VW Aircooled Sooty Inlets
Howlor - 10/1/09 at 01:06 PM
Hi All,
Just thawing out after removing the camper engine. I've searched the usual VW forums but they are never as good as this!
The inlet manifolds are sooted up about 3-4"s in. Is this that the exhaust valves may be kaput or do we think it could be normal?
All ideas welcome.
Ta,
Steve
britishtrident - 10/1/09 at 01:20 PM
Sounds like valve clearances to close most likely root cause either due to maladjustment or valve seat recession.
You could do a cylinder leak down test but it isn't worth the effort when the engine is already out --- do a decoke and lapp in all 8 valves.
rusty nuts - 10/1/09 at 01:37 PM
quote:
Originally posted by britishtrident
Sounds like valve clearances to close most likely root cause either due to maladjustment or valve seat recession.
You could do a cylinder leak down test but it isn't worth the effort when the engine is already out --- do a decoke and lapp in all 8 valves.
Depending on which engine you have it may be a waste of time when exchange heads are easily available and are fitted with new valves and guides. VW
air cooled engines are very prone to dropping exhaust valves,especially on number 3 cylinder and also suffer badly with cracked heads. If you strip
the heads off its worth removing the barrels cleaning the pistons and fitting new rings. Don't forget to lap the barrels into the cylinder heads
using a bit of fine grinding paste before fitting the barrels as there is no head gasket fitted. If the engine is a 1600 with adjustable tappets set
the tappets to 0.008" rather than the 0.006"given in manuals . Also when the inlet manifold is off it may pay to clean out the preheat pipes
that run through it from side to side as they get blocked causing poor running in cold conditions . Fuel consumption will improve as well.
Howlor - 10/1/09 at 02:17 PM
Thanks guys, great help. Keep me busy for a few nights then.
Steve