As many of you already know, several Goodson Tools were recently featured on Horsepower TV (part of the Powerblock on SPIKE).
This episode, called “Budget Cylinder Head Refresh” shows a quick overview of a valve job, including how to repair guides with our Bronze Liners. You’ll also get to see how easy it is to grind your own valves.
Watch the video online, then check out the Cylinder Head Supplies section of our website for the tooling you’ll need.
By Jim Tapp
Goodson Tech Service
Is the grinding or cutting of valve seats taking way more time than necessary? Does it seem that hardly any of the seats are finishing on the same plane? Can’t seem to get a handle on what happened?
Is it bad leveling?
A defective cutter?
A non-concentric pilot?
Wow, we have all kinds of possibilities! And after we have eliminated one cause after another, we give up. Hey the seat’s good enough!
Not knowing the real problem, it becomes a living nightmare, head after head after head.
Ask yourself again, what have you forgotten? What else could be causing this problem? It’s easy to overlook the obvious – Replacement thick wall valve guides.
It would be wonderful deal if all replacement false guides were manufactured consistently and concentrically, but they are NOT. It has been my experience that it’s about a 50-50 dice role. Getting cast replacement guides to check out at a T.I.R. less than .001”, as they are guaranteed to be, doesn’t happen. Please don’t get me wrong, there are many guides manufactured perfectly, but they are usually a little more costly. Like always, you get what you pay for, hopefully.
How the heck do I check valve guides quickly and accurately?
With the Goodson Valve Guide Run-Out Gauge, of course. It takes a little over a minute to check a set of 16 valve guides for concentricity on both ends, after a short set up time. The part numbers for the tool are: VRG-375, VRG-385, and VRG-437, dependent on your pilot top size. This allows you to be in control of your valve seat work.
Need a little more information about this or any other Goodson tool? Call the Goodson Techxperts at 1-800-533-8010 or shoot us an email.
Using bronze liners is one of the fastest and easiest ways to repair valve guides. Here are a couple of tips to make it even easier.
Use a centering cone
With the cone centered on the existing valve seat and the extended pilot of the boring reamer located in the existing guide, boring alignment is assured. With accurate alignment of the new guide, minimal seat work will be required to finish.
Use the correct size centering cone
The centering cone must fit the valve seat properly so using the correct size is essential. This is not a one-size-fits-all tool. Goodson carries 60° centering cones in diameters from 1” to 2-1/2” so you can find one that will fit the seat you’re working on. If you have a cone that’s too small for the seat it could slip right through the opening and if you have one that’s too large, the side of the chamber could interfere or you won’t have enough of the cone in the seat area for it to be stable and centered.
Image at left shows how the centering cone locates on the valve seat. In some chambers, particularly in small heads, the wall of the chamber may interfere with the placement of the cone. In this case, you will need a smaller cone so that it aligns in the seat correctly. Use the chart below to select the correct size centering cone for your application.
| Nominal Size |
Part Number |
Top-Bottom Size |
| 1.00” | CL-6310 | 0.970” – 0.730” |
| 1.25” | CL-6308 | 1.230” – 0.740” |
| 1.50” | CL-6306 | 1.475” – 0.805” |
| 1.75” | CL-6304 | 1.730” – 0.860” |
| 2.00” | CL-6302 | 1.950” – 0.875” |
| 2.25” | CL-6300 | 2.230” – 1.000” |
| 2.50” | CL-6312 | 2.550” – 1.875” |
Use the correct tooling for best results
Several companies offer tooling for installing bronze liners and for the most part the tooling and the liners themselves are fully interchangeable with one important exception. Goodson offers liners for 5.0mm and 5.5mm guides and these two sizes require you use Goodson tooling.