Help with fitting Double Valve Springs & Collets

[Terrytuned]

Dave if you fit double springs you need the right valve spring cup as the inner spring does not sit properly on the standard valve cups. Terry.

[DaveT]

Hi 
The cups are the correct parts for the double springs, but I'm going to change the springs back to standard as no way would I ever be revving to 5000 rpm or anywhere near. 
I was probably foolish to fork out for a sports block but my original block needed a complete refurb. and I thought it was another way to proceed. 
Saying that I've had 3 years trouble free running but recently I'd noticed a significant drop in performance and upon stripping out the valves the exhausts were very badly pitted with a big build up of carbon, hence the decoke.

[Parazine]

I'm thinking of fitting a LC head when I have finished the decoke 

Beware of fitting a standard LC head if you have enlarged inlet valves! 

Twenty five years ago, I had such a block on a '28 Chummy, where the bores were +60 and incredibly worn. The 14mm plugs in the HC head continually oiled up, so I decided to fit a LC head. It resulted in 4 bent inlet valves as the HC head had been machined out square to clear the valves, which "interacted" with the unmodified LC head. I managed to straighten them again (that's another story!) and continue but it cost me a lot of hours. Such is how we learn...…...

Nowadays, I run a HC head with 18mm plugs.

[DaveT]

Thanks for the warning, my HC head was just a spare head that was fitted to the new block which I believe to be standard bore, but I will take care switching over and carefully check there is no interference or issues,

["Slack Alice" Simon]

For replacing:

I find I am less dexterous than once I was, so split a piece of brass tube and soldered the bits onto the ends of an old pair of long nosed pliers.

[DaveT]

Hi, I take it we are talking about replacing the collets, this method sounds interesting. Please could you post a photo of your modified long nose pliers, I'm all for a gismo to save the pain.

[Ruairidh Dunford]

This is not answering your question to Simon but this is what I use - fabricating something similar would not be too difficult. I use grease to hold the collets in the pliers: https://www.worthpoint.com/worthopedia/v...-245505312

[John Mason]

When you have fitted a different head to your engine and you are ready to start it up. I would turn it over a few times on the crank handle with the ignition turned off. That way you should feel if it is free or if the valves are catching the top of the head without causing any real damage. This also goes for modern engines where valves move down into the bores and can be caught by the pistons.

John Mason

[Nick Lettington]

I put a blob of grease on the inside of the collet and a blob on my finger. This stickcs the collet first onto my fingertip, allowing me to put it onto the valve stem. The collet sticks to the stem and with very little effort, you can slide it round the stem to the back and put the second collet into place. A little rag in the valve chest and a magnet on a stick help if you're a little clumsy.

[Zetomagneto]

Assuming the valve springs still not fitted you could put the proposed head on loosely and see if the valves catch anywhere,