Newport Beach-based private equity firm Solis Capital Partners LLC has invested in ICOM North America.

Terms of the investment weren’t disclosed.

Solis typically invests in companies that have revenues between $15 million and $100 million. The latest deal is the sixth investment in Solis’ second fund, which closed in 2013 with $61 million in commitments.

New Hudson, Mich.-based ICOM manufactures liquid and direct-injection propane fueling systems for use by fleet and commercial vehicles.

ICOM was founded in 2004 and is headed by Chief Executive Ralph Perpetuini.

Financial details of the company weren’t available.

Meanwhile, existing Solis portfolio company LEHR LLC acquired EnviroGard, a propane fuel system technology company in Charlotte, N.C.

Los Angeles-based LEHR makes propane-powered engines and tools for home and commercial use. Solis made an equity investment in LEHR in September.