Suncor is reporting higher net earnings in the second quarter despite lower than expected oilsands production due to maintenance down time at its northern Alberta projects.

The company says it had net earnings of $435 million or 26 cents per share in the three months ended June 30, compared with a net loss of $735 million or 46 cents per share in the same period last year, during which a wildfire near Fort McMurray, Alta., disrupted production.

Second-quarter earnings were boosted by higher crude oil prices as well as a non-cash gain of $278 million on the revaluation of U.S. dollar denominated debt.

Suncor says its total production was 539,100 barrels of oil equivalent per day in the second quarter, with oilsands operations contributing 352,600 barrels per day.

CEO Steve Williams said in a news release that the oilsands' performance failed to match expectations in the second quarter, but stronger results are in store now that maintenance for the year has been substantially completed.

Suncor says it is cutting its average 2017 production expectation for its 54 per cent stake in Syncrude by 5,000 bpd to account for a fire and outage there in March, but says improved performance in its non-oilsands operations will allow it to maintain its overall targets.