Review on 💉 Lang Tools Diesel Compression Adapter TU-15-26 for Injectors by Mark Glass

great product I used it on my 2005 Cummins Diesel. Some information on how to use this article. The Amazon photo of this item is outdated or incorrect. A white Teflon washer should be fitted to the small end of the tool. It can be saved with a small dab of lube. The larger end does not need to be sealed. Washer (according to the manufacturer's verbal instructions, I called them), if the sealing washer is not moved to the small end of the adapter, it will not seal the injector orifice and therefore will provide a low compression reading. I found that adding a rubber o-ring to the larger end also gave higher compression ratios. The O-ring used had the size "P 12". Metric Buna O-rings 11.8 x 2.4mm. I think the manufacturer should have included 2 teflon washers, one for each end. If you search the web at the manufacturer's website it will show an updated photo of the sealing washer in the correct position, langtools.com and then search for TU-15-25. I hope this helps someone. Also, be sure to remove all injectors first before performing a compression test. This gives better results as the starter motor can spin the engine faster when all the injectors are removed.