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Low oil pressure/metal in oil

8K views 14 replies 6 participants last post by  Wraithman 
#1 · (Edited)
So, I have used my car about 10k miles in 10 years, the last 4 years as my only car, year round.

Car has total of 35k original miles.

It has never given a bit of trouble except the oil light has always come on at hot idle in drive.

For about 8 years this didn't bother me. Whenever I saw the light I gave a tiny bit of gas to slightly raise the idle until the light went out. (or if it was really stubborn, I would put it in neutral with a/c on, which did the same). But usually just a slight touch on the gas would put the light out, leaving it in drive.

2 years ago I saw for the first time, metal shavings on the oil dipstick just routinely checking the oil. Tiny tiny bits of metal in the oil, not shavings per se, but more like I was looking at metallic grey paint, but the metal flakes were even smaller than they are in metallic paint. Barely visible but visible. This scared me.

I took the oil all out, took the filter apart, (the old filter style with 7 bits and pieces to assemble) and realized that someone years ago had put the filter in without one of the bits. I forget which. I think it was missing the cone shaped gasket that goes on the spring.

I saw lots of metal dust in the filter can. Cleaned it out, put new filter, new oil, hoped this wouldn't happen anymore.

Well, after about 1,000 miles I see more metal on the stick. Did the oil change and filter again. This has gone on 3 times for 3k miles. Plus I have to assume that it was happening during the first 8k miles I used the car, I just was not looking carefully for metal filings.

But now the oil light is a little more readily able to come on and I have to put the gas on a little more, to make it go off. (now, in hot traffic, at a red light, I must raise the idle to 800 or 900 to make the light go off.). Clearly it is getting worse.

I have started changing oil and filter every 500 miles, and will switch to a SSii oil filter pedestal to make that easier. I thought maybe the ssii oil filter might be more effective straining out metal. maybe that is not true, any ideas? One interesting thing is that I will use genuine Bentley oil filters, because I checked the specs of the oil filters that interchange with that, and they all have vastly different specs. Some have blowoff valves at 15psi, some 30psi, some 40psi, they can not all be correct!!!! I believe the oil pump itself has a blowoff valve at 40psi, so if you also had a filter with that same pressure valve, that would mean your oil pump could quit serving oil before the filter bypassed. VERY VERY BAD!!! A bypass of 15psi would likely also be bad, as high rpm might demand more than 15psi to the mains.

I figure that I have 3 choices. (I won't decide which choice until I speak with 2 or 3 real RR mechanics)

Choice #1 (my favourite choice)
Get all new main and rod bearings, and a new oil pump, and put all these in myself. Engine in situ. (Rod bearings as usual, and For main bearings, I will roll the main bearings in place with Crank in situ, as is done in diesel ships where the crankshaft weighs 200 tonnes).

Choice #1 will cost about $1700 in parts, and special tools. (2 RR spanners for crank nuts, and an engine hoist)

Choice #2 Order a rebuilt engine from Florida, for $7k (plus $1500 core charge + shipping, and I will not send back my core). I would save my core engine, because it shares the chassis number and the car is a ragtop of some value although it falls about $400,000 behind it's competition, the 280se 3.5, which not long ago had same value as the RR.

Choice #3 Have a mechanic rebuild what is there. This will cost about $30k, and I can't imagine I would do it.



Does anyone have any opinions? This car works for a living. It has been my only transport for many years and needs to continue as such. I do not ever intend to sell it. It has been the most reliable car I have ever owned. Has never FTP in 10 yrs. Still drives like a new car, even with almost no oil pressure and metal in the oil.

IF I did decide to do choice #2, and use the cheap rebuilt engine, I would save my own engine and someday rebuild it myself (the correct and thorough way, if the block is not ruined) and put it back in. I can not do that now because I have no shop, and no garage. The repair will be done in a friends driveway or a rented garage if I can find one.


And I have a couple questions...

1. Are these shavings likely just bearings wearing out on account of almost no oil pressure at idle and low pressure other times? Or is the cam and lifters coming apart too?

