Discussion and questions related to the course Engine Building Fundamentals
I do not know if this is in right section . I personally build a lot of engines and always clean all the items regardless if its new or not . One of my co workers has just built a new engine which he didn't see that where one of the exhaust bolts go one of the threads was gone and was forced to tap and use helicoil . Although he had everything covered a little bit of metal shaving got through and he was lucky that the valves were closed on 1 cylinder and a little bit open on the one next . He is not sure if anything went through the one that was slightly open but regardless tried to clean it as good as possible and blew air through also (he did that on all cylinders just in case) . But on the cylinder that is closed you can see 1 or 2 really small metal shavings . He is thinking of removing the headers again and spark plugs and crank it a few times just in case there is more and hopefully remove those 2 stuck shavings .
Any other recommended ways ? Will this cause much damage if there is indeed something that he didn't see ?
At a rough guess, it will depend on the shavings - if they are very small, they might get trapped between the piston crown and the head and, if a bit bigger they could get caught between the piston and head in the quench area?
Could he make up an adaptor to fit an inline to the spark plud hole and blow air through it with the exhaust open?
The 'best' thing to do would be to pull the head and so be sure but...
The next time, use some oiled lint free cloth pushed down past the area being tapped - oiled and lint free means any little particles will stick to the cloth and lint free means it will come out cleanly. I've done this a number of times without problems (as far as I know, at least ;-) ).
Thats a nice trick . I will keep that in mind . He had masking tape on each cylinder but when he blew air to clean the hole somehow it went pass . But I will let him know also for that suggestion . The shavings are really small as its from the tapping that he did . Luckily he uses makita thread paste and the majority of the shavings get stuck on the paste on the tap .