I think i have a severe problem....
Was driving to work when the radiator blew, it also took the head gasket with it.
Have changed head gasket, radiator and thermostat housing.
When i started it up , it sounds as if its only firing on 3 cylinders.
Have checked all the HT leads and injectors and are all working fine.
Do i need a new head?
Any ideas?
Thanks in advance
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Logically, if one cylinder is refusing to fire then there are five possibilities:
1. No fuel.
2. No spark.
3. No fuel, no spark.
4. Fuel & spark present, but their respective timing is off.
5. Insufficient compression for the mixture to ignite.
Check that the plugs are all sparking?
Double-check that you replaced all the valve components correctly?
Did you put new valves in? One may be stuck.
Is the valve / spark timing correct? Were the camshaft and cam followers put back together correctly?
Compression testing each cylinder might tell you more.
After you've compression tested normally, try testing each cylinder without cutting the fuel supply first. Messy I know, but if upon unscrewing the gauge from a particular cylinder the head of the gauge is dry, then you know that cylinder isn't getting any fuel.
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Did you replace the plugs??.If not I would go for that first
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Steve
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Have now done a compression test and chamber 2 has hardly any compression to it at all.
Am i right in saying that in this case i may as well just go and get another head?
Thanks in advance
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Have just been offered a new head from an escort 3i. i know the inlet manifold is different but it comes with a set of twin 45 webers.
Am now wondering is it an easy job to do this and remove the electric fuel pump and replace with a mechanical one.
Have been told that i can just make the wiring redundant and run a pipe to the tank and have the mechanical pump in the engine bay
Thanks in advance for any help
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Apart from finding out why you have loss of compression.I would not replace without inspecting old head first..You may be wasting your time.Ie the lost compression may be caused by damaged valve/or piston ring failure/hole in piston.You need to find out why before deciding on replacement.
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Steve
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I'm gonna get a compressor and push air into each chamber to check for any leaks in the head to rule out a damaged head.
could loss of compression be caused by a warped head?
I have the other head and webers free of charge so its a back up just in case.
Thank You
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When you rotated the crank to aligh the sprockets I suspect you may have clipped and bend a valve, thus the loss of compression. Regards
Peter
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Am now wondering is it an easy job to do this and remove the electric fuel pump and replace with a mechanical one.
Mechanical one should alread by attached to 3i head near the top right. Presumably, a pipe is already feeding the Webers so you'll just have to run the pipe from tank to the pump.
Have been told that i can just make the wiring redundant and run a pipe to the tank and have the mechanical pump in the engine bay
The wiring for the injection system is probably mixed up with that for the ignition system, so there will be a coolant sensor on the inlet manifold which will affect the ignition timing if you remove it. You might get away with a plain old resistor of the right value in its place. Also, going from fuel injection to hefty carbs with increase emissions, so could fail an MoT. You might have to inform your insurance company also, as twin Weber 45s is quite a modification.
The fuel pump will have to be bypassed somehow. Have a look at www.vehicle-wiring-products.co.uk/VWPweb2000/hoses...l for hoses and fittings.
My advice: give the head back. A bent valve may be hassle but it's less hassle than VOSA and Insurance.
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