2. What about the cam? There are no bearings at all there...
My thinking is, if it still runs like new after 10k miles of this, with near nil pressure at idle, etc, the situation can only be improved by all new mains and big end rod bearings, and new pump. I was hoping, if some damage came already to the cam or lifters, it couldn't be too bad now given the motor is dead silent and has full power. and that damage would stop occurring once my new pump and bearings were in they could only raise pressure.

3. Since the cause is essentially a mystery, what are the odds that the original owner or his driver overheated it bad and dimensionally messed up the block? Would new bearings even fit without shimming the mains?

Another idea was to use a used motor but unless there was an easy way to put in a motor from the late 1980s or newer I won't be interested in that. It is my only car. Any used shadow i motor has 50 year old liner seals, and if the car is so bad they are selling the motor, it probably was not a well looked after motor. Wish someone had a shadow that was hit in rear with a good motor I could buy...


Thanks folks.

The shadow knows...


.
 
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#2 ·
I am sorry I am so long winded please forgive me. I can't seem to shorten it.



I guess a follow up question is, if I was going to use choice number 2, and get an inexpensive (read $10k) rebuilt engine, perhaps I should avoid that Ft. Lauderdale dealer and get a rebuilt unit from a place I trust (Flying spares). that will cost a little bit more. I guess I will see what the sea freight and customs brokerage would cost on a motor from Flying spares. (unfortunately I live in the USA and it is long way from England)

So the Flying Spares motor is $9100 plus $1300 core =$9400 plus sea freight to NYC port

The Florida place charges $6750 plus $1500 core =$8250 plus freight overland 1000 miles

I guess given the labour cost (either my own labour, or paying $200/hr for someone else), it is a small additional cost to get it from Flying Spares.

I do not have any reason to think that the engine from the florida place would be bad, other than when I was at that particular used RR dealership 15 years ago, the salesman was pressuring us to buy one of two junky Corniche that they could not even get to start by jumpstarting them. They actually chased us out of the lot asking if we would buy today. And the photo on ebay shows their rebuilt engine a little bit crudely spray painted, and they did not use the right colours, they sprayed the silver on the heads and the block. (plus I don't want my block painted at all, I only want heads painted (black, not silver). And in their advertisement for the rebuilt engine, they used the same ad copy that Flying Spares uses for their rebuilt engine.

I would hate to install it, only to have a weep hole leak or who knows what go wrong, even if it does have a warranty. Especially if I decide to have a man do the install which will be at least $6k in labour.

Does anyone have any alternate ideas? I did see a website for a place in Las Vegas that says they can rebuild the existing engine for near enough to $10k. (on the east coast, it is more around $30,000 at a place like Robison or Palma)

I like the idea of a rebuilt engine, that way I don't have to wonder when the liner seals will quit, or what caused the low pressure and then the metal shavings in the first place. I hope the only reason for the low pressure was the oil filter was assembled without enough pieces, so that essentially, no oil was being filtered, for at least ten k miles. This allowed metal to wear the bearings away which lowered the pressure which made more wear etc. But that is only a guess. Maybe the reason the pressure got low was someone overheated once it long long ago, and block stretched and over clearanced the bearings.

It has always run cool and perfectly in my ten years, and I have used it in all conditions.

My concern with a rebuilt engine, is how badly was the donor block corroded from 50 years of not frequent coolant changes? How much RTV did they have to add to the liner seals to make them seal? And how long will that last? (I think if I did my own rebuild, I would have a machine shop clean up those liner seal bores in the block and then I could use a slightly thicker o ring there...I don't like the idea of putting RTV around the o rings to fill in corrosion spots. That is fine for a Cloud ii that will not see another thousand miles in the next hundred years, but my car works for a living, is my only transport, is used to cross a country without public transport, and I intend to put at least another 100k on it in next 5 years.).

I think I could trust that Flying Spares would use a good uncorroded core (if such a thing exists), because they really have their choice of hundreds of them. The place in Florida only has about 20 cars in their junk yard last time I checked.

