Necessity is the mother of invention

[Steve Bryant]

After spending a lot of time trying to locate a valve seat cutting tool I finally gave up and made one.
               

Either I had to buy an expensive seat cutting kit or spend a lot of time at auto jumbles (swap meets) hoping to find a suitable tool that would do the job.  Since I didn't envisage doing a lot of valve seat  reclamation I opted to make a tool for occasional use.

The cutting bits are shaped silver steel hardened and tempered, with set screws in the body to allow for adjustment as required. A quick test on a spare cylinder block confirms that it will do the job.


If you have made tools or things to allow the repair of your Austin we'd love to see them.
Cheers,
Stephen 

[Ruairidh Dunford]

Very smart Steve, nice work.

[bob46320]

Nice job, a few broken studs as well !! and is that a broken tap in the rearmost manifold hole ?

[Steve Bryant]

Nice job,  a few broken studs as well !! and is that a broken tap in the rearmost manifold hole ?

Yes Bob, that's the way this "spare" block was acquired. I'll get around to fixing it one day
Stephen

[Ruairidh Dunford]

I have removed a number of broken taps, like you have, by shattering them with a sharp punch. Direct hefty whack usually does the trick.

[Bob Culver]

These are handy devices but dangerous in the hands of amateurs. Once gone metal cannot be put back. Ideally confined to narrowing seats and cutting for oversize valves.

For decades I ran a Javelin which cars for various reasons are prone to recession, so had to regularly recut for oversize valves etc. I made a simple single cutter version which is operated against a stop. 

Valve grinding is now questioned. Any attempt to correct the seat leaves a groove in the valve. I made up a set of shafts  with mild steel heads attached. These are selected to close fit in guide and used as laps and regularly set to run true and corrected in the lathe. As with new cars valves then not reground.

[Phil Kingdom]

Woodrow has some useful plans for various simple to make tools flywheel puller an so on.

Here are a couple of head lifters 14 mm and 18 mm or even lift out the engine with them very simple to make just remove the center of the plug by removing the the lip securing the ceramic bit and gentle tapping it out, if you use an 18 mm split plug the job is half done for you, then remove the little bit the spark jumps to on the bottom, drill out the hole to 8.6mm and tap to 10mm then screw in a 10mm Hilti eye bolt. I also drilled a hole though the center of a M10  bolt, this can be used to find TDC on some makes of engine.


  head lifters.jpg (Size: 52.2 KB / Downloads: 590)

[Charles P]

These are handy devices but dangerous in the hands of amateurs. Once gone metal cannot be put back. Ideally confined to narrowing seats and cutting for oversize valves.

If you're smart enough to make a tool like that you're probably smart enough to use it appropriately. 

Charles

[Bob Culver]

Hi Charles

Many get hold of these or cruder versions without making.

Most of my observations are aimed primarly at the not too experienced, who seem to make up many of newcomers.
It is very tempting to narrow wide seats by opening out bore but that is usually a mistake.

Considering that the average Seven has had a myriad valve grinds, seats are often surprisingly good.

My car used to burn valves of old time steel every 6,000 or so and I have reports of same from others in the 1940s-50s.

(common James brand exh valves were of VK+ steel, inferior even to XB, and now only used for inlets.)

[Steve Bryant]

Once I get the new valve guides pressed in I want to insure that the valve seat is concentric with the guide. A minimal scrape with the tool will tell me that.  If it is then fine, I'll just lap the valve in and install.  However, a couple of the seats have some pitting which needs to be removed, hence the making of the tool.

Bob, my policy has always been to remove only the minimal amount of material I can get away with that will give me a good seal. If I don't have to use the tool I won't - but yes
i could certainly ruin the seat by aggressive use, giving a recessed valve with masking and a wide seat which is undesirable. Your concern is appreciated and understood.

Stephen