1975 140 hp mercruiser problem.. uh oh

[thehickfarmer]

well guys.. i have a problem. i'm leaking oil. AND BAD !. i was running the motor for about 5 min until i see smoke from the back. and i'm thinkin FIRE! well no. turns out the oil pressure sensor blew right off . oil was leaking quick. and then i started hearing a tinging noise. now the motor was stil cool at the time. i mean it was warmed up. but nuttin a 3 year old coulden't take. so i'm askin could it eb that my lifters are scrwed??? and if my cranshaft bearings are gone. would the motor even run then ???

 

[Don S]

Re: 1975 140 hp mercruiser problem.. uh oh

You probably heard the lifters getting air in them and causing them to collaps a bit, which will cause them to make noise. Fix the leak, fill it with oil and start it up. Should be fine as long as you don't hear any HARD knocking, clicking will stop, Knocking will not.

 

[cc lancer]

Re: 1975 140 hp mercruiser problem.. uh oh

If you have not cranked the engine since the problem occurred do the following.<br />Remove all the plugs and spin the engine to get oil to the bearings, do this several times, you should get app. 20 lbs. of pressure just spinning it with the starter. Let it spin, battery's and starters are cheaper than engine rebuilds. If it is not damaged you will get oil every where it needs to be. <br />My present family boat sat for 12 years before I got it, I spent hours spraying oil in the cylinders, and spinning it over. My compression is on factory specs. and runs like new.

 

[thehickfarmer]

Re: 1975 140 hp mercruiser problem.. uh oh

well i don't think like 2-5 min is enough to kill the crankshaft bearings ???.. and also. can somone inlighten me on what do these lifters do?

 

[Don S]

Re: 1975 140 hp mercruiser problem.. uh oh

You can take the spark plugs out and you can crank the engine and build up oil pressure. But till you start it, you won't know if it's going to make noise or not. Or if it will stop making noise or not. (once the lifters fill with oil not air, they will get quiet again). When you start it, if you get oil pressure within about 5 seconds or so, you will be fine (unless you have a heavy knock). And squirting oil in the cylinders will not get oil to the bearings, trust me. If you damaged the bearings and crank, one more startup isn't going to do any more damage.<br />Unless you want to completely dissassemble the engine and take a look at all the parts.

 

[thehickfarmer]

Re: 1975 140 hp mercruiser problem.. uh oh

so your saying even with bad bearings. you can still start the motor ?

 

[Don S]

Re: 1975 140 hp mercruiser problem.. uh oh

Almost forgot. <br />What Lifters Do.....In a nutshell.<br />The lifters ride on the cam shaft and push the push rods that push the rocker arms that open and close the valve to let fuel in, exhaust out, and closes both valve so you have compression.

 

[Don S]

Re: 1975 140 hp mercruiser problem.. uh oh

Yes, even with bad bearings you can start an engine. But if you don't know what you are listening for it isn't going to help.<br />You might find a marine mechanic to at least start it and listen to it and hear if anything major is wrong.

 

[thehickfarmer]

Re: 1975 140 hp mercruiser problem.. uh oh

well i am 14 years old. this boat was given to me by my dad. this isen't the 1st time this happend. it actually all happend with all 48 hours. the 1st time. it started tinging. so i figured the lifters where being funny. so i put oil in it , put the muffs on the drive. started it . and the noise was gone! and now it is making the same noise so i'm hoping it is this again. but if it is the bearings. what are the price from a marine mechanic to fix this ? and i'm guessing your gonna be telling me us prices corect

 

[cc lancer]

Re: 1975 140 hp mercruiser problem.. uh oh

And squirting oil in the cylinders will not get oil to the bearings, trust me.<br />And I didn't imply it would, because my engine had sat for 12 years, I knew there was possibly rust in the combustion chamber and I don't want to risk breaking a ring.<br /><br />thehickfarmer<br />Since it is unknown how long the bearings were without oil, the oil wedge between the bearing and crank could have have been completely removed, creating a dry metal to metal situation.<br />Possibly the oil on the cylinder wall was eliminated, creating a dry situation.<br />With the explosive force generated in the combustion chamber driving the piston/Rod down and there not being the oil wedge between the rod bearing and crank, bearing damage can occur.<br /><br />can Simone enlighten me on what do these lifters do?<br />They help open and close the valves.

 

[Don S]

Re: 1975 140 hp mercruiser problem.. uh oh

OK, CC, you said:<br />

Since it is unknown how long the bearings were without oil, the oil wedge between the bearing and crank could have have been completely removed, creating a dry metal to metal situation.<br />Possibly the oil on the cylinder wall was eliminated, creating a dry situation.<br />With the explosive force generated in the combustion chamber driving the piston/Rod down and there not being the oil wedge between the rod bearing and crank, bearing damage can occur.<br />

Oil Wedge?? New word for me, but Ok.....Now, what do you recommend he do with the engine??????

 

[cc lancer]

Re: 1975 140 hp mercruiser problem.. uh oh

Well Don;<br />I was in NASCAR racing for 12 years, ending on the Modified Tour, and with 50 years experience working on internal combustion engines. This is a common term used by NASCAR engine builder to identify the oil firm between the bearings and crank, maybe not used that much in your part of the world. <br />One of the biggest reason for knocking the bearing out of an engine, is cranking them after sitting for a long time, or extended run time with no oil pressure.<br />As recommended by you and my self on this post, repair the leak, put in oil, spin the engine to get oil through the engine, put in the plugs and crank it up.<br />You have your opinion, and I have mine based on my experience with engines. But many engines are ruined because people get in to big a hurry to crank them up.<br />thehickfarmer:<br />We are here to help you learn how to fix your engine, every one starts by asking questions, that how they learn. So ask away.

 

[Don S]

Re: 1975 140 hp mercruiser problem.. uh oh

Well CC, why did Jimmy loose 3 and Jeff 1 in only a month ??? <br /><br />Never mind, answer not even expected or required.<br />Have a good evening my friend

 

[thehickfarmer]

Re: 1975 140 hp mercruiser problem.. uh oh

thank you gusy. i will see this weekend. please pray that is as just my lifters colapsing lol. whats the price for a mechanic to fix the bearig isue ?

 

[thehickfarmer]

Re: 1975 140 hp mercruiser problem.. uh oh

oh. and sorry about the spelling. it's 6:00 am

 

[thehickfarmer]

Re: 1975 140 hp mercruiser problem.. uh oh

so anyone know how much the reapair would cost ?