strange volvo sx 5.0 overheating problem

[ZZ3Astro]

Hi All,

New to the forum but not to boating.... well I did take a long break but I just purchased a 1996 Sunbird Corsair 20' with a Volvo 5.0L and SX drive. Long story short, I knew it had some problems with the cooling system but I'm not overly familiar with the newer Volvo drive... so I thought I'd run this by everyone here to make sure I'm on the right track...

There are two concerns with the cooling system:

1> If I connect an engine flusher to the outdrive and hold the cups against the drive, the water comes out somewhere around the host that connects the drive raw water feed to the transom plate... it's definitely coming out right around the end of the hose on the drive side. It's nearly impossible to see in there and the hose clamp is turned at an angle I can't get to. It seems a little looser than I would make it but not falling off loose. I gotta get that service manual I saw at the store yesterday!

2> A much more serious problem, if my thinking is correct, is that if I tilt the drive up, the water begins running out of the exhaust hole at the base of the transom plate. Top side inspection reveals no water flowing through the raw water pickup. I can push on the exhaust bellow and the water will stop flowing for a few seconds until it rises higher, so I know it is coming from the drive side. I can't imagine there being a good reason for this. I checked the raw water inspection plate (next to where you access the shift cable) and it looks in good shape there. If I'm looking at the diagram right, the most likely source of a problem like this would be at the top of the foot assembly.

The boat runs 160-170 at idle and low cruise, 190-200 at 2500 rpm and will quickly go to 200+ beyond that.

Thanks for any info...

Steve

[ZZ3Astro]

Well I couldn't take the pressure any longer. I removed the drive and found the problems... and there are many, all traceable back to the shoddy mechanic the previous owner spoke so highly of. There is a rubber block that seals the raw water between the upper and lower parts of the drive.. that block was improperly installed which caused it to be completely in the exhaust stream, which dried it out and made it shrink, allowing the exhaust hot water to enter the raw water pickup. I fed water directly into the raw water pump and the engine runs 150 now at 5000 rpm all day. However the raw water pump is now leaking, traced back to a stripped screw that was being held in with orange rtv. Since the pump hasn't seen enough water to make any pressure for all this time, the steady feed of water made pressure and pushed the bolt out of the stripped hole.

This is turning into a $6000 lesson, not counting the money I may have to put into it to fix any damage that may have occurred. Ouch!

steve