Does my V8 need a rebuild?

[dicko]

Hi

I recently bought a P5b coupe which although in lovely condition has seen very limited use in the last 10 years.

I have already rebuilt the fuel pump as that caused me to breakdown. When I removed it a load of oil came out of the pump?? Could that be an indication of engine problems?

When the car is on full choke the oil pressure gauge moves very slightly and the previous owner told me that it was faulty. When the car is hot it goes to zero.
Also, when the car is hot the oil light does flicker when on tickover which leads me to suspect something more sinister. A faulty gauge and pressure light too - unlikely I think.

I have changed the oil and replaced the rear breather but there is no change. When I took the car out yesterday things got worse. After about 20 miles under acceleration the car has developed a noise similar to pinking from what seems to be the top end. When I listened to the car on tickover it seems OK - no rumbling or knocking and only only the very slightest tappet noise on one side. Strangely the car uses no oil and the new oil is still nice and clean.

Any ideas? Help please.

By the way I will be taking the car to get the pressure checked just to rule out the faulty gauge theory and someone did suggest clearing out the breathing system but I am not sure what this entails.

Dicko

[Phil Nottingham]

The pressure gauges (actually the sender) are not very accurate and should be regarded as decorative items only. The only way is to check with a known external gauge. The sender diaphragm hardens with age so s/h ones will probably be the same. I converted to mechanical Bourden tube type using the same dial face Not certain whether new ones can be had either.


The V8's run at low pressure(but high volume) anyway (40lbs max) and with a worn engine anything down to 25 lbs hot will be OK as is filckering of the oil light when hot and with low idle (s/b 650 rpm). The handbook even mentions this. A sticking pressure relief valve in the pump can also give low pressure.

The senders can fail also but these are cheap (Land Rover dealer will supply many engine parts)

Nothing wriong with the oil in the pump and in fact a worn seal which is not in pump kits can actually pump out oil from the engine!

Not sure about the noise if your are certain its not pinking (retard up TDC if necessary) could be a little end or rings. Tappets/worn cam is usually vey much more louder.

Does the engine run and pull otherwise OK as you may be able to run this for many miles before rebuild. Low miles in these engines does not mean it's ready though. Check the compressions are all even.

Dirty breathers can cause oil leaks - clean or replace the two Grey cannsiters leading from the rocker covers to carbs. Also check the tubes and coonections are clean as they can easily clog up with oil residue.

These engines are very very prone to Black Sludge if not used or the oil is not changed frequently (either by miles or time)

[dicko]

Thanks Phil - I will carry on my investigation - Dicko

[Phil Nottingham]

Please let us know how you go on - but do not panic and enjoy the car for what it is - tell us more about it and you. Whereabouts are you

[dicko]

Hi Phil,

I am based in Suffolk not too far from David Green. I rent a barn with an inspection pit so there is no excuse for not getting my hands dirty.

As I mentioned the P5 has seen little use in the last 10yrs and needs some general fettling. On the positive side it has always been MOT'd and had the necessary work done it it failed.

Although I changed the oil and filter I did not use any sort of flush. Is it a good idea? I wondered if it would clear any sludge but I have heard people saying these products may cause more harm than good!! Also, would you recommend flushing the cooling system? Someone said 'clear out the breather system', but what does this entail?

I just want to do everything I can to bring the car to optimal condition and if it is still not right so be it!!

I just really want to build some confidence in the car as currently after the fuel pump incident I am reluctant to travel any great distance.

I noticed that the temp gauge takes ages (10 miles) to get to the middle of the gauge but then sits there. Do you think a new thermostat may be in order or are we looking at an iffy gauge?

Finally the rev counter jumps wildly - a common fault I know - but could this be attributed to the fact that there is a Lumenition fitted?

Regards

Dicko

[Deleted]

I fitted a Lumenition ignition system to my P5B coupe and the revcounter was fine.

I would check all connections are secure and clean, otherwise an overhaul / check of the tachometer/revcounter may be needed.

Try John Ostick 01535-662701, ask him for an estimate first.
Very reasonable prices and very fast turnaround when I last had occasion to use him.

Cheers.

[dicko]

Thanks Freddy -

I will check the connections etc.

Dicko

[Phil Nottingham]

I mentioned how to clear the breather system in my first response.

As to engine flushing this can be problematical it really depends how bad its got as if it badly encrusted flushing can cause more problems by loosening flakes of carbon/crud which block oilways.

Remove a rocker cover to see how bad it is - high detergent deisel oil is an option to lengthen the life of a tired engine. Have you sorted the oil pressure yet?


Its a very good idea to flush the system and renew the stat. Your gauge may be oK - if there are no signs of overheating. This weather should test it!

PS

Have confidence we have been all over the place in our P5's for years eg Southern Ireland and have just got back from touiring SW Scotland ;D

[Deleted]

I agree with Phil.
My water temp. gauge usually sits at about 1/3 of the way across the dial but in this weather it sits around 1/2 way across. If it gets much higher than that, then my electric fan cuts in.

Cheers

Ady