Not Another Valve Job!
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 Published On Jun 1, 2021

In this episode I install brand new valves into an existing valve seat. If this is the fix you're trying to do, this is everything you need to check, and how to get this job to go your way. Adding only an intermediate expense of tooling to check your work is how you can chase down and pinpoint the tiniest of leaks in your valvetrain, or discover problems that would reveal you're wasting your investment of time and energy. This extra time and attention to detail can make a dramatic impact on the overall performance and longevity of the part.

Here's a video of an actual valve job being performed by a machinist. He demonstrates how he compensates for the imperfect world we live in with his machine setup and Bob Ross'd it:
   • Cylinder Head 201 - Radius Cut Valve Job  

If you plan to clean up and re-use your old original parts, go watch Valve Job Basics. It covers all of that stuff that I don't have to do here. I pick on it in this video, but really, I love it. It's a good video.:
   • Cylinder Head 105 - Valve Job Basics  

You need a valve job if:
• you can't meet the valve or seat contact specifications in your service manual
• you have bad valve guides
• you have bad valve seats
• your valves land crooked on the seats, or don't seal.

Nothing I do in this video will fix these issues, it will only reveal them in extreme detail. You will have no question. If any of these things happen on your part, it needs a valve job. And if you need to replace valve guides, include the cost of the valve job, too. This is how I get the most if there's a seat left to work with.

The tools used here to test both the guides and to vacuum test the head ports combined would be between $100-$400 depending on whether you make them yourself or buy a package kit deal that comes with everything you need plus some sort of vacuum pump. So that tool estimate assumes that you already own tools like an air compressor and have a set of micrometers available to you. You can pay however much you want, for tools, but you can see here what works, when you need expensive tools, and when you don't.

The JB Industries Platinum 7cfm vacuum pump alone in this video is a $600 pump all by itself. And you can see just how unnecessary it is for this kind of work. The example it provides you with here is priceless, though; just like the cheap little $20 Venturi that ends up being the perfect tool for this job. Just make sure your compressor can keep up with its demands of the Venturi, and suddenly it becomes really easy to hit the low end of that tool investment scale. 30-gallon or bigger usually can. Needs a 4.2 cfm recovery rate to keep up with it. Just saying.

The results on the vacuum gauge demonstrate what level of perfection is easily achieved with a meager tool investment, and a basic understanding of the process. I showed you how to chase the leaks, but I didn't need to show you me doing that on the whole head and then cleaning it back up again. A little extra tooling combined with the persistence and sweat equity from the mechanic can go a really long way in the finished product Once this skill or knowledge of the tool is acquired, you can achieve the best possible results for a lifetime whenever all other factors are correct. I felt it was necessary to point out how the vacuum sources are related to the test. All you need is a cheap AC hose, and some 3/16" sized barb fittings, A 1/4" NPT tee block, a cheap vacuum gauge, a set of port testing pads and some Teflon tape. You can buy these hand-crafted hand-pumped vacuum kits on eBay that come with almost everything you need in exchange for a little extra cash... you can buy just the vacuum plate kit by itself, you can make one yourself... I wanted you to understand where it all fits in. 23" of mercury on the hand pump isn't 23" of mercury on the Venturi or the air compressor. It still works. And you should still try to hit 23" of mercury on that thing, you'll do the best valve work of anyone around you.

Sometimes we get lucky. This is one lucky Galant VR-4.

Here's a place where you can make a direct impact on my production. One that could become life-changing for me. I don't have any perks in place yet beyond early access to new uploads, and your names in the credits, but it's coming. The one thing we're always trying to save that's always getting away... You can sponsor my work, these projects, and all the tools I get to do it with by visiting me at   / jafromobile  . I owe everything about my current capabilities to those incredible people.

Now go do great things! Save these old gas burners. We're going to need them some day!

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