OTC 5021 Universal Diesel Compression Review

Item works as described. I have seen many complaints that the needle was not set to 0 on arrival. In the lid there is a button for 0 from the meter. worked great for my 2004 6.0 Powerstroke

is a good compression sensor. It's not easy to find 1/8" quick connect adapters, but this gauge comes with a 45 degree quick connect adapter with a built-in one-way valve. Some brands of head adapters have a valve core, but OTC does not, and you need this valve to properly measure compression.

I used this product to test the compression on my 7.3 liter Ford Powerstroke diesel car. Used the correct OTC adapter and it worked great on all 8 cylinders. It feels firm and seems to hold up well under pressure. The only minor downside was that the sealant used to hold the pieces together tends to get wet and rub off your hands and clothes on first use. But still five stars because it looks really good and does its job well.

If you have a 7.3 Powerstroke these cheap universal/special diesel compression test kits are a waste of time and money. I have one that says on the box that it works with Powerstroke 7.3 and it comes with all sorts of adaptors, including the right thread for my glow plug holes, but the quick connect doesn't clear the notch in the head casting. If you see it, nothing will happen unless it's custom made - it should be long, with the end of the sleeve many inches above the threads. An OTC adapter…