How bad is it DOC?? PIC

[jleus]

Re: How bad is it DOC?? PIC

Boatster, Have been watching this post and in re-reading have never seen where you determined why the oil injection failed. I eliminated the entire system on mine during a rebuild resulting from what I believe to be oiling failure. Toooooooo many rubber to metal transitions for me!! If it dies again and you part out, run it on EBay..... I am interested in any broken dt-25c/30c, complete or parts, I can get my hands on. Very popular engine in my area.

 

[jafa]

Re: How bad is it DOC?? PIC

Hi Boatster<br />Assuming no futhur expense required. Could you do a rough cost on all the parts and hired labour. Helps to determine when a motor becomes uneconomical to repair.

 

[boatster]

Re: How bad is it DOC?? PIC

PikeFisher, thanks. We all love happy endings. But as you may know its not over till the fat lady sings <br /><br />Jleus, I totally understand what you mean by the oiling system. From now on I will be adding a little oil to the gas beforehand as well. What caused my oiling system to fail was (I think) #1 the oil tubes have hardened and lost the suppleness to keep a good seal and #2 the oil flow sensor was not sensative enough to detect the air bubble going through (works via vacuum). From what I noticed on my engine if you get an air bubble you can't just open the bleeder on the pump, you have to open the cap on the fill tank. This makes me suspect that air is being sucked somewhere upstream from the pump rather than creating a vacuum and triggering the alarm or pulling down more oil. Something like that, either way I'm going to replace the oil lines theyre like old arteries, stiff and worn. BUT if it does die again I will be parting it out on http://www.blujay.com <br /><br />ROckhopper, The cost wasn't too expensive afterall. My mechanic charge 1/2 hour to hone the block and take measurements $35. The parts: 3 pistons, 3 rings, 3 piston pins, 3 piston bearings, head gasket, other misc parts cost $270. Of course I also purchased a manual, sealants, and other little knick knacks ~$70. Time spent, too much! If I were being payed minimum wage I'd probably spent $300 in labor. <br /> Of course this is a lesson in understanding outboards so I'm more than happy to do it. Conclusion, it was worth it from a personal achievement point and an economical point. I have a greater appreciation for my motor as cheap as she may be worth. Man does she run smooth, and compression is high high!! Did I mention for some reason she runs cool now also. Before I even scored the pistons she was running really hot. I noticed that the old piston rings had very little springyness to the cylinder walls, maybe they were worn out causing alot of blowby. The mystery of outboard motors

 

[Grant S]

Re: How bad is it DOC?? PIC

Thanks for keeping posting, it's been like following a mini series. It seems like you have found a good mechanic , in the end its the hands on stuff that gets the result (or not).<br /><br />Happy boating!

 

[jafa]

Re: How bad is it DOC?? PIC

Boatster, I've looked at that oil switch and my imprsssion is that it needs "some" crud on the filter to work. If the filter is perfectly clear then air will pass through the mesh and it will never create a vacume unless the oil tank is not vented , which mine is ? I wonder if your oil vent is\was blocked and as you say its drawing air from a bad connector.

 

[boatster]

Re: How bad is it DOC?? PIC

Rockhopper, I didn't know there was a vent on the oil tank. I'm going to see if its clogged or not. That could have easily been the problem. But also the two oil lines (1 from the tank to the sensor, 1 from the sensor to the pump) definitely need to be replaced. About that filter screen I think regardless the vacuum created in the line should be enough to pull the switch down. It has to be really sensitive enough that a slight vacuum will trigger the alarm I guess. I'm going to have to tweak it so it doesn't give false alarms though.<br /><br />Wouldn't the vent be on the top of the tank? Therefore the oil line connecting from the sensor to the tank should always be immersed in the oil at the bottom of the tank. The reason I had to open the top was there could have been a vacuum at the top of the tank caused by the oil consumption and it was stronger than the pull of the pump and thus it went dry or started sucking air from the bad line connections. Once I open the lid the vacuum is removed and the pump is now able to pull the oil again. That would be how I understand it. Thanks for your thoughts/observations.

 

[jleus]

Re: How bad is it DOC?? PIC

The vent is in the cap. A little "duck bill" like piece of rubber. All the pieces inside the cap will come out for cleaning. Mine got stopped up and the light "flickered" after a little running and some vacuum on the tank. Never came on fully. MY OPINION......ALL auto oiling systems, no matter the quality, will fail. Premix is the only sure way to go.

 

[jafa]

Re: How bad is it DOC?? PIC

I've got a small hole in the cap. I would agree that if the cap is blocked you could vacume the tank and draw air from a bad connector. Then there is no pressure differnce either side of the switch and it might not trigger. I suspect if its drawing air from the pump/switch side it will never trigger.

 

[jleus]

Re: How bad is it DOC?? PIC

The hole is the bleed to the exterior of the tank. Inside the cap is the "check valve". I was able to disassemble mine completely for cleaning.

 

[boatster]

Re: How bad is it DOC?? PIC

Thanks guys I will disassemble it and make sure it works. I think that may have been the major culprit it my situation. Funny how something so small can cause such a big meltdown on an outboard. Reminds me of a book I was reading about oil tanker ships. The whole engine of a tanker got disabled from a small venting diaphragm. The ship drifted in heavy seas for hours until they finally figured out what was wrong. I wonder what happened to that one grain ship in the Pacific Northwest recently that broke up on the rocks after losing her engines.

 

[jafa]

Re: How bad is it DOC?? PIC

In aviation circles " An incident is nine consecutive things going wrong that could have been prevented. A disaster is ten things going wrong "