View single post by Esprit2
 Posted: 11-28-2021 05:02 am
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Joined: 05-01-2005
Location: Minneapolis, Minnesota USA
Posts: 572
The fuel pressure IS high. Install an inline fuel pressure regulator as close to the carb inlets as practical, and set it to 2.5 psi. However, that's a side-issue and doesn't explain why cylinder #4 isn't running correctly.

Compression pressures are in spec. Jensen-Healey specifies checking the compression on a cold engine, and calls for a minimum of 7.58-8.96 bar (110-130 psi) COLD.

Lotus specifies checking the compression on a hot engine, once it's up to full operating temperture. In that case, with the same 8.4:1 compression ratio, they spec 10.2-11.6 bar (150-170 psi).

For both the J-H and Lotus compression tests, the throttle is to be held fully open, and the engine cranking at least 200 rpm (ie, battery fully charged, or use jumper cables).

Tim Engel

Last edited on 11-28-2021 05:04 am by Esprit2