Valve Job Info

Always enjoy your videos. You didn't mention Neway cutters, any thoughts on them? I suppose they present the same problem as the stone in regard to height. What's the proper way to measure height? Do you ever use Neways or are they more of an amateur DIY tool? Thanks for the videos.

Very good information here.

I'm still in the stone age, and it does take much longer I agree. Never the less I still have some scarry monsters out their prowling the earth.

The 7 angle valve job they just did on my Tesla really made a difference! So pleased with this performance!

Ive done small engine repairs with a sharpie, a stone on a dremel and lapping compound, im lazy so i grab the valve in a dewalt drill and pull it into the seat. But thats also on a twin cyl mower not a performance v8.

Hi Eric, I just watched your video. Thanks for the great info. I have a new set of AFR 195cc SBC heads, still in the box. I'm planning to do a leak test on them, and lap them if necessary. But after watching your video, I'm not sure I'm headed in the right direction. I live in a big city and I'm sure there are lots of shops that I can take my heads to. But I have a hard time trusting people I don't know, s I'm reluctant to turn my new heads over to someone who may damage them beyond repair. I like to do as much of the work myself if possible
I am not a professional, I'm just a guy doing a restored project in my home garage. What would you advise me to do with these heads? Please help . Thank you. Don P.

im old i still use stones to grind mi valves

😂😂 you broke my heart the first 4 minutes but then I remember I spent about $400 on Neway cutters so does that still make me cheap?🥲

The boring head was here before the engine.

Where does the oil get past a Valve, and what fails to cause it, making the cylinder consume oil ?

I bet if you have a lathe you could make an aluminum or brass lap that would thread onto that Sioux stone holder. If your sealing angle is 45 degrees make it 45 degrees. Then load it with lapping compound and it might do a super nice job touching up chatter like you showed. It would of course have to be machined while on the Sioux stone holder so that it runs true within a .0001" or so, and it would probably need to STAY on the arbor at all times. It would probably last a long time before needing refaced. When lapping the "lap" should be softer than the material we are lapping that way it picks up the abrasive by embedding it in it's surface. Aluminum usually works great :-).

Just did a brand new edelbrock head for a 4.0 jeep. Not a single valve didn't leak water. There is no such thing as out of the box.

❤

Hypothetical question... hypothetically speaking, if a person had an engine, rebuilding it on a stand. The engine is mostly stock with minor upgrades (0.030 over + torque plate hone, ceramic coated pistons, rotating assembly balance, a few lbs of boost, head studs, main studs, camshaft replaced with one profiled for low rpm torque) but the engine isn't meant for a few 1/4 mile passes, the engine is meant for 350k miles to 500k miles of heavy and hard towing. If I wanted valves to have maximum sealing during the service life of the engine, should I get a valve job? And which would be best for longevity, not short-term performance. Do 3 angle and 5 angle last the same? Or will one wear out faster than the other?

I paused the video in the middle after you explained the valve seat angles you can cut. In a diesel head, a three angle cut, I assume now, is all that is needed correct?

Heads that flow well one way will also flow well in reverse. On newer, small, multiple valve per cylinder, light springs, this can be a real issue. The old vacuum test may show a good seal...but it's not. There's a better way. Besides the headaches this will give you...there could be some things worth testing and studying.

Hello thanks for the education question i have is should i have had machine shop do valve job on the new 200cc promax heads before using them. THANKS MUCH

Use a Newen BBConturmachine !Never need lapping

Love your content, but respectfully, you unnecessarily threw stones under the bus. Nearly 35 yrs ago, I learned how to PROPERLY form a VJ with stones. And, you're right, it IS an art form. Seats can be formed with infinite combinations of angles (and widths) if you're willing to spend the time with a stone dresser (multiple stones and mandrels) while using a flowbench to 'find' that ultimate VJ. It is liberating to discover that ONE angle is actually better a bit longer than the one next to it, or below it. I'm describing combinations a 'fixed' cutter will deny you.
I'm glad to see you've moved beyond 'generic' cutters for this reason. But are they exactly right, or just 'close enough'? In the past, when sanctioning bodies heavily policed VJ restrictions, the cyl head guy had to find air flow any way possible, so every angle had to be pursued.
The biggest problem I have with single bit cutting, is the monkeys running the machine at factory X, Y, or Z. I have seen exhaust seat runout as high as .009 OOTB ! that's criminal. Cause? Deflection, and in too big of a hurry.
(And while dealing with aluminum heads, that once perfectly sealed VJ has buckled around by the time you've reached 50 runs.)
I have single point cutters, and I love them, but while I'm enduring to keep runout less than my guide clearance, a stone is called upon.

Does the 5 angle cutter leave the proper ~90 percent throat diameter?

Hundreds have been done exactly how you say doesn't work lol along with cutting valve on lathe instead of grinder, seats with a die grinder

14 years cutting seats on a serdi, never have I even thought about using lapping past. If the valve doesn't seal when cut, the cut is wrong simple as that. Also note when Eric dropped the valve onto the seat, the valve bounced. This is because the seat is perfectly round and in line with the guide, if your valve doesn't bounce when dropped, there is an issue. Exception to that rule can be Klines and the close clearances Kliners allow you to run.

Can you do more valve job tech videos. All videos great.

Ever watch David vizard ?

I've been using the Neway valve seat cutters since the early 80's (3 angle)for Atv,Motorcycle and marine Cylinder heads.Seem to work decent and I always leak test my work.i would love to have a serdi,newen or rottler but I'm semi retired nowadays and even if I purchased a nice used machine I doubt I would be working long enough to make it worth my time.ive sent off a few heads to have seats replaced(I do the guides myself)and was very impressed with the work,especially the radius type cut on the exhaust seats,very nice.i enjoy your vids young man,keep up the good work.

