Timing belt replacement

PATTY1101

MEMBER
2009 SUBARU OUTBACK
2.5L
4 CYL
AUTOMATIC
175,000 MILES

Car lights all came on and car stopped as I coasted to a stop at an off-ramp. The engine made no noise, just simply stopped. Tried to start and starter just hummed - engine would not turn over (valve damage?). Timing belt had snapped. Mechanic said I was in luck, was not an interrupter engine so I am okay replacing timing belt. When came to pick up was told it was interrupter after all and there was engine damage! Engine would not turn over, mechanic sprayed carburetor and engine sounded like it wanted to start. Then said maybe he did not set timing correctly so would re-do the timing belt. Now says it is for sure the engine.
Question: If there was no engine noise after the belt broke, is it possible there is no valve damage? Did the mechanic do more damage by cranking the engine until the almost new battery drained? Thanks for your help.

1 Reply

KASEKENNY

MECHANIC
18,907 POSTS

All Subaru SOHC engines are non interference engines which means if the timing belt breaks it will not damage the valves. The 2.5L is a single overhead cam (SOHC) engine but the 2.5L turbo engine is a dual overhead cam (DOHC) engine. All DOHC engines from Subaru are interference engines. Since you did not note that this was a Turbo engine then I suspect they have not set the timing up correctly.

Also, I am confident of this because if this was a DOHC engine and it lost the belt, you would have heard very loud rattling and clunking when the belt let go as the valves and pistons were hitting each other as the engine slowed down.

I included the process below on how to replace the belt if you would like to review this. However, I would suggest we at least take this to another shop for a second opinion before you pay for a new motor.

Let us know what questions you have. Thanks

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