A large generator has fallen onto a major road in Perth’s north, causing traffic delays and prompting a warning for motorists during their morning commute.

Main Roads WA said the generator was blocking the eastbound carriageway on Ocean Reef Road near Lenore Road in Pearsall.

It is not clear how many lanes are affected, with closures still unknown.

Drivers are urged to exercise caution as traffic banks up in the area.

Main Roads warned traffic was already heavy and advised motorists to expect delays while the debris was cleared.

In Currambiner, a crash has added to congestion on Marmion Avenue southbound at Shenton Avenue.

Lane closures are unknown, with Main Roads warning that traffic is heavy in the area and urging motorists to drive safely.

Further south, a truck breakdown on Tonkin Highway northbound after Great Eastern Highway in Redcliffe is also causing issues.

The truck is in the left emergency lane, with traffic continuing to flow past the scene.