SLROC Forum

Anyone in the Edinburgh area with an ear for a V8?

Gutless, sounds like its missing, have checked the obvious and normal things, decent spark, vacuum leak.

Sounds pretty bad.

Any assistance welcome.

coop

I would if I still lived there! Has it just started? Hot cold or both? EFI or carb?

I would start with the basics, dizzy cap, rotor arm and leads from SimonBBC. Its the only stuff available now thats proved to be reliable, LR genuine doesnt have good rotor arms any more. NGK plugs are also advised, and if the existing ones are over a year old they will def need changing (not everyone realises plugs go off after about 12months). Over 80% of the time running problems are fxed by fitting the correct quality ignition parts!

If the engine has just started doing this and is EFI, find yourself a fuel pressure gauge and check the pump isnt failing.

With a bit more info I can suggest more things to check.

simonBBC?

Does it hot & cold, getting progressively worse, its an EFi that has been run on gas for a few years coming up to 200k on the clock.

Had it a quick check on a crypton and there was a cylinder down, number 6, will compression check at the weekend. No emulsion in the oil and no excessive crankcase pressure that is evident with the oil filler off.

I will replace all electrical bits and take it from there.

Camshaft is a known problem if the quality ign parts dont cure it. not a bad job to do if you can get it inside out of the cold. mornings work last time I did one.

Second getting a pressure gauge on the fuel rail. Mine was doing something similar and it turned out the fuel pressure regulator was goosed - plumbed the gauge into the cab and pressure fell through the floor whenever it hesitated/misfired.

Use quality parts for plugs, dizzy cap and rotor arm. Cheap alternatives just won't do when running on lpg especially. Start by changing the plugs. Also worth testing the output of the coil - I can't remember the details of this but sure you can find it on tinternet

NGK plugs are the best. My preference is for BP5E which are v-grooved and rated hotter than others.

If memory serves me correctly, for a RRC the spec'd NGK plugs are BPR5ES, I ran mine on BPR6ES's for almost 200,000m with no problems (on LPG)
I'll second previous comments re good quality ignition parts and fuel pressure.

V8 cams are bad for wearing the lobes on the back cyls due to poor oil feed to that area but it is amazing how bad it can be before you notice it.... you've always got a spare cylinder or 2  unlike a 4cyl....

If you need a hand just shout as I'm out beside Edinburgh Airport

Bob

This "sparked" my interest.....sorry. So I had a wee read of the NGK website and e-learning program:

http://www.ngk-elearning.com/

I've got the hot cold thing round the wrong way. The number in the spark plug code refers to the running temp of the plug, due to its ability to dissipate heat back to the head of the engine. The higher the number, the colder the plug runs. You want the plug to be running in the optimum temp range to avoid running cold causing fouling, or running hot also causing damage. So bacause lpg burns a little hotter than petrol you want to move up one number to compensate.  BP6E therefore look the best to me as they will run cooler than BP5E. They're still v-grooved, which forces the spark to occur at the outer edge of the electrode, which means the air/gas mixture can get at it easier and is more likely to ignite than standard flat type electrode plugs.

Have swapped components from a running vehicle one at a time and no change, checked on crypton and good spark at all cylinders, still only running on about 6 and a half.

Does anyone have a definitive method of checking the cam, in situ, before I pull the thing to pieces outdoors in our current balmy early spring weather?

All suggestions welcome.

coop

Warm the engine, rev hard and lift off (easier with a helper), listen to the exhaust on rundown if its lumpy and uneven with odd pops and bangs the cam is worn.
I would recommend a piper replacement (the 255 is very mild) as the value against genuine is better. Use only genuine followers though there has been faults with every other suppliers I've seen. New timing gears and chain are a must too

Agree with above. you will have to remove the inlet manifold and valley gasket and take a look, its the only way to be sure. it does sound more like a cam problem now after all you have done.

Coughs and splutters like Wiltshireman giving away a prized pig.

Much thanks for the advice I will be investing in a cam kit from somewhere reputable . . . .

coop