I drive an old 90k mile '88 VW Jetta 16v. I have had the car two years. Occasionaly there is visable blue smoke from the exhaust as the engine is started. I put this down to oil leaking into the metering head via the breather pipe. I am starting to be concerned about the general condition of the engine, in particular the valve guides and stems, and the valve stem oil seals. At a recent MOT the car recorded a HC count of 65 ppm- is this figure useful in determining how much oil is being burnt? Additionaly, despite changing the tappets and cam chain, a couple of the tappets at the cam-belt end have become a bit noisy, yet the car recently produced 124bhp at the wheels, with the only modifications being a high-lift inlet cam, and a vernier pulley. I wondered if there were any knowledgeable people out there that could tell me how best to assertain the conditon of the engine, and how soon a head rebuild will be likely?
Thank you for any response,
Ben Chapman.
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Ben,
You have a well regarded engine here with a huge spares supply network outside the dealer system.
If all you have is a couple of lazy tappets and a small puff of oil on startup then this is quite in keeping with the age/mileage.
Both these faults are likely to be resolved by a head overhaul if they annoy. If you car pulls well otherwise without any nasty tapping/knocking then I would just keep up regular quality oil/filter changes and enjoy it.
David
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I am a bit annoyed with the tappets, as they were replaced about 8k miles. I wondered whether anyone knows if tappet bore wear is a problem on this engine, or is it more likely that i have faulty lifters? I was hoping it was faulty tappets since the rest of them are ok. That will teach me not to use pattern parts- i just couldnt afford the £493 pounds my VAG dealer was asking for a set!!
Ben
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I'm sure my VW loving brother wil have something to say here but.....
I wouldn't be too alarmed with this noise & smoke
If it really annoys you, why not go for a 2.1 16V conversion? That way you would get a reconditioned engine together with a large performance hike
I don't think that it would be wise to just recondition the cylinder head, just think of the possible wear on the bottom end
I have seen many 16V VW engines pushing out a fair bit of smoke - if it just happens at start-up then don't worry.
Rgds
David
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If i wanted a capacity increase I would go for a Corrado 9A block- 2.1 ltrs dont rev to well, plus the pistons are expensive. However, a decent proted head will release more power.
Could you ask your brother if he knows how to stop this oil getting into the metering head?
Ben
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OK - here we go!
I had a 1987 MKII 16V and clocked up 170,000 miles with it without any engine problems even though at the end it smoked on start up only, like yours, and the tappets were noisy until warm. I did nothing about it and in went better the older it got. If the noise bothers you - fit a decent stereo!
Regarding the oil in the metering head - I had this problem identified by my K&N being sodden in oil and traced it back to the breather pipe from the engine block close to the oil cooler. It is fitted to an assembly a bit like an anti-splash guard and that can sometime collapse. The other thing to check is that the pipe from this breather to the air box isn't soft as this will effectively "suck" up oil.
Ever thought about an LPG conversion? Your engine will run smoother!
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Thanks for the reply. It only smokes occasionally on start-up, and im quite sure its oil getting into the metering head. You are right about the gauze in the breather pipe. Pattern parts do not have this gauze at all. I will have to buy a new VAG one, as mine has gone soggy, and see if this sorts out the problem. Although i have an additional oil cooler, i think the Mobil 1 0w-40 i put in the car for the winter is a bit too thin for this engine. I will be using Valvolene 5W-50 full synthetic all year round from now on, i think this is the best oil you can buy for this engine.
Re the tappets. Mine make no noise from cold (well none thats audible with the bonnet down). It's only when the engine reaches operating temperature that two of the tappets tick with the bonnet up- im starting to think they could be faulty. I might replace them with a few Kent Cams tappets.
Do you think its worth having the oil pressure tested? The oil pressure at idle on a good standard car is quite poor- i think it could be a good idea to replace the pump with a 2ltr 16v item.
Ben
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A question for you professionals-Is the HC content figure as checked in the MOT emission test- a check on the content of Oil etc within the exhaust gas?
My Astra produced a test result of Zero ppm vol last year, at todays MOT test the reading was 12ppm- well within the pass range of less than 200, but should imterpret this as a sign of engine wear-The Car has now covered 84,000 miles??
Thanks for replies
Andrew
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An autoengineer told me that the particles produced by burnt oil are too big to register on the HC test.
Phil
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HC's are due to unburned *fuel* and has b*gger all to do with oil unless you are burning litres of it.
