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blue_2cv
2CV Fan
Joined: February 26th, 2013, 6:35 pm Posts: 44 Location: East Sussex, England
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 Excessive oil consumption
Hello everyone. I thought I'd do a bit more maintenance to my car and would like a bit of advice! Basically at the moment it has a rather extreme addiction to oil to the extent of polishing off pretty much its entire capacity in about 500 miles. Although it's not quite as bad as it was, its not ideal. Looking at the engine there is no visible oil leak but then saying that there's not a huge cloud of smoke left behind it either. I've looked in the Haynes and by power of deduction it can't be worn piston rings and cylinders as they're new (I did also make sure that the gaps in the rings were evenly rotated when I fitted them). I can't see any visible oil leak since changing the rocker cover, so it must be the valve guides. Looking on Ecas there seem to be standard and over sized valve guides. Pardon the obvious question but if there's no movement around the valve guides, can you get away with replacing them with standard? If you use oversize guides, do you have to drill the head out at all in order to fit? One other thing is that the engine seems to make a tapping noise so whether that relates the valve guides or possibly worn valve gear, I'm not sure. I think Spanners left that engine outside with the rocker covers off for the best part of 15 years so it can't of done it much good! We did lap the valves and cleaned the up heads in general and I'm pretty sure we replaced the valve stem seals. I should also point out that despite what you have read, the car starts and drives perfectly. 
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March 23rd, 2015, 1:16 am |
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banjo
Firing on two.
Joined: June 5th, 2009, 9:17 am Posts: 747 Location: Staffs & France
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 Re: Excessive oil consumption
You haven't perforated your rocker covers by over tightening the centre nut,causing he rocker to hit it? Or worse the push rod tubes have been distorted when the heads were fitted? If you were burning that much oil you'd seen the smoke screen behind you 
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March 23rd, 2015, 8:38 pm |
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lpgo
Firing on 1-2 Spark
Joined: November 8th, 2009, 5:42 pm Posts: 2847 Location: NL
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 Re: Excessive oil consumption
_________________
Russell wrote: Hi Geo, you've been one of the sites biggest attractions in recent years. Russ
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March 23rd, 2015, 8:45 pm |
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Sean
Firing on two.
Joined: April 22nd, 2009, 11:06 pm Posts: 3684 Location: Ecosse
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 Re: Excessive oil consumption
ow this mornings reply didnt upload
The oil has to be going somewhere its either leaking out - usually obvious, or being being burnt
If new rings are fitted to old worn barrels they will snap, new rings not run in properly or fitted the wrong way up will lead to horrendous oil consumption. dont worry about the rings gaps they dont stay where you put them for long.
Smoky exhaust on the over run or when you stomp on the pedal after coasting for a bit is often the valve stem seals. Id not worry to much about over size stuff they go on for ages, the seals can easily get damaged on insertion. Fitting a gide isnt really a diy option as it should involve work to the valve seat when done properly
best to run some diagnostics comp. test and/or leak down test will give you a good idea of where the problem is likely to be.
over advanced timing can increase oil consumption
_________________ Kissing the Lash
 "Any advice of a technical nature is given on the understanding that I've actually done this shit, not just read about it in D*lly club mag some time ago.
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March 23rd, 2015, 9:58 pm |
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blue_2cv
2CV Fan
Joined: February 26th, 2013, 6:35 pm Posts: 44 Location: East Sussex, England
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 Re: Excessive oil consumption
That was once, and it wasn't my fault, honest! I used a torque wrench  I think it had been over tightened in the past. But I have since changed it and it definitely doesn't leak anymore. I don't think the push rod tubes were distorted when fitted, I certainly didn't force them on there. I'm fairly convinced it doesn't leak around the push rod seals as I would have thought it would have made its way down the outside of the sump. The oil MPG was only a estimate I couldn't tell for sure but there defiantly isn't a smoke screen. In fact you wouldn't know there was a problem to drive it. Maybe somebody's siphoning it! banjo wrote: You haven't perforated your rocker covers by over tightening the centre nut,causing he rocker to hit it? Or worse the push rod tubes have been distorted when the heads were fitted? If you were burning that much oil you'd seen the smoke screen behind you 
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March 24th, 2015, 12:00 am |
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blue_2cv
2CV Fan
Joined: February 26th, 2013, 6:35 pm Posts: 44 Location: East Sussex, England
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 Re: Excessive oil consumption
I'll certainly give that a go!
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March 24th, 2015, 12:09 am |
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AZL57
Firing on two.
Joined: October 22nd, 2014, 10:59 pm Posts: 2225 Location: South-Limburg
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 Re: Excessive oil consumption
is your breather valve ok?
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March 24th, 2015, 9:13 pm |
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blue_2cv
2CV Fan
Joined: February 26th, 2013, 6:35 pm Posts: 44 Location: East Sussex, England
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 Re: Excessive oil consumption
I think so. The breather came off my other accident damaged car and I never had any trouble with the engine in that car. I don't really know what to look out for in the breather!  There isn't any oil in the air filter and the engine has a good vacuum at idle/low revs so I assume its fine?! I should also point out that it isn't physically damaged in any way. AZL57 wrote: is your breather valve ok?
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March 25th, 2015, 1:06 pm |
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bobh
Firing on two.
Joined: March 26th, 2010, 8:41 pm Posts: 234
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 Re: Excessive oil consumption
See posting Backfire. Before my engine "collapsed" it was drinking oil, so I fitted an ECAS breather valve. Unfortunately it went pear shaped after that, but I don't think the breather valve was anything to do with it. On stripping the engine down, the top ring groove was 1.0mm wider than the ring thickness. BobH
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March 25th, 2015, 7:38 pm |
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AZL57
Firing on two.
Joined: October 22nd, 2014, 10:59 pm Posts: 2225 Location: South-Limburg
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 Re: Excessive oil consumption
Yes wider ring grooves have a oil pumping action...
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March 26th, 2015, 12:13 am |
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