1999 Volvo Penta 7.4 GIPWTR and a DPS M 1.78 41120685320 / 3868912
Before 1st time in water this summer I had the lower unit oil changed, impellor changed, engine oil/filter changed. Put boat in water and it overheated. Ran hot (about 230) for about 5 minutes before I new it. Got back to the dock and saw an oil slick coming from the lower unit as well. found lower unit oil coming out on top of the exhaust fin. Marina ordered a new o ring kit for the leak (which fixed it) and replaced the impellor and o rings again. Same heating problem. Pulled the output hose from the raw water housing and it's barely moving any water. Flushed all the lines, replaced the thermostate and circulation pump (it got damaged when it ran hot) and all seamed fine. But, when I crank the boat I have to feather the throttle in neutral to get the raw water pump to start moving enough water. Once it primes itself all works fine, however let it sit (up on the lift out of the water) and don't try to feather the throttle and it will not pull enough water to cool the engine. Seems like I'm pulling air somewhere between the raw water pump and the lower unit intake. When the boat stays sitting in the water I don't seem to have a problem sucking enough water up to keep it cool and once it starts moving water (primed) it will stay that way all day. I followed the hose back to the transom and all seemed fine, so my question is how is the line routed down through the outdrive to the pickups? when they changed the lower unit oil could they have created another problem by pulling a hose loose inside the outdrive?
Before 1st time in water this summer I had the lower unit oil changed, impellor changed, engine oil/filter changed. Put boat in water and it overheated. Ran hot (about 230) for about 5 minutes before I new it. Got back to the dock and saw an oil slick coming from the lower unit as well. found lower unit oil coming out on top of the exhaust fin. Marina ordered a new o ring kit for the leak (which fixed it) and replaced the impellor and o rings again. Same heating problem. Pulled the output hose from the raw water housing and it's barely moving any water. Flushed all the lines, replaced the thermostate and circulation pump (it got damaged when it ran hot) and all seamed fine. But, when I crank the boat I have to feather the throttle in neutral to get the raw water pump to start moving enough water. Once it primes itself all works fine, however let it sit (up on the lift out of the water) and don't try to feather the throttle and it will not pull enough water to cool the engine. Seems like I'm pulling air somewhere between the raw water pump and the lower unit intake. When the boat stays sitting in the water I don't seem to have a problem sucking enough water up to keep it cool and once it starts moving water (primed) it will stay that way all day. I followed the hose back to the transom and all seemed fine, so my question is how is the line routed down through the outdrive to the pickups? when they changed the lower unit oil could they have created another problem by pulling a hose loose inside the outdrive?
