Better but still running got

["Aquahaulinass"]

So after the back flush I put the boat back in the water still had high water pressure it would fluctuate between 15 and 25 psi at idle speed and at high speed would hit 35 psi. The motor didn't over heat but I didn't let it. Under power the temp gauge would creep up to 3/4 then I would back off and it would go back down to 1/2. Temp buzzer never came on. This is the first boat I've had with a temp gauge so I don't know if this is normal. I think I may still have a blockage some where but before I pull the power head I would like to get others opinion. Motor is a 87 black max 175 that was built by a guy in fon duloc to be a 225. With all the sand and gravel I got out with the back flush makes me think there can be more in there. Any suggestions would be greatly appreciated
Tx mike

[22R]

Tilt motor as far forward as it will go to almost horizontal. With lower unit off shoot compressed air up water inlet tube and also back though pee hole and exhaust ports best ya can. If that does not get it after all you have done I would pull the powerhead and clean adapter plate and run weedeater string through block water passages.

22R

[Dave Strong]

So after the back flush I put the boat back in the water still had high water pressure it would fluctuate between 15 and 25 psi at idle speed and at high speed would hit 35 psi. The motor didn't over heat but I didn't let it. Under power the temp gauge would creep up to 3/4 then I would back off and it would go back down to 1/2. Temp buzzer never came on. This is the first boat I've had with a temp gauge so I don't know if this is normal. I think I may still have a blockage some where but before I pull the power head I would like to get others opinion. Motor is a 87 black max 175 that was built by a guy in fon duloc to be a 225. With all the sand and gravel I got out with the back flush makes me think there can be more in there. Any suggestions would be greatly appreciated
Tx mike

You can back flush as you did and get a lot of stuff out of the block, but will never get the crap out of the exhaust adapter.

Dave

[flabum1017]

check the poppit valve for blockage, remove it and backflush it there with the lower unit and thermostats off. flush it all ways back and forth. if that doesn't do it, you'll have to pull the heads, pull the exhaust cover and lift the powerhead off the mid and do a thorough cleaning.

[Merc 2.5]

Poppet valve 1st if u haven't changed it , if no go , it's in adapter plate ,if that much sand and stuff came out
Pretty much what Dave said