oil pump???

[DAVE39V8]

Hi all i'm Dave from Essex and a new member..
I have a R/R Classic 3.9 Vogue SE on LPG(when it works,but thats another story).
I've recently been thro the muddy stuff and loved it..
I'm experiencing some running probs. There is a tapping noise from the lower drivers side of the eng with gentle revs.
After afew mintues driving the oil light flickers on it runs very lumpy(as if its running out of fuel) the cuts out.
Leave it afew seconds or so and it starts ok but happens again minutes later..
I'm not sure but could this be the oil pump?
The rev counter doesn't work straight away but when it does the alternator makes a dry bearing noise..
Are the two linked in some way?
Hope someone can help me and point me in the right direction..PLEEEASE!    

[Greybeard]

Hi Dave and welcome.
Have you checked the oil level, if yes was it ok ?
The alternator could well have a dry bearing as you suggest, mine also does the lazy rev counter sometimes although i dont experience the noise.
Has all this occurred since off roading ?
How long have you been hearing this noise from the engine ?
Does the engine need to be warm to create these symptoms ?
When it makes the noise , is that when the light comes on ?
Does the oil light extinguish as soon as the engine is running ?

Cheers
Steve

[DAVE39V8]

Hi Steve,
I've just had my exhaust altered(again,was too loud in the morning,it were straight through)and I think I have sussed out the tapping/rattling..It seems to be a calapsed cat on the drivers side.
Although the cutting out still remains..The oil light comes on but I rev it,it goes out and runs like it got a miss..Turn it off,few seconds starts ok..
Oil level ok,although I might change to 20/50..
Alternator definately sounds like a bearing.So that next on the list..

Regards
Dave :D

[FBF]

could the oil light issue be related to gunked ports? maybe try an engine flush.  the previous owners may have lacked in oil changeing skills. and a sludge build up could be holding all the oil at the top of the lump causing the oil light to show..

just an idea.

[Greybeard]

Just a tip for us older land rover owners, that is if no one else has posted this, Adsa and Morrisons both do 20/50 motor oil at around £4.50 for 5 litres. I have been running it now for 12 months no probs. Change every 3000 miles and filter every 6000. Good saving for people with engines designed for 20/50.

[Greybeard]

Also forgot to mention, if you are running on LPG when you have the vehicle tested, you can take your cats off. :-)

[DAVE39V8]

:D  think i gonna give it a change of oil back to 20/50 flushing it out first..getting cat replaced 2mrw..mine is on lpg but it got a problem at mo(another one to the list lol). :lol:

[Range Rover Blues]

Cheap 20/50 can cause problems, firstly it doesn't hold it's viscosity, not even for 3000 miles, also it can cause problems with the hydraulic tappets, something I wasn't awaye of myself untill recently.  I use the Lucas stuff from E-Bay, it's £25 for 9 1/2 litres but contains a decent oil stabiliser too.

BTW, the rev counter/alternator thing, check the belt isn't slipping on both the alternator and PAS pump.

[drmike]

Surely the oil light coming on when it stumbles is just saying there's not enough pressure while the engine isn't running right. Not a cause but a symptom?

I'd be looking at the HT side to start with (but that's because I'm not familiar with EFI problems). People always ask is it hot wire or flapper and you could do worse than search the forum for references to those entries.

The oil can affect the tappets both the amount, the viscocity (my money on Morris 20/50) and the flow (which is the pump). I can't see the oil causing it to cut out ot falter. Run rough yes but falter like you've described I would think is unlikley.

The HT can do this though. Check the leads are OK and nothing was shaken loose while off road maybe?

Mike

[Greybeard]

Cheap 20/50 can cause problems, firstly it doesn't hold it's viscosity, not even for 3000 miles, also it can cause problems with the hydraulic tappets, something I wasn't awaye of myself untill recently.  I use the Lucas stuff from E-Bay, it's £25 for 9 1/2 litres but contains a decent oil stabiliser too.

.

Surely ( i know, dont call me surely ) if these cheap oils had the problems you describe, then they would have law suits going from one or two people.
Used to deal with an oil test facility at BP that took brand new engines and ran them for several hundred hours simulation on a test bed, then stripped them to see what wear had occurred. They were actually altering the blend before each test to see which gave best results. The engineer actually told me that even the cheapest oil was good enough for general running on most engines, but he would recommend a high quality oil for high performance / racing engines.  

Take from that what you will, my friend runs his tuned V12 Jaguar on Total Synthetic at £25 per litre and it takes 17 litres. Ouch. Same oil used in the racing V12's and this car only covers about a 1000 miles a year but gets a full service at the start of the year before it turns a wheel. If only we all had that kind of money or the wife to let us spend it :-)

[Sooty]

Don't know if this is any help but on my 3.5 carbed Discovery 1990 the oil pressure switch also triggers a relay in the near side foot well that cuts out the ignition when the oil pressure gets low (the ignition switch bypasses it to allow it to start with no pressure).
I assume this is to prevent the engine from being run with no oil pressure.
I am not sure if this is fitted to the Range Rover of the same vintage but if it is then a momentary drop in pressure may well cause it to miss fire.
This could and I emphasize the work could be all down to a faulty pressure switch, replace it, they are not expensive.

