Going back a couple of posts you may recall i had a small hole in the side of the engine caused by water freezing and expanding with such force that it blew out the side of the block.
You will remember I had left the metal filler to dry thoroughly before attempting to drill and tap the holes for the bolts. The brass plate was already the right shape so I now measured out a neatly spacing row of punch points around the plate and drilled a 4mm pilot hole wherever i wanted a bolt to be. Using these pilot holes as a guide, I then drilled a 4mm hole into the side of the engine. Most of the holes were made as you would expect, a cobalt drill making short work of the cast iron. BUT 2 of the holes needed to be where the previous owner had applied weld to his patch panel and his ‘repair’ had made the metal so hard that it blunted TWO brand new cobalt drills whilst barely making any impression. It was with some sadness that i was now forced to drill holes off line with the other bolts to avoid this super hardened material. This results in a job that is less neat and certainly not what i had envisioned. Never mind – such is life. A repair that holds back water is more important than the asthetics of having 2 bolts slightly off line. The exhaust manifold hide the repair anyway – but i like a ‘proper job’.
The next challenge was making a gasket that was waterproof. Obviously i can’t buy a ready made gasket for this but manufacturing one is not so hard. I just had to find the right material. This part of the excercise was a little silly… I found a company that made said gasket material in 1m square sheets and i needed around 120mm x 120mm maximum. They said they could provide a sample which seemed like a good idea so i asked for a price. £10 they said plus £10 shipping. Seriously £20 for sample? I popped onto your favourite online auction site, found someone selling an off-cut of the same material and bought a 200mm x 200m piece for £6.50 delivered. How can eBay be so much cheaper than buying direct from the supplier. The salesman is missing a trick i think and £10 to put a flat sheet inside an envelope is just taking the proverbial.
So below is the gasket cut to size and held in place using blue Hylomar – my favourite sealant. The holes were made with a punch, intentionally slightly oversize because you can’t see where the middle of the hole punch is
It was then simply a case of bolting the panel into place. I had thought of keeping it natural brass, but i didn’t like the fact the bolts were not neat so it got a coat of paint to match the engine. I then filled up the engine with water and left it a week – no leaks. So thats that job done. Moving on…