Also, is there any point in ordering the long stroke motor for the replacement? (My car has the 6.2 Litre short stroke motor, with high compression, which I love).

The whole thing is rather disheartening. I sometimes think of just getting a different shadow or even a 20k spur to use, and just put this car in a storage unit until I have time to fix it. (the reason I don't want to do that is because then, the replacement car will become a thing that takes money away from the car we love which we want fixed, and which we intend to do bare metal respray next year)

Sorry for such long writing. I really appreciate the wisdom of folks here.

I guess the best news would be if someone knew of a shop on the east coast that could rebuild my engine for about $10k and I would not have to get another engine at all. The eastern US guys are at about $30k for a motor rebuild. Maybe most of that is labour for the removal and the install. Maybe I should call these good Eastern guys, such as Palma, and Robison, and ask what it would cost to rebuild if I deliver and pick up the engine on a truck? And do not ask them to install any brake pumps or accessories.

Cheers.
 
#3 ·
I know Robison and have visited his shop a few times and talked about our days in the rock n roll business. He is very smart and has a great business with long time employees. You get what you pay for and it will be expensive but you know you will have the car forever so amortize the cost of doing it the right way. Palma is very good also and I can't say which is closer.
I see you have an earier car so therefore no steering rack to get in the way. You could pull the pan and totally clean it. I suspect there is sludge that circulates and that is now being trapped by the filter like it should. By the way the spin on modification is worthwhile, I did it on my 1972 Shadow.
When the pan is down you could remove a few bearing caps to observe and more importantly measure the crank journals and look at the bearings. I would base my future decision on the bigger picture once the results are in. I would stay away from the Florida guy. I know them and have done some parts business.
If it were me, I would buy a beater car and put the RR in a safe place where you can work on it. I have pulled engines ( I prefer to drop the subframes) since I have a great Mohawk lift and a steel girder ceiling grid with trolleys. In a worse case scenario you could pull the engine and bring it to one of the shops mentioned. You will save thousands on the labor. In the end a properly rebuilt, if it goes that far, will add to the value of the car.
I wish you were closer to help you.
 
#4 ·
I'd be inclined to pull or drop the motor and rebuild it, the Rod/Mains are probably wearing quite quickly hence the metal in the oil and the low oil pressure.

Those metal bit's won't be doing the Oil pump and the top end any good.


I'd stop driving her in my opinion.

and give a full rebuild.


What grade oil are you running?
 
#5 ·
I am using 15 40 full synthetic. I only do this synthetic now, because it can handle more heat than regular oil. I figure low pressure means more heat.

Before I noticed this trouble I used 10 40 or 20 50 regular oil.

Will there be any way to tell what caused this low oil pressure in the first place? (I hope it was just because someone put in the oil filter without the right parts and the oil was not getting filtered for many many years, but it could have been something else). First thing I am doing is putting a shadow ii oil filter system in it.

I have not used the car in the last 6 months, I have been borrowing a car. I did not want to run my car until it broke. I wanted the chance to fix it without fancy machine work and inserts in the block and align boring etc.


My borrowed car is going away soon, and then I will need to put about 500 more miles on the car before I get enough money to fix it. (If I just do bearings and oil pump, that would only be to keep me going for a while until I get a my new shop, and my other cars, and essentially, get the chance to take it apart myself in my shop and pull the liners and everything else and make it perfect. I just don't see that happening for at least 18 months, and I need a car in the mean time.
 
#6 ·
Well, I just looked again at the advertisement for the Rebuilt engine from the place in Ft Lauderdale. It has 1 review, written by a customer who states:

"Beware do not buy his engine
I purchased one it was not rebuilt and arrived with a cracked block and was put together so bad it had to be done all over again . Do not waste your money"
 
#8 ·
I forewarned you about the place in FL. Think again about rebuilding what you have because in the long run it's yours and part of the car's DNA.
You could save buckets of money by pulling the old one and bringing to Palma or Robison. They will not be about to give you any quotes because so much depends on breakdown and inspection and then measuring. That's the process. If they start at the bottom end and all looks good, there is as immediate savings. If a head(s) are pulled, the valves van be ground, stems checked, updated stem seals (very cheap to do) and then a preliminary measurement and inspection of the bores. If no liners and pistons are needed you will save thousands in parts and labor.
You do not want to go thru this again with a replacement from a junkyard or a shoddy rebuild. "Do it once and do it right"
Just some advice.
 
