WINTOOLS Valve Lapping Pro Tool Attachment Car Repair Tool Kit 4 Suction Plates

I used the WINTOOLS Valve Lapping Pro Tool to lap all the valves on my Subaru engine. This tool makes valve lapping quick and easy. The suction cups worked adequately to hold the valve faces with enough grip to lap the smaller exhaust valves and the larger intake valves. It made quick work of each valve. Don't just spin your valves with a drill to lap them! Use a consistent oscillating motion to ensure a durable valve seat. This tool will save you time and effort to lap your valves correctly.

Comes with 4 heavy duty cups and the isolating drill attachment. Clean the cups and the valves with lacquer thinner and away we go! Seen the bad reviews that it doesn’t work. Well it doesn’t come with instructions so I added a tiny vid to demonstrate how it works. This is mechanical lapping which requires more frequent progress checks. If you don’t check progress more frequently, you may need new valves and seats! Overall I think the price is worth it. Not sure if the internal mechanism is made of metal or plastic. That remains to be checked!

Efficient Valve Lapping Tool That Speeds Up Engine Work This valve lapping tool attachment has significantly streamlined my engine rebuild process, transforming what used to be tedious manual valve grinding into efficient, consistent work. The automatic direction change feature alone justifies the investment for anyone doing regular valve jobs. The 8mm shaft fits standard drill chucks securely without slippage, even during extended grinding sessions. The four suction cup sizes (20, 30, 35, and 45mm) cover virtually every automotive valve size encountered in passenger cars, trucks, and even some motorcycle applications. Having multiple sizes in one kit eliminates guesswork and additional purchases. The automatic direction change mechanism works brilliantly in practice. This feature prevents the valve from seating too deeply in one direction while ensuring even material removal around the entire circumference. The result is more uniform valve seating and better sealing compared to manual hand-lapping techniques. Operating speed range of 1000-1250 RPM provides optimal grinding action when used with fine grinding paste. This speed generates sufficient cutting action without overheating valves or grinding compound. Using it with ABRO grinding paste (CT4429) creates an effective valve preparation system. The suction cups maintain secure attachment to valve faces throughout the grinding process. Proper valve preparation with clean surfaces ensures reliable adhesion, and the cups release cleanly without leaving residue when grinding is complete. Build quality appears solid for a specialized tool. The mechanism has survived dozens of valve jobs without mechanical issues, and the suction cups maintain their flexibility and sealing capability after extended use. Time savings are substantial compared to manual lapping. What previously required 10-15 minutes per valve now takes 3-5 minutes with more consistent results. For complete engine rebuilds, this translates to hours of saved labor time. The tool requires some technique development to achieve optimal results. Proper grinding paste application, correct drill speed control, and understanding when to stop grinding all contribute to successful valve preparation. One limitation is the need for a quality drill with good speed control. Harbor freight specials may struggle with consistent speed regulation that this tool requires for best results. Bottom Line: Excellent specialized tool that dramatically improves valve lapping efficiency and consistency. Essential for anyone doing regular engine work or valve jobs. The automatic direction change and multiple cup sizes make this superior to basic manual methods. Best for: Engine rebuilds, valve grinding, automotive restoration, professional mechanics, serious DIY engine work

The only reason I didn't give 5 stars was because the small suction cup came already damage but the tool work very good.

It works. To anyone that doesn't know (I didn't), it works by turning the input drill's rotational motion into an oscillating rotational motion. In other words, the output turns back and forth in the same pattern that you would achieve with a hand lapping tool, just much faster. But you NEED to hold the tool (grey part) stationary while spinning the drill, otherwise the whole thing just rotates instead of oscillating. I did 16 valves, went hard on it (high rpm), and it didn't break or give out. Always use the largest cup that you can fit on the valve. That heavily reduced the amount of instances that I had where the suction cup separated from the valve.

I was skeptical at first, but once I used it, I will never lap valves by hand again! This tool actually works perfectly! It took me 3 minutes to lap a valve perfectly. I’ve been looking for this tool for years. Get it, you will not regret buying it. Plus it held up perfectly.

Works well enough. the only disadvantage i have noticed is that you can't set the drill at medium speed because is difficult to hold the lapping tool making the suction cup to come loose from the valve, you will need to find the right speed that allows to control the movement.

it acts like it works if there is NO load applied, but as soon as you apply it to a valve it stops turning in either direction. Also the suction cups don't stick very good. If the "no torque" problem could be resolved, it probably would work ok.