1999 Subaru Outback 2.5l 4 cyl
- Replaced both head gaskets & timing belt, had the heads freshened up and machined (just a little). Did NOT replace the water pump because [reasons].
Problem: reinstalled the motor last night and stared it up. Seems to run fine, but it is making an alarming rattly-scrapy noise. It sounds a bit like a metal shroud rubbing against one of the pulleys. Took that shroud off but the noise persists. It doesn’t sound like it’s coming from deep inside the engine, and it really doesn’t sound like any sort of impact (say, between pistons & valves from a bad timing belt install).
I did put oil in it, and the noise began as soon as the engine started. It does not have coolant in it yet. I know a power steering pump will growl when it gets hungry, is there any chance a water pump would be noisy if it’s dry?
Tonight’s troubleshooting will be to add coolant and then unbelt the AC pump, then alternator to rule out loose internal bits. Any other ideas?