Very informative video, thank you.

Guy who does valves jobs for a living tells you you're doing it wrong. Now pay him to do it right.

Ls cheap guy here. I've been working with some factory Ls7 head for sometime now. Had a couple of machinist look at my heads and none of them said there was issue with my valves. I've dropped 3 valves. Looking at the price of having the work done I'm going to do the work myself.

Thankfully with this being a project car, I can take my time. Replace the guides, use a dingle hone to slowly arrive at the right diameter, and lap the valves in. Checking the guides with a bore gauge as I go.

I am chasing titanium intake valves dropping. The issue seems to spur from GM not machining the valve seats to be concentric with the valve guides. Causing excessive wear on the guides. Also keepers wearing on the valve stems to the point the valves fall

Thank for the quality information! Good luck spreading the good word.

Fantastic video & information!

I noticed with the single point cutter it's performance in producing a round (centric) and chatter free is the valve guide clearance . I had used the serdi valve cutter and it was tough to get a even cut . Seemed to want to dig in,and messing things up on me.

Great info for a young engine enthusiast like myself. Thank you for clarifying all the misconceptions and providing us with your wisdom

I want to buy a valve seat cutter head for use with my cincinnati mill. Its kind of like a bridgeport but heavier duty. I just want to use it on tractor heads and these for the most part have valve stems 90 degrees to the deck. I notice some have a ball drive system while some fit right in the spindle with a morse taper or a milling machine taper. Which would you recommend.

Well… 4 minutes in, my feelings are hurt 😅. I put my suction cup in a drill btw.

You ever have a 6.4 hemi head in there to play with?

I don't see how the stone can be blamed for the seat being inserted crooked... if the seat is croocked and one cuts as many angles with stones than with a machine cutter the result will be the same, as both are center on the valve guide.
Only difference will be the time it takes if one needs (and the cost of the equipment)...

Hi Thanks for this. Very informative. what is your opinion on new valves on old valve seats? I understand that if the guides are worn and the valves have been jumping around and is not sealing 100% if the seats are OK can the new valves and seats be married together if you work the new valves to the old seats. i guess what i am saying is ,is this possible to tidy up the seats lightly with the stone.

How long do cutters last? When do you replace it?

Is the bouncing valve test, when inserting into the guide, for motorcycles as well? Seems like if the valve stem slides so easily through the valve stem you have more play in your guide? My motorcycle valves need to be pushed through the valve guide and seal in order to seat.

Обычная операция. Кто в теме, также режет.

How about flow testing different grit level valve lapping?

I have an engine that failed a leak down test and had some bad leaks on the valves. I took the head off and poured water into the chambers. The chambers would hold water but slowly leak and if I blasted compressed air into the ports, I would get lots of bubbles. Yeah, it could have definitely used a valve job, but I just wanted the engine to run right so I lapped the valves using the 3M lapping compound. I noticed that this compound was very coarse and left some deep scratches as was observed under magnification. The water test revealed little tiny air bubbles when I blasted compressed air in the ports. I researched this and found that there are lapping compounds that get very high in grit, like 2000 grit. These lapping compounds were very expensive though and I didn't want to spend so much money on them so I made my own. What I did was I bought some white metal polishing compound from Harbor Freight that comes in a stick for a few dollars. I scraped some off with a razor blade and mixed it with WD40 to form a paste; which worked out quite good after experimenting with many other solvents. After lapping with that stuff, I was able to blast air at 150 PSI into the ports, right up to the back of the valve and not a single tiny little bubble was observed from the pool of water in the chambers. Long story short, the engine now runs like new.

Ok Eric you never said anything about the width’s of the angles. And how important they are. Iam sure everyone would love to hear your thoughts on those angles and widths.

Yepp, I seen it many times where people lap Valves, it drives me nuts. No Lie when I didn't klnow better I use to do it I hate to admit it but yes, I was poor and did what I could. I have used a "ball Stone" on a drill when I was like 15 or 16 on a small engine head and had "good to me" results lol. What I learned is that A "mirror" finnish on the Valve Guide and as you said the Valve Bounce is a good valve job.

Have you ever done stock Mopar 906 heads?,thanks !

Thx Tex

Been a machinist over 20 years now, mostly large industry but always been a gear head mostly BBC. I do most of my own work now and I get by with an old Sioux stone grinder. I’m expanding and would love a real valve seat machine but it’s not justified yet. That said, I can achieve seal without lapping with those tools. I just had to correct concentricity on a pair of Harley heads, the weight of the valve held lacquer thinner with no spring for hours. It just takes more time and dare I say skill?

What valve job would you recommend for out of the box Brodix RR270 heads with CNC chambers?

Thank you for making this video Eric. I'm over in Claremore, not far from you, and have always been impressed with your work. I run a sunnen VGS-20 and I have been using 800 grit to check my valves and seats(I know I'm being to picky) and have been very impressed with how well this old machine holds up against the new Rottlers/Robinson machines. I feel like Sunnen, even today, made the best seat and guide machine out there. Great video man, we have been trying to tell people for years that a lap job with 200grit 🤣 just won't cut it. No pun intended. Lol

Is there a horsepower difference between 2 identical cylinder heads except one set of heads is 65cc combustion chambers and the other set of cylinder heads are 76cc combustion chambers? Both engines have different pistons but both are 11 to 1 static compression? Is there an advantage to using 65cc over 76cc combustion chambers or vice versa?

Before the Serdi Machine and some of the later machines that you could actually do a valve job with all the high end shops used the Hall Toledo Orbital Seat Grinding Machine and the radius dresser ---