GolfGTIforum.co.uk
Model specific boards => Golf mk3 => Topic started by: Khare on 03 March 2013, 13:31
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DRY TEST
Cyl 1 - 192 PSI = 13.2 BAR
Cyl 2 - 190 PSI = 13.2 BAR
Cyl 3 - 200 PSI = 13.8 BAR
Cyl 4 - 200 PSI = 13.8 BAR
WET TEST
Cyl 1 - 196 PSI = 13.5 BAR
Cyl 2 - 205 PSI = 14.1 BAR
Cyl 3 - 210 PSI = 14.4 BAR
Cyl 4 - 210 PSI = 14.4 BAR
Done this morning as cylinder 3 (cylinder 4 being gearbox end) has an oily plug and I was down 6hp on the dyno since last month.
It's not piston rings as there's little difference between wet & dry results. Nice and high compression and consistent across the 4 cylinders. So it all points to a leaking valve stem seal. It smokes a bit on idle but it's water in the exhaust rather than oil. It burns about 300-500ml every 6000 miles or so.
So time to find a spare ABF head, port it and grind the valves in, change the seals and skim it. That way I do headgasket too, which doesn't need doing but it helps on resale later on at some point :smiley:
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Hi mate,
I think this is what your looking for (if I'm wrong my bad)
http://www.golfgtiforum.co.uk/index.php?topic=249636.0
Its not mine but thought it might be helpful for you :)
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Your losing through your valve if its not the rings, the stem seal is an oil seal and the guide is just as its name describes.
Sounds like you have a worn valve/head, which would knacker the oil seal eventually.....
Fix is the same best go as planned and get a spare head and take it from there :smiley:
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Probably the exhaust valve guides worn. Had 8 done on mine when I had the head off. £13 a guide adds up thought.
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My work needs to be done within the day, so I'll be buying another head, working on that then swap it over within the day. I think I might do exhaust manifold while it's there easily accessible.
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My work needs to be done within the day, so I'll be buying another head, working on that then swap it over within the day. I think I might do exhaust manifold while it's there easily accessible.
Get yourself a complete top end and match the lot, should see you another 5/10 and not cost much more than buying a head
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That's what I'm planning on doing, port matching the thing and aiming for 170hp.
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If you got the cash why not throw in some cams?
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That's what I'm planning on doing, port matching the thing and aiming for 170hp.
You need to be careful around the bolt clearances so that you get no overlap when fitting back together.
When you start make your self some datum edges, preferably get someone to mill some flats across the intake assembly as this is piss easy. Also its good to sleeve the head studs and ream out the holes in the manifolds to ensure accurate location, once you have done this leave the studs in as they are your datum.
In principle its best to match exactly the joins but in life this is very hard to do without getting proper workshop, if you have to step out .25mm per side to ensure flow path does not get any interruptions due to inaccurate datums then that is the best route to take.
Makes sure you pay attention to fitting the gaskets as this can ruin gains if they interrupt air flow.
You should be able to go from the flange where the TB joins the inlet to the first join then from there to the head, then head to exhaust manifold. cant remember how the ABF downpipe joins the manifold but the KR had a few mm which could be opened up and improved.
TB can be easily de humped and enlarged at a later date.
I would avoid messing with the head and a dremmel, unless you know where to remove and what shapes you need.
I have wrecked loads of CVH heads with an air grinder :grin: