Now what?

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jasper5
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Re: Now what?

Post by jasper5 »

Talking about facts, when you take your car for MOT, the computer software will not allow the test to proceed without the temperature of the oil being correct. The tester has to insert a probe into your sump via the dipstick hole to test for oil temperature, you should have known that if you were an expert.

What about cars that don't have cats/particulate filters as standard?

The difference in emission figures is between turbo and non-turbo, not cat and non-cat like petrol engines are.
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DaiRees
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Re: Now what?

Post by DaiRees »

jasper5 wrote:Talking about facts, when you take your car for MOT, the computer software will not allow the test to proceed without the temperature of the oil being correct. The tester has to insert a probe into your sump via the dipstick hole to test for oil temperature, you should have known that if you were an expert.
Is that just for diseasels? 'Cos I had my MOT last Monday and he definately didn't do that.
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jasper5
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Re: Now what?

Post by jasper5 »

Not only diesels, petrol as well, but on a petrol engine,with a cat test, the tester can select warm engine from his computer screen.

If the car passes the test from the initial run through of the test program then the temperature need not be taken, if however, the car fails the first test, the tester has to do a "further conditioning test"....this means taking the temperature of the oil as I described earlier.The test is now run for 180 seconds with a fast idle test and an idle test at the end, sometimes this produces a pass figure even if it failed first time round, some cars need this longer test to "light up" the cat.

Longintooth was correct in saying take your car in when it is hot however, usually saves the need for the longer test.

The test will not proceed on a diesel engine until the temperature of the oil is within test limits.
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Re: Now what?

Post by Longintooth »

jasper5 wrote:Talking about facts, when you take your car for MOT, the computer software will not allow the test to proceed without the temperature of the oil being correct.
Gee man - the oil temperature is not a reliable source for indicating the CAT temperature - the exhaust gas temperature is higher than you can imagine. On diesels the Tester is advised to floor the throttle for a short time to get the heat into the CAT but I can assure you that this is not done enough and it is on no load - big difference to full load. Incidentally - flooring the throttle light load on a diesel is the worst thing you can possibly do to one so the quicker you get the readings the better for your motor. You see I can give you a detailed answer to any thing you say. I call some of these testers "Dipsticks"
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Re: Now what?

Post by Longintooth »

jasper5 wrote:Not only diesels, petrol as well, but on a petrol engine,with a cat test, the tester can select warm engine from his computer screen.

If the car passes the test from the initial run through of the test program then the temperature need not be taken, if however, the car fails the first test, the tester has to do a "further conditioning test"....this means taking the temperature of the oil as I described earlier.The test is now run for 180 seconds with a fast idle test and an idle test at the end, sometimes this produces a pass figure even if it failed first time round, some cars need this longer test to "light up" the cat.

Longintooth was correct in saying take your car in when it is hot however, usually saves the need for the longer test.

The test will not proceed on a diesel engine until the temperature of the oil is within test limits.
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jasper5
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Re: Now what?

Post by jasper5 »

The computer software will not allow the test to proceed if the oil temperature is incorrect, there is a set programme, you cannot alter it.

I always wait for my mot tests I take about 5 each week, I have seen the test hundreds of times.
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Re: Now what?

Post by steve_earwig »

I'm not sure if they do it in the UK but the bit I don't like is when the tester dunks something in the brake fluid reservior to test the fluid, I dread to think where else it's been!
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jasper5
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Re: Now what?

Post by jasper5 »

steve_earwig wrote:I'm not sure if they do it in the UK but the bit I don't like is when the tester dunks something in the brake fluid reservior to test the fluid, I dread to think where else it's been!
They don't do that here, they should, they are testing for water in the fluid, if there is water in the fluid and if you heat your brakes up to a certain temperature, the water will boil and produce air in the system causing loss of braking.

That is the reason why the brake fluid should be changed every 2 years or so.
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Re: Now what?

Post by steve_earwig »

Sorry, I know what it's for (I asked :cheesy: ) and it is a good idea, you just haven't seen the garbage on the roads here, I could end up with swarf or even pig's urine in my brake fluid :shock:
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Longintooth
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Re: Now what?

Post by Longintooth »

jasper5 wrote:The computer software will not allow the test to proceed if the oil temperature is incorrect, there is a set programme, you cannot alter it.
Yes I know that sir - that's why I'm advising a way to make sure you get a quick sure fire result because the geeks that wrote the program miss little facts out that we on the ground know about such as some deterioration due to age. Remember to give it some welly before you take it in - it will look much better than a just pass. Oh and whilst were on the subject (Not for you Mr Jasper) the gasoline emissions testers are so sensitive that just the slightest puff of a leak in the exhaust can make it difficult to pass the test. Some exhaust manufacturers put little pin holes in silencers to drain water but even these can cause problems.
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Re: Now what?

Post by steve_earwig »

Bugger. I need a new cat :( The guy took one look at it and said there's nothing they could do - any kind of bodge wouldn't last long. He said as I did about the welding, it'd just blast holes in it, and these sleeves won't help because the pipe comes out the front of the cat and immediatly turns 45 degrees. It'll only be a pattern part (well, not even pattern, more generic) and won't set me back much more than a ton. The workshop's very busy just now but it goes in tomorrow morning 'cos it's me. I'm a little disheartened but I really don't think these guys would be fos as they're mates, I've spent most of the morning in the shop there drinking coffee, telling jokes and sodding about on the 'net. I did ask about decatinating it and they said they tried that - hard to start, ran like a pig and drank diesel. :?
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steve_earwig
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Re: Now what?

Post by steve_earwig »

That's the problem - dot 4 is hygroscopic
dictionary.com wrote:absorbing or attracting moisture from the air.
As Jasper says, the older it is the more moisture it will have absorbed from the air, under heavy braking the fluid can heat up and the water can vapourise causing air (well, steam) locks, nasty.
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steve_earwig
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Re: Now what?

Post by steve_earwig »

Weill, it's done. It took about an hour, they cut the old one off with an angle grinder, pieced the new one out with a lump they cut off another exhaust and welded the whole lot up with a mig:

The offending article, I don't think it could have been welded as the metal was corroded into the cat:
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Krešo (the head mechanic) offering the parts up:
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Note careful use of protective gear. He went on to burn himself on the weld.

The finished article:
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It looks a bit Mickey Mouse to me but it's made in America (where cats have been around for a little bit longer) and the whole lot cost me 1,000Kn (that's an economically mismanaged 130 quid). I'd have preferred to spend the money on that sump guard but “he must needs go that the Devil drives” an' all that.

Next up: apparently the center box (that massive long expensive-looking one) doesn't have much in the way of baffles left in it. "Is it leaking?" "Well, no, but.." "sorry, f@ck not given." :cheesy:
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Welly
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Re: Now what?

Post by Welly »

:arrowu: Smallest CAT of eVar :shock: :?
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Re: Now what?

Post by steve_earwig »

Comedy cat :cheesy:

It's worse than you think, there seems to be a double skin on it which is open front and back, so it's even smaller. It starts and runs ok though, dunno about the economy yet 'cos I'm still on the same tank I had before the cam belt which was bluddy months back :shock:
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