Mk7 much help needed please!

Got the mk7 head back AGAIN , all seems to be fine . Checked the clearances , pretty close to good . All valves survived leakdown tests . Fitted the head , factory spec compressions 110 , good for a 7 to 1 engine . That’s when my troubles started ! Made up a new set of plug leads , it wouldn’t start . It wouldn’t even try to start . Convinced It was timing , I changed a few things ,. Zilch . Thing is , after endless cranking the plugs are dry . Not a hint of petrol . How can this be ? I have a good spark , both the pumps are working well , float chambers are full . I blew out the carbs with compressed air , still nothing . One thing I noticed , the book says when no. 6 is at 5 degrees btdc the rotor arm points foreward toward no. 6 . Mine is pointing to about 10 o’clock , so I assembled the leads in the order following 6 , ie 2, 4 1, 5 ,3 is that right ? I hadn’t removed the dizzy , but I did so just to know if there is anything that can be changed . As far as I can see , it can only go in one way anyway . So Good spark , but no petrol , even after a minutes continuous cranking . And I’m not convinced about the timing . Help please .

Just double check that the cams are on the correct side, taking into account the troubles you have had with the rebuilds don’t assume they have placed the intake cam on the intake side.

To check the timing, mark the crankshaft pulley and use an old fashioned type of strobe, the type which goes in series with a plug lead. You can then see how far out things are. You don’t have to start the engine to do this. Just take out the plugs and crank it. You may need to lengthen the leads on the strobe. Use the lead from the front cylinder, (no6). You can connect one strobe lead directly to the appropriate connection on the distributor and simply earth the other one.

Hi Kenny. First time reading any of your posts so do not know how familiar you are with Jags so will throw this out - on the XK engine #1 cylinder is at the back of the engine and counts from there, not the front like other cars. Just a thought.

Hi Robin , they had marked them , in and ex , but how would I know if they are wrong ?

Yes , I did know that , thanks Brian .

Hi mate , never used one of those . But why the dry plugs ?

Cams should have distinct part numbers cast in.

Maybe the intake (suction) is done throgh exhaust valves, while the exhaust stroke is … blowing back through carbs … ?

Turn the engine to TDC firing on #6 (front cylinder) and open the oil filler or take off one of the cam covers, the cam lobes should be pointing away from each other.

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I would start by doing something easy, which is spray an ether based aerosol product into the carb throats while the engine is rotated by pressing the remote starter solenoid button. If it wants to start, you may have a fuel supply issue

then triple check your spark plug wiring order

If not, I agree you will have to go through the process of verifying timing issues, starting with cam ID, then timing position with the cams, timing pointer, and distributor all lining up correctly

Done that , no response . Picture shows position of exhaust cam when no.6 ( front ) piston is spot on tdc is this correct ?.

As long as the tach drive has not been removed if it is on the left side of the engine the cams are likely correct.

Makes sense , thanks

If the cam lobe is pointing into the valley then no I don’t believe it is correct.

It’s pointing away from the valley .

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Ok must be the angle of the photo.

Yeh , the endoscope is through the oil filler looking forward , the no. 6 exhaust bucket is on the right , partially hidden by the shaft .

I think I am misunderstanding, I’ll put the question another way, is the exhaust cam lobe you are showing pointing to the inlet cam or away from it?

It’s pointing away from it . All good then ?