Don't try any fancy oils in your mota - stick with recommended semi-synthetic 10W40. Full synth can loosen the engine up and remove deposits leading to an oil burner - this could be your failing. A 13 year old VW engine does not warrant Mobil 1 or anything similar.
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What Guy says is right about Mobil 1 in these VAG 16v engines. I had one a few years ago and the first fill of Mobil 1 (5w/40 in those days) turned dark brown with flushed off deposits within a week. I changed it after 1,000 miles. The fresh oil continued to removed accumulated tars, gums and carbon. After that, the oil stayed relatively clean, didn't leak and gave the car a very smooth start up. But fully synth in an 8v GTi caused all sorts of gasket leaks. I wonder if Ben's problem is the short chain connecting the two camshafts. That could be due for renewal. He should have bought my 16v Jetta. He saw it. Drove it. Reckoned it went much better than the one he bought. But was worried about noisy gearbox bearings.
HJ
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Surely it is a good idea to remove the dirt that can build up in engines? When i bought mine i removed the sump in case there was any accumulated "junk". Junk tends to build up in the sumps of this engine, as a fair amount of oil remains in the sump when the oil is drianed. I concluded that if any significant wear had taken place to the cams, followers etc, that the remains would accumulate here, and wreck my main bearings. Thankfully there was no junk.
I believe Mobil acknowledged that its oil could lead to premature failure 8 years ago, and subsequently changed the formula. How long ago did you experience problems?
Soon after i bought the car, i removed the rocker cover to investigate the condition of the cam chain, as HJ had mentioned these could wear. The chain appeared tight, but i replaced it anyway, along with a set of tappets. At the time i fitted a high-lift inlet camshaft. The tappets, 15k miles latter still make no noise when starting from cold. However, two at the cam-belt end occasionaly tick when hot, which makes me think they are faulty. If i get time i will replace them and see if that cures it. Earlier 16v engines are noisier than later ones due to the different shape of the teeth on the cam-chain sprocket. When i changed the inlet cam, i stuck in a 40k mile cam from a J reg 16v, this had the more rounded teeth.
One reason HJ's Jetta went better than mine when i bought it (thats if anyone is interested?) was because it was fitted with a 42mm inlet manifold. VW fitted 50mm intakes to 88' Model year cars onwards. These manifolds loose you 7 ft/lb of torque at peak. VW stuck to the 42mm for the mk.3 and Corrado. As a result i have stuck a 42mm manifold on my car. The manifold, intake cam, and a vernier pulley have increased mid-range torque from 119 ft/lb (which is standard for a 50mm car) to around 135ft/lb of torque (107bhp @wheels at 5k rpm). As a result the engine has a far better power curve, and i have lost no top-end power. Other than the pulley, i have profitted from changing the manifold and the cam. Cheap power. I think when the valve guides wear out, i will get the head ported by the wonderful David Baker if i can afford it. Then it might make some decent power.
I have cleaned the oil out of the metering head, and placed additional gauze in the breather pipe. I have seen no oil from the exhaust since then. I have thrashed the car for the past 1k miles and it appears to have used about 1/6 of a litre of Mobil 1, though i think a tiny amount may be leaking from one of the pipes to my Mocal oil cooler- is this excessive oil consumption from this engine?
Hj, the gearbox bearings didnt put me off your car- i could hardly hear them- it was the body work, lack of power steering, and the price you were asking for it at the time. I can do mechanical work reasonably, but i am useless with bodywork. The car i bought still has no rust other than a small amount around the scuttle gromit. When i bought it, it had recently had a new exhaust, alternator, raditor fan, two new tyres, a full service, and new engine mount. The car also had power steering and 256mm brakes. The interior was virtually brand new appart from the drivers seat.
The other cam type noise has turned out to be faulty water pump bearings. I had the water pump replaced about 2k miles ago, so i am not pleased. It makes the car sound like the small end-bearings are about to give up!!
"Don't try any fancy oils in your mota - stick with recommended semi-synthetic 10W40. Full synth can loosen the engine up and remove deposits leading to an oil burner - this could be your failing. A 13 year old VW engine does not warrant Mobil 1 or anything similar."
I cannot see any reason why synthetic oils are not reccomended for 13 year old VW enigines? I use Mobil 1 in the winter, and Valvolene 5W-50 in the summer. Synthetic oils last far longer than mineral oils, and protect the engine better. I know which i would rather have supporting my bearings at 7k rpm. The Mobil 1 will lubricate far better from cold, and when hot than a 10w-40 mineral base oil.
Ben
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