Finding oil leaks
Discussion
Chaps,
Quickie.
I have a car (Mk2 Golf GTi, 1800, PB engine, 132,000 miles), and it has a mild oil leak. Well, not so mild. It uses around 1 litre every 800-1000 miles (within VW spec, but still is a pain to check and whatnot). A couple of questions.
1. I am guessing it is leaking, not burning. I am assuming that if it was burning at this rate, it would reek of burnt oil, and burn very blue. It doesn't do either, is it therefore fair to assume it is leaking?
2. What is a good way of tracing these leaks? The usual - clean the engine and look for the oil on the side of the block/head, park it over clean newspaper, any other useful tricks?
Any help most welcome ...
Oli.
Quickie.
I have a car (Mk2 Golf GTi, 1800, PB engine, 132,000 miles), and it has a mild oil leak. Well, not so mild. It uses around 1 litre every 800-1000 miles (within VW spec, but still is a pain to check and whatnot). A couple of questions.
1. I am guessing it is leaking, not burning. I am assuming that if it was burning at this rate, it would reek of burnt oil, and burn very blue. It doesn't do either, is it therefore fair to assume it is leaking?
2. What is a good way of tracing these leaks? The usual - clean the engine and look for the oil on the side of the block/head, park it over clean newspaper, any other useful tricks?
Any help most welcome ...
Oli.
If your sure it's not burning it, which tbh is still quite possible without you seeing the blue smoke at this stage. I favor the use of UV reactive dye in the oil and then search for the source of the leak with a UV lamp.
I'd have also thought a LTr of oil leaked onto the engine would be visable.
I'd have also thought a LTr of oil leaked onto the engine would be visable.
Rob,
132,000 miles. If it is possible to burn oil at this rate and not see it in the exhaust, then I guess it is a possibility. Having said that, the plugs are a healthy fawn colour, which suggests that it is not burning oil.
Nighthawk - where would I go looking for some UV-reactive dye? This sounds like a very neat solution. Would the presence of the dye potentially cause problems in the engine?
Oli.
Edited to add the bit about the plugs.
>> Edited by zcacogp on Wednesday 11th August 17:34
132,000 miles. If it is possible to burn oil at this rate and not see it in the exhaust, then I guess it is a possibility. Having said that, the plugs are a healthy fawn colour, which suggests that it is not burning oil.
Nighthawk - where would I go looking for some UV-reactive dye? This sounds like a very neat solution. Would the presence of the dye potentially cause problems in the engine?
Oli.
Edited to add the bit about the plugs.
>> Edited by zcacogp on Wednesday 11th August 17:34
your spark plugs aren't going to show anything on such a small amount of oil ingress into the combustion chambers.
if we work on the assumption that your losing a litre per thousand miles, that just 1ml per mile! thats an awfull lot of combustion cycles in which to lose a ml of oil.
for something like that, it could very easily be a valve stem oil seal allowing oil to run down the valve. from there it would be quickly burnt off by the time the engines warmed up,leaving the nice biscuit brown colouring on the plug ceramic.
however, a litre of oil leaking onto to the outside of the engine block will be noticable.
I got my oil leak kit from snap on, but i'm sure other tool companies do similar products.
the dye is perfectly safe for all systems. i often use it in transmissions,engines,diffs and A/C systems.
if we work on the assumption that your losing a litre per thousand miles, that just 1ml per mile! thats an awfull lot of combustion cycles in which to lose a ml of oil.
for something like that, it could very easily be a valve stem oil seal allowing oil to run down the valve. from there it would be quickly burnt off by the time the engines warmed up,leaving the nice biscuit brown colouring on the plug ceramic.
however, a litre of oil leaking onto to the outside of the engine block will be noticable.
I got my oil leak kit from snap on, but i'm sure other tool companies do similar products.
the dye is perfectly safe for all systems. i often use it in transmissions,engines,diffs and A/C systems.
Nighthawk,
Hmmm, hadn't thought of it at 1ml/mile. Makes it look like not very much, doesn't it ...
Didn't know that SnapOn did things like oil leak trace kits. I thought it was just a good idea of yours! How much was it/where can I get it from. Actually, I'll just take a trip to my local motor factors and see what they can get for me. Thanks for the help.
Docevi1, It does have a small drip on the bottom of the engine ... which is what makes me think it is leaking, not burning. And other people tell me that the sump seal is often a weak spot. And this would explain why there isn't a large streak of oil down the side of the engine ... I think this has to be the first line of attack, eh?
(Of course, I have to hold in mind the fact that this car cost £500 a year ago, so it isn't going to be worth spending much on fixing the leak/burn. And putting in a quid or so of oil every now and again isn't going to mount up too much for the rest of it's life on the road.)
Thanks again for your help chaps.
Oli.
>> Edited by zcacogp on Thursday 12th August 17:25
Hmmm, hadn't thought of it at 1ml/mile. Makes it look like not very much, doesn't it ...
Didn't know that SnapOn did things like oil leak trace kits. I thought it was just a good idea of yours! How much was it/where can I get it from. Actually, I'll just take a trip to my local motor factors and see what they can get for me. Thanks for the help.
Docevi1, It does have a small drip on the bottom of the engine ... which is what makes me think it is leaking, not burning. And other people tell me that the sump seal is often a weak spot. And this would explain why there isn't a large streak of oil down the side of the engine ... I think this has to be the first line of attack, eh?
(Of course, I have to hold in mind the fact that this car cost £500 a year ago, so it isn't going to be worth spending much on fixing the leak/burn. And putting in a quid or so of oil every now and again isn't going to mount up too much for the rest of it's life on the road.)
Thanks again for your help chaps.
Oli.
>> Edited by zcacogp on Thursday 12th August 17:25
depending on how far you wanted to go into this....purely for the sake of tinkering 
have a cylinder leakage test carried out to establish exactly whats going on inside.
I don't hold with your theory of not spending money on it, after all, if it drips a single drop of oil in the same place every day you'll soon have a patch of oil on the road which could quite possibly endanger the life of a biker.
i know i've taken that to distant and unrealistic extremes, but oil leaks erk me somewhat.
Snap on do diagnostic tools far an above what most dealers ever use, so tools for the sunday morning technician are a formality
anyhow, hope you get it sorted
have a cylinder leakage test carried out to establish exactly whats going on inside.
I don't hold with your theory of not spending money on it, after all, if it drips a single drop of oil in the same place every day you'll soon have a patch of oil on the road which could quite possibly endanger the life of a biker.
i know i've taken that to distant and unrealistic extremes, but oil leaks erk me somewhat.
Snap on do diagnostic tools far an above what most dealers ever use, so tools for the sunday morning technician are a formality
anyhow, hope you get it sorted
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