Help with Oil Pressure and Temp and Other

[RomanRegal]

Hi, I was running my Regal 24 footer this weekend and found something disturbing. As I push the 250hp 5.7 Mercruiser to 3500 rpm, it seems that the oil pressuure begins to drop and the engine warms up a bit. These are indications I get on the gauges. Neither reading goes into red areas, though the oil presure drop gets close to the bottom of the scale. <br />Also, this season I have niticed that when I throttle the engine up, it seems to hesitate in the 2500 to 3000 range just for a monent and then kicks in and runs well. Thanks for your help. Roman

 

[airman]

Re: Help with Oil Pressure and Temp and Other

How many hours on the engine? My oil thins and the pressure drops when the engine gets hot - that's pretty normal if the engine is getting a bit older. Take a good look at the cooling system though. Check the raw water pump (or just change the impeller) and make sure there is good flow/no obstructions. You might also check the heat exchanger (fresh water cooled) and clean it with CLR if it has any deposits.

 

[RomanRegal]

Re: Help with Oil Pressure and Temp and Other

It is a 1987. One other thng that I noticed is that there is a little too much oil in the pan. I would say about a quart. Maybe a quart and one half.<br />Thanks Roman

 

[akriverrat]

Re: Help with Oil Pressure and Temp and Other

crankshaft running in oil can whip it into foam causing loss of oil pressure. if the oil level increased on its own it is either water or gas getting into crank. water turns oil milky. gas thins the oil and ruins the bearings. if you overfilled it get it out.

 

[RomanRegal]

Re: Help with Oil Pressure and Temp and Other

Thaanks for the reply. One question. What are the problems with the engine if gas is in the crank, or water in the crank.<br />Thanks again Roman

 

[magster65]

Re: Help with Oil Pressure and Temp and Other

Gas in crankcase = fuel pump diaphram leak (or badly flooding carb if there's just a little gas in there)<br /><br />Water in crankcase = cracked casting / blown head gasket / leaky exhaust riser or manifold

 

[RomanRegal]

Re: Help with Oil Pressure and Temp and Other

Thanks for the reply. I have noticed some fuel on the sight hose. In other words it looks like it is coated with fuel. I di not see any inside. Would a broken diaphram in the pump cause the engine to hesistate when throttling up? Thanks again Roman