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A little low Mileage VR problem to be aware of...


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When I bought my VR a couple of years ago I was over the moon as it only had 50k on the clock but this has prooved to be a real problem.

Alot of you are aware I have had a smoking on the overrun issue develop over the last few months and initially it showed all the signs of valve stem oil seals and guides being worn.

I guessed it was worth getting it sorted and just before xmas I had the head recon'd fully at a cost of 700 notes (note that guides and seals were quite worn).

Whilst the head was off I had a compression test done, this was achieved by putting all 6 cylinders in a central position, putting an even amount of diesel in each bore and leaving it, theoretically, if all six levels drop evenly there is little to no ware on the rings and after having this done they seemed in good gondition.

I was advised that as the head was off, it was a fairly easy job to drop off the sump and replace the rings just incase. But as my business was paying for the work I didn't really want to over spend and it didn't look as if it needed doing.

Anyway, the car was put back together and ran beautifully for about three days and started to smoke again and got much worse!!

I initally blamed the garage for poor workmanship but have found out differently. Apparently alot of low mileage cars, including VRs suffer from gummed oil rings as low usage attributes to oil cack building up on and around them and ware badly and in some cases unevenly. This began to manifest itself visually as a bit of overrun smoke, as on vacuum on the overrun it was sucking oil up past the rings and burning off on throttle. After the diesel compression test was done it subsiquently washed the rings and the bores and thus the problem worsened, to the extent of smoking like it had blown up!

The VR is in the garage with sump and head off and new oil and compression rings are being fitted this week. I am praying that the rings haven't worn the bores unevenly as if they have the engine will have to come out and I will need a rebore so the new rings seal correctly.

So the lesson I have learned is that if you are going to buy a low milage car, try and check how it has been driven. Short runs will surely screw and engine, especially over several years!

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True... Regular oil and filter changes are an absolute neccessity for any 'short run' car. I think the manufacturers have allot to answer for, there's no advice given in the manuals and with these new 'super oils' being engineered to give longer service life, some engines do not see an oil change for two years :o

One of my colleagues has an Audi A6 and regularly talks about the merits of 'modern car' ownership and how his car does not need an oil change for 24 months. Showed him his dipstick after 19 months of driving, black and thin. Showed him mine, light brown and consistant.

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That has got me thinking. Now got a Land Rover Freelander for everyday use.

I bought my VR 4 years ago with 44,000 miles.

It now has 64,000 miles. So does about 5,000 miles a year. This will now be less, as it will now be used as a second car.

When I take it to work, it is about a mile up the road, so it is a 2 mile round trip. I have not used the car for over a week now, so the mileage is staying low but short trips when I do use it.

As I'm using it as a second car, better start taking it on a few longer runs or change the oil and filter more regularly! B)

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It's funny really, you will notice that all the higher mileage VRs run sweet as a nut with no problems as the majority have been motorway cars or used regularly.

I'm not saying all low mileage ones wil have problems but it's something to think about.

I once knew a guy who had an Shelby Cobra replica with a V12 Jag engine and he only ever used it in the summer, he came to use it one year and the rings had rusted to the bore, completely screwing the engine! He hadn't winterised it correctly or ran it up every now and then even though it was garaged.

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Short runs = fast exhaust rot too (unless you have a stainless)

I would say amke the journey a longer one so that the engine gets at least a few minutes at normal/full water and oil temp and change the oil and filter 2, even 3 times per year regardless. I have done this over the 2 years that I have owned my VR and can honestly say that it makes a difference and keeps the economy healthy too. I make a point of cleaning my air filter twice yearly (K&N panel) and this makes a difference also.

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As I'm using it as a second car' date=' better start taking it on a few longer runs or change the oil and filter more regularly! B)

[/quote']

Just a bit of info on that, unfortunately taking it on a longer run will not counteract the damage caused by short runs.

I'll explain how short run cars get more wear;

Let say each mile from a cold start does in itself "15" wear and lasts the first 2 miles. Each mile you do once while warmed up does "2" wear and each motorway mile does "1" wear.

The short run car has 10 starts in a week, covers 2 miles in each of those short trips and does 30 wear (2x15) per trip x 10 = 300. That's 300 wear / 20 miles = 15 wear per mile.

The normal car has 10 starts in a week, covers 5 miles as it's trips are a little longer and does 36 wear per trip (2x15)+(3x2) x 10 = 360. That's 360 wear / 50 miles = 7.2 wear per mile.

The motorway car still has 10 starts in a week, but covers 40 miles on each trip and does 68 wear per trip (2x15)+(38x1) x 10 = 680. That's 680 wear / 400 miles = 1.7 wear per mile!

At 50,000 miles, the short car has 750,000 wear, the normal car has 360,000 wear and the motorway car has 85,000 wear and is just bedding in nicely.

How it's been used makes a huge difference.

The cold start cycle on a car does most of the wear to an engine, this is because of various factors including:

1. Richer mixture thins the oil coating the sides of the bores causing "bore wash".

2. The cold tolerences are not tight allowing fuel mixture and combustion gasses to blow past the rings and into the sump, where they set about making the oil acidic. This ruins the oil much more quickly.

3. The actual starting has the surfaces starved of oil until it starts pumping round. Better, fresher oil clings to the surfaces and never actually completely drains off, thinner ruined or old oil runs off the surface leaving it exposed to initial metal/metal contact.

The products such as Slick50 are designed to coat the surface and reduce damage caused in part 3, whether you believe their effectiveness is up to you. I believe there is some merit in them, but it's not as much help as it was years ago as oils, engines and fuel injection helps control this better than back in the old carb days. GTX magnatec, is not actually magnetic, but it IS a very clingy oil and keeps a larger amount clinging to that surface - it's propertites are not disputed.

Synthetic oils cling well and also reach the surfaces quicker due to being thinner when cold, they also don't sludge or burn although I understand usage is quite high on the VR6 due to it not being designed for such thin oil. It's still better, but it will drain your pocket a little more.

If you're using it for short runs, a good quality synthetic WILL help reduce your wear.

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