Engine Rebuild (Part 4) - Fitting The Valves

By mid September 2017, and after an initial clean up, I had been soaking my DX exhaust valves in Mek pretty much since mid August. This loosened some of the burnt on muck - but not nearly enough. In the end I had to resort to using my wire wheel to clean them up. I was very glad I did as it did a great job. I was very careful to avoid going too far up the shaft of each valve with the wheel as I did not want to introduce scratches.

At the end of September 2017 - while researching cylinder heads and valves -  I was lucky enough to find a set of NOS DX inlet valves for my 1968 car.

New Old Stock Inlet Valves - October 2017

These were the earlier 47mm diameter valves, BUT with the three groove cap and collar. They were only fitted for about 15 months between May 1967 and July 1968. Result! (See my other post on DX valves for more on this).

September and October were spent getting the cylinder head ready - including vapour blasting, skimming, fitting new valve guides and having the valve seats re-cut.

By mid November it was starting to come together: I  had my cylinder head, my valves ready and all other associated parts had been thoroughly cleaned and oiled. I was ready to go.

Underway - 12 November 2017

I spent an afternoon lapping the valves. This process was not nearly as long-winded as I thought it was going to be - possibly because half my valves were new and - more likely - because the all valve seats had been re-cut. The objective is to keep lapping until you have a solid, clean ring showing on valve and seat - meaning the surfaces are flush and a good gas seal. The tone of the grinding note changes as you reach that point. It was really quite satisfying. After lapping I carefully wiped up all traces of grinding paste.

With my new valve spring compressor, I was able to make quick work of re-fitting the valves.

Fitting The Valves - 12 November 2017

Compressing the Springs to Slip the Collars Around the Stem

Working methodically, I was soon done. I was very pleased with the results and finished the day by re-fitting the tappets. I couldn't resist sitting the head on the block and adding the push rods.

Valves and Pushrods - 14 November 2017