hi there to cut a long storey short, 2 weeks ago and half way through a 15 minute journey home it sounded like id dropped a piston nursed it back and let it cool down for half hour started up and billowing white smoke, first thought head gasket striped the head off this morning and the top of piston 4 for was covered in mayo gasket shows a breach but not a break what I saw though is clean piston head, inlet valves and looking at the exhaust manifold shows a difference in burn and plug is also different to the others any idea what im looking at here? is this just caused by the gasket and short journey home and or mayo sat there for two weeks btw the rusty look is redex additive any advise welcomed
It's basically been steam cleaned by the cooant. I'd built it back up (check head for flatness with straight edge and feeler guages). I use fine wet and dry on a flat plate sometimes to dress the head if it doesn't need skimming, Honda recommended this a while back for alloy heads and it works a treat.
Can't answer that but its not a lot (3-4 thou ?),dependant on mileage and if the engine has been overheated ? I would suggest you get a "clean up cut "done as not worth all the work to find it leaks later,my machinist usually completes this for not a lot of money and I do it with every h/gasket job. I have found VW heads to be very solid and not prone to twist,but sure there must be others that have had examples of that happening ?. You appear to need a good cleaning of the coolant passages,both the head and the block,you don't want all that crap in your cooling system and you will notice lower running temps due to improved flow. I did a Audi 3A conversion on a 89 8V Golf and found the block had a few pits in the cast iron ,I used an oil stone to correct and then used dry sand paper on a block to finish up,came up nice,depends on the condition of yours . Real important to clean everthing really well before assembly,good luck and report back,cheers.
had the very same on my 16v, burnt thru the fire ring to coolant. as the engine hadn't overheated I took a chance and just threw a new gasket in. Is still a good idea to get the head checked but the way I saw it worst case all I would have wasted is the price of a gasket/bolt set and a few hours of my life. gamble paid off problem solved and many more months of trouble free motoring
Might be wrong here but, is that heat discolouring on the face of the exhaust manifold on number 4? Might just be a trick of the camera and light but could number 4 be running lean causing extra heat build up and failure of your head gasket?
Yea I noticed that too ,looks like the exhaust gasket on #4 has been leaking and the super heated gasses (steam) have caused that,you notice the difference on number #1 which was also leaking @ the same point but no coolant in that cylinder.
I use 0.05mm on all heads, car and motorcycle. Worth noting if it is badly bent and you have it skimmed flat it will cock your cam journals up (pull them out of true) when you torque the head down. I've only ever seen a handful of heads that needed skimming personally in over 25 years of repairing engines.
thanks for all the replys the heads been gone over with a carbon steel straight edge and 0.04mm feeler gauge a couple of stick points but nothing really of concern but you can never be 100% yes that is discolouring on the exhaust manifold not sure if that's caused by poor manifold fitting or something else I did do a resistance test on all the injectors and they all came back within .1 of each other and will be checking the injectors sprays pattern before its back on road it was in having some work done elsewhere and they said it was running lean so they changed the fuel pump which solved it that was about 8 weeks ago and tbh hasn't done much mileage since I also noticed plug 4 is more oily looking compared to the others, I put that down to its steam clean but not sure
I would suggest you get the injectors tested and cleaned due to the water that been thru #4 and to a lesser extent #3 cyl,its not expensive and good insurance because of those two have have been effected by water....which they really don't like. Sounds like your head is ok,cheers.
When it's all back together, run it for 50 miles and pull all the plugs to check colour. If it's lean you would feel it when driving (surging etc). As said for the cost woth having injectors cleaned and tested.
