Hi, I have a problem that has been driving me crazy. I have a 2003 merc 2 stroke 30 racing modded in New Zealand for surf rescue/racing. I got it about 4 months ago and the last owner didn't care about it at all, pretty much the only thing done to maintain was to flush it right after it got out the water. Now when I run it for a while, it overheats, even though there is a stream coming out the back the whole time. The impeller looked fine, I replaced the seals around it, but the cooling system around the impeller had a bunch of what looked like maybe calcium buildup that came out with a toothbrush, but I think that is all over the innards of my cooling system where a toothbrush won't go.
How do I fully clear all that out from the system as flushing and running don't work, or do you guys think I have another issue?
PS I always flush after every use. And the old owner always ran it through the surf, off the beach, so there was a decent amount of sand going through it.
How do I fully clear all that out from the system as flushing and running don't work, or do you guys think I have another issue?
PS I always flush after every use. And the old owner always ran it through the surf, off the beach, so there was a decent amount of sand going through it.
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