Amtrak has suspended its Acela high-speed train service in the U.S. Northeast. The company is concerned about cracks in the Canadian-made locomotives, a problem that could derail manufacturer Bombardier's reputation.

All 18 Acela locomotives are going through a thorough inspection, after cracks were found on shock absorbers on three of the trains. The cracks could cause a wheel to release and fall under the train, leading to a derailment.

"We don't know right now what the cause is, whether it's lateral stress, a design flaw, or the workmanship," Bill Schulz, an Amtrak spokesman, told ABC News.

The cracks are the latest of a slew of problems plaguing the Acela model. In July, Acelas averaged one mechanical breakdown a day. Malfunctions ranged from serious -- the braking mechanism froze on one train -- to inconveniences like sticky bathroom doors that briefly trapped passengers inside.

The trains were built by Montreal-based Bombardier and its partner Alstom of Paris. They are capable of running at speeds up to 240 kilometres per hour.

Bombardier says its equipment is not to blame for problems; Amtrak's rail infrastructure are at fault, they allege.

For now, Amtrak is diverting passengers from the express service to the Acela Regional and Metroliner, which travel the same route between Washington, D.C., New York and Boston, only more slowly.

The rail service says that any Acela trains found to not have the defect will return to service on the route.

Even before the latest problem, Amtrak's president David Gunn -- a former general manager of the Toronto Transit Commission -- said he would never order another Acela Express from Bombardier.

Amtrak had initially ordered 20 of the Acela trains, but last month, it refused to accept the 19th set because some of the agreed-upon modifications had not been made.

Gunn is meeting with Bombardier to determine who is responsible for the repairs.

Jacques Kavafian, a transportation analyst with Octagon Capital Corp., said Tuesday he thinks it will take a long time for the two sides to resolve their dispute.

"I'm not sure how it's going to end up. But I think we're going to hear this for a long time,'' Kavafian said in an interview on Report on Business TV.