MR1 engine failure analysis

[Truck4dog]

At the end of last season (for me) I had a catastrophic engine failure. I noticed a bottom end knock and chose (poorly) to push both engines back to the ramp. I'm still not 100% sure of the exact problem. The final failure was when the #3 rod came through the side of the block. During the long block installation inspection of the oil pump revealed some gouging and a rebuild kit was ordered and the oil reservoir disassembled and cleaned. The reservoir was full of failed engine glitter and at the bottom of it all is the screen that prevents the metal flakes to be circulated.

My port screen had a nice little hole in it. In my attempt to drain all of the oil, I most likely pushed the suction tube into and through the screen opening the door to large particle contamination of my engine oil and possibly contributing to my engines early demise. I'll check the starboard engine and post what is found.

Please excuse my dirty bench.

 

[Speedling]

Goodness... i need to be careful when i suck it dry! I use a flexible hose to go down. Did you use something ridgid?

 

[Jack Long]

How many hours on the motors?

 

[Scottintexas]

If you still have the engine out it may be good to take a look at your exhaust passages and see if they are blocked at all,

 

[buckbuck]

Thanks for the info. Please send pictures of anything else you come across.

 

[Truck4dog]

Here is a pic of the outer oil pump housing and the debris in the gear reduction unit.

How many hours on the motors?

488 and 490. There were probably multiple reasons for that one to fail, I'm posting things as I find them.

 

[Liveto99]

Looks like the crap left in the boat hull from when it was made. I thought the motors were made in Japan, and had better workmanship.I thought they Harry Carry when they make a mistake at work.
Maybe I watched to much Sat. Night Live in the 70’s

 

[Beachbummer]

I wouldn't be so sure that's left behind from when the engine was put together...with a blown rod those could be metal parts from the impact, or bearing that was destroyed, or who knows what else was destroyed when it failed.

 

[Truck4dog]

Looks like the crap left in the boat hull from when it was made. I thought the motors were made in Japan, and had better workmanship.I thought they Harry Carry when they make a mistake at work.
Maybe I watched to much Sat. Night Live in the 70’s

Sorry I my wording was bad. The gear reduction system and oiler are at the back of the engine. All that was inside the engine oiling system and on the pick up screens. Here is another pic of another screen. The rod bearing was chewed up and the rod came through the block. All of the shaving are from the inside of the engine.

 

[Scottintexas]

Thank you for the oil reservoir pictures,

I'm wondering and can't make out from the first and second pictures,

When we put the suction tube in we hit bottom and if we move the tube we can sometimes get it to another level another 1/2" further down,

I'm wondering if we have all poked holes in our screens or where that 2nd level is in your photo?

@buckbuck @Bruce

 

[Truck4dog]

Thank you for the oil reservoir pictures,

I'm wondering and can't make out from the first and second pictures,

When we put the suction tube in we hit bottom and if we move the tube we can sometimes get it to another level another 1/2" further down,

I'm wondering if we have all poked holes in our screens or where that 2nd level is in your photo?

@buckbuck @Bruce

This pic is of the oil reservoir without the top cover. There is a metal plate about an inch or so above the bottom of the reservoir with a hole directly above the screen on the bottom. I think it is when I went a little further down that I poked through. I was using a semi rigid plastic tube to suck the oil out.

I'll take more pics when I check the other engine and post them for everyone.

 

[Jgorm]

Major bummer! The screen at the bottom of the oil tank is pretty heavy duty. I doubt you could puncture it with rigid poly tubing if you tried. Was it possible that it was low on oil?

 

[Truck4dog]

Major bummer! The screen at the bottom of the oil tank is pretty heavy duty. I doubt you could puncture it with rigid poly tubing if you tried. Was it possible that it was low on oil?

When I say I punctured the screen the reality is that it was caved in and pulled out from the edge. The screen is sandwiched between two thin pieces of metal.

 

[buckbuck]

@Truck4dog Many, if not most of us, with MR-1 engines have learned to prod around and find that slightly deeper hole when we suck out the oil. If we are doing this wrong we need to get the word out to everyone. Are you feeling certain that this prodding caused the screen to fail?

 

[Truck4dog]

@Truck4dog Many, if not most of us, with MR-1 engines have learned to prod around and find that slightly deeper hole when we suck out the oil. If we are doing this wrong we need to get the word out to everyone. Are you feeling certain that this prodding caused the screen to fail?

I'm going to take the other tank apart and check it out. I'll post pics of the disassembly and share what I find.

 

[Scottintexas]

any update?

 

[Truck4dog]

Not yet. Got busy with another project and the boat is pushed back until next weekend. I'll keep everyone posted.

 

[biglar155]

Looking forward to the findings on the other side.

 

[BlkGS]

Is this screen something that can be inspected without a ton of disassembly?

 

[gthh]

I am very curious what could lead to a catastrophic engine failure.
but....
Last I checked I only put clean oil in my reservoir and doubt (my opinion) that a hole in screen as shown would cause a failure as described form recirculated oil from a 400+ hr engine. So, I would be very interested to know more (I have a (two) vested interest in this topic).