#9 ·
Thank you wraithman and others.

Regarding the retrofit of the SSii oil filter kit, when replacing the spin on filter can, it goes on horizontally. Does that mean we are supposed to install the spin on filter without oil in it? (It would just dump out). Is this ok? Will the pump just fill the oil filter whilst cranking? Should I remove fuel pump fuse for first time cranking, to fill this filter completely with oil prior to allowing ignition?


Does anyone think the engine job could be done perhaps in the neighborhood of $8-12k if I bring the bare long block to a good place like Robison or Palma? (I don't have a labour hours chart, perhaps the labour alone is $20k).

I could even do the heads myself (with a good local machine shop). That might save some money. Maybe just bring short block to Robison. I would ask him about that. Perhaps he wants his own autopsy, starting with heads attached.

If block is not rebuildable, I suppose a good used core block could be found. Then the rebuild continued with that.

I will report progress as it comes. I am in Delaware at the moment and scheduled to move out west by the end of the year. I hoped I could have the car done before then. If not, I guess it gets trucked out there and I do the whole rebuild myself in a new shop out there.

Cheers everyone, and thank you.
 
#10 ·
I would wait and move. I would highly recommend Ronny's Garage. I have talked to Ronnie many times and he is a RROC technical adviser with Youtube vids. I highly recommend his video on the Silver Cloud motor. It is basically the same block and you will get more insight in what is involved. You can probably avoid pulling the liners and this will save buckets of cash.. I would concentrate on the lower end after the sump is removed. Ronnie will give you a very honest appraisal and work with you.
 
#11 ·
I am frightened reading the coct of a re-build in USA,I know you would like to do the original engine but take time and look at all options,look at good secondhand engines,
There is a company in UK (Westminieter auto salvage) who will sell a good engine for a fraction of the price,In Uk these cars are scrapped due to Rot and not wort re-doing as they will not pass the annual government test.Most of these cars in England have been serviced as recomemded and are perfect.
In Ireland I just purchased a complete running engine out of a 1985 Silver Spirip,the car was rotten ant the engine had 88,000 miles on it and it sounded perfect I paid 1,000€ For it,is going into a. Bentley Eight and we are having the old engine taken out and this engine hitter for 1500€ a total cost of 2500,there will be some extra cost for new mountings etc.There is an abundance of engines in UK for sale,Flyinh Spares may be the most expensive
I can get the number for you if you want it.I have bought some parts from them and I was happy with the service and prices.
 
#12 ·
Kevin, The reason the cost for a total rebuild is expensive is the following. Time: Labor rate is 125-150/hr. Components have to be measured and cleaned and once that is done the game plan is to replace worn out parts and recondition others.
When everything thing is done the rebuilt motor will have zero hours on it.
A used motor has unknown running time, unknown maintenance history and at the end of the day it is used.
If it were me and I was keeping the car I would do a textbook re-build. You could buy a used motor to keep the car on the road with the intention of re-building the original in the future and then sell it to recoup.
Like everything in life...time and money
 
#13 ·
Spiritofx,
My humble opinion, and course of action would be:
1. as suggested before, have the oil analysed, they will be able to tell you if the metal is bearing material,
2. if so, then you may attempt to change the bearings the way you suggested.
3. step 2. will, however, not correct the reason the bearings are dying. My main suspect would be the oil pump, the workshop manual (attached, albeit for a 6-3/4 engine) has a way of bench-testing the oil pump. A bit elaborate to gain access to it.
 
#15 ·
When you arrive in CA you could dial up Tony Handler a long time source of used parts and save the long distance shipping costs. He is a respected source for many years and is often quoted as a source by RROC members. The reputation of the seller is almost as important as the condition of the motor itself.
 
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