Compression test
Q I recently wanted to test compression on 1.25 and 1.4 engines fitted to 2004 Fiestas using Laser Compression Tester Part No. 2516. Both engines use same type of spark plugs. The plugs screw in perfectly into the adaptor supplied with the tester so the tester without the adaptor should fit in perfectly into the plug holes threads, but I could not screw it in no matter what.
I used the very same tester to test compression on my 1.8 VVT-I Toyota engine, and I had no such problems screwing it in place of the plugs.
Am I doing something wrong, or is this tester is not suitable for this type of engine or plug?
Toyota plugs were gasket types when Fiesta’s plugs were tapered-seat types so maybe this is the reason, but why would the thread not screw in? Is it too short?
Bartosz Kijanski
A The thread is as you mention correct on the Laser 2516 tool, but the end of the adapter is too large to fit in the small spark plug recess on the Ford engines you mention. Laser can supply an adapter, part number 3781 (http://bit.ly/cmnhlpt), which will allow the compression tester to be used in these and other engines.