[DAVE39V8]

i had heard of  a safety device like that...the light is coming on more regular but goes out when revs increased alittle..will change oil pressure switch..changed cat today alternator next..anyone got one lol...yle10100 100amp... :?:  :)  :)  :)

[Range Rover Blues]

Cheap 20/50 can cause problems, firstly it doesn't hold it's viscosity, not even for 3000 miles, also it can cause problems with the hydraulic tappets, something I wasn't awaye of myself untill recently.  I use the Lucas stuff from E-Bay, it's £25 for 9 1/2 litres but contains a decent oil stabiliser too.

.

Surely ( i know, dont call me surely ) if these cheap oils had the problems you describe, then they would have law suits going from one or two people.
Used to deal with an oil test facility at BP that took brand new engines and ran them for several hundred hours simulation on a test bed, then stripped them to see what wear had occurred. They were actually altering the blend before each test to see which gave best results. The engineer actually told me that even the cheapest oil was good enough for general running on most engines, but he would recommend a high quality oil for high performance / racing engines.  

Take from that what you will, my friend runs his tuned V12 Jaguar on Total Synthetic at £25 per litre and it takes 17 litres. Ouch. Same oil used in the racing V12's and this car only covers about a 1000 miles a year but gets a full service at the start of the year before it turns a wheel. If only we all had that kind of money or the wife to let us spend it :-)

Knowing how much it's going to cost trying to get £14,000 back for our crappy caravan I don't think many people would bother suing an oil company for a the chance of a £500 pay out, besides, how can you prove just when the damage was done?


Oil is horses for courses,  mate used to work for a large MG specialist, had a guy came in with an MGB but also had a XJ220.  Raved about the fully synthetic oil,how marvelous, going to run the MG on it when it's finished.

Finished it soon was, new engine within 3 months.

Old engines (even when rebuilt) like it slow and thick.  Once an engine is warm it would run on custard as a lubricant, it's cold starts that show the quality in that respect.  the problem Eyore put me wise to was that cheapo oils froth in the hydraulic lifters, which is why I like the Lucas oil with the stabiliser in it.

P.S. I kow a little bit about engine testing too

[Greybeard]

I have built a few useful engines myself, car and bike and would never suggest using anything but " Proper Oil " in an emgine like that, but as i said earlier in the post, i am referring to the older engine such as the Rover V8 that when designed, would have been using the technology of the time oil wise. This would be of a similar quality to the cheaper oil i mentioned. I am not trying to preach to the converted but merely offering a suggestion that fellow LR owners of older machinery may be interested in changing oil at £5 a time and not £25 a time as long as they change it a little more often.

We all have our views on what works and what doesnt, one mans meat and all that, up to the individual to make that choice, be it informed or otherwise.

[MuddyMike]

Your engine does have a low oil pressure cut out, so that could be causing the bad running. My advise is, add a quart of ATF to the oil and run gently for about half an hour. This will give a good flush. Change oil and filter whilst still hot. Use a decent 20/50 like Duckhams. If the problem persists you need an oil pump re-con, not that big a job but can get expensive if the front cover is badly worn.

Going back to the bad running and LPG problems. How many miles has the engine done on the current camshaft?

Mike

[DAVE39V8]

mileage is about 160,000..not sure if original cam...off the road at mo due to alternator housing broken at bottom rear mounting..must of been due to the bearings..also killed my fan belt..ripped it to shreads  the running lumpy hadn't done it for afew days but did notice oil light flicker and come on..went out when revved.. :?

[MuddyMike]

I asked about the cam because depending on how reg the oil changes have been they only last about 60,000 in a Rover V8, and a worn cam causes all sorts of bad running problems. No easy way to tell without having the cam out. Its not a big or expensive job and whilst doing it the oil pump should be replaced as well.

Mike

[Range Rover Blues]

I have built a few useful engines myself, car and bike and would never suggest using anything but " Proper Oil " in an emgine like that, but as i said earlier in the post, i am referring to the older engine such as the Rover V8 that when designed, would have been using the technology of the time oil wise. This would be of a similar quality to the cheaper oil i mentioned. .

Don't confuse the technology of 80's oils with the cheap tat available today.

Imagine your engine was built to run on bitter.  Now all you can buy is Lager, buying cheap lager won't make it bitter.

It's got a lot to do with friction modifiers added to the oil, more modern engines require a different kind of protection due to the thinner oils and the higher temps/speeds they run at.

[Greybeard]

i said earlier in the post, i am referring to the older engine such as the Rover V8 that when designed, would have been using the technology of the time oil wise. This would be of a similar quality to the cheaper oil i mentioned. .

Don't confuse the technology of 80's oils with the cheap tat available today.
,

The engines i have referred to in a previous post were designed in the 50's not the 80's. Oil technology wasnt long past straight grade oil.

At the end of the day, i have my choice you have yours. I know when i would use this cheap oil and when not. If i was entering a competition or the possibility of hard use, then i would use probably Valvoline. For normal running the cheap stuff. My choice, my engine. Merely a suggestion not a point scoring issue and maybe one that could save money, if users wished to do so.

[Range Rover Blues]

Look I'm not for getting into an arguament here, you use whatever oil you choose, your choice.  But when a fellow member asks for advice that's a different matter.  My DEGREE is in mechanical engineering and automotive design, I was sponsored by and worked for Ford Motor Company as a develoment engineer.  More recently I was techical adviser to the SEOC.  I know a thing or two about engines and I know a thing or two about oils.

I DON'T BUY CHEAP TAT, because I know it's cheap tat.  I buy a branded 20/w50 from a reputable company at a competitive price, then as you suggest I change it regularly, as soon as it's gone brown in fact as mileage is very subjective and when you off-road a lot it's engine hours, not miles that count.

That's my advice, end of.