crankcase pressures are not right, could be a major rocker box leak, or pressure due to a holed piston or other maladies. :(
I hope it's nice and simple.