Finally bought a MEP-831a

[AfghanVeteran2010]

Thanks

Ill clean piston with carb cleaner and a scotch brite pad.
I order
--Yanmar L70 L70AE L70EE Replacement Piston Ring Set 714870-22500
--Yanmar L70 L70AE Complete Repair Gasket Set
--Brush Research FLEX-HONE Cylinder Hone, GB Series, Silicon Carbide Abrasive, 3-1/4" (83 mm) Diameter, 240 Grit Size
--OEMTOOLS 27039 Piston Ring Compressor
--Lisle 33500 Piston Ring Installer

 

[AfghanVeteran2010]

I cleaned the piston, do they make gloves that hold up to carb cleaner? I realize that I need to clean under 1st ring, I ran out of cleaner. I do see light vertical scoring on piston sides. Hone should be here tomorrow at some point, the rest will arrive later during the week.

 

[AfghanVeteran2010]

I'm trying to understand what was causing the issue while engine was running at load. Right now I'm assuming it was the bore having scuffing marks and being glazed causing the rings not able to form a complete seal.

I received the bore hone, going to clean the cylinder out and get it perfectly clean. Don't want to hone it with garbage in it. Also going to break down cylinder head and clean it out as well as check valve seal surfaces.

Thanks

 

[Another Ahab]

I received the bore hone, going to clean the cylinder out and get it perfectly clean. Don't want to hone it with garbage in it. Also going to break down cylinder head and clean it out as well as check valve seal surfaces.

Is there a preferred/ recommended way to do that cleaning (other than the "regular suspects")?

 

[AfghanVeteran2010]

Im no mechanic, but I plan to wet a towel in carb cleaner and wipe cylinder

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[AfghanVeteran2010]

Cleaner now, might need another cleaning after looking at picture. I ended up using a screw driver in drill having the handle warped in a towel, soaked the first half in carb cleaner. I did the after using a towel by hand kinda got tried of hitting my hand on studs. I did notice some really good scratches in top of cylinder bore after removing the build up, I don't think the towel could of cased that.

 

[AfghanVeteran2010]

I pulled valves off of cylinder head, I noticed that the intake valve has a crap ton of carbon/soot in it. ​Edit: Probably unburned fuel from low compression.
Intake



Exhaust

 

[rustystud]

Your piston looks fine. Yes you have a bit of carbon build-up and that is due to the unburned fuel. Your probably correct about the low compression causing the build-up. The cylinder bore is a bit scratched up. Maybe some dirt got in there when it was running and that helped the rings go also. You need to be extra careful on diesel engine air filters. Replace them on a regular basis, and clean the housing each time you do. The ball hone should clean-up that bore OK. Post some pictures after you hone the bore.

 

[AfghanVeteran2010]

What do you define as regular basis?

I've been watch videos on how to use ball hone, ill hone it tommrow if I can.

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[AfghanVeteran2010]

Today I checked valve surface the exhaust valve surface is pitted, can this be lapped out with grinding compund, or do I need new valve? I have not honed cylinder yet I decided that I need to remove the crankshaft and fly wheel, I don't want to damage it or get contaminated liquids on it. Mainly oil form honing and water that is use to clean cylinder out.

 

[Guyfang]

]What do you define as regular basis?[/COLOR]

I've been watch videos on how to use ball hone, ill hone it tommrow if I can.

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Have you forgotten about PMCS? Service schedule? The LO for your gen set is in the manual!!

 

[AfghanVeteran2010]

I was just wondering if Rusty meant that filters should be changed sooner than what TM/Manual specified.

 

[Guyfang]

In the TM, it states that if the conditions warrant it, then the filters should be changed more often. Here in germany its not a problem. At White Sands New Mexico, different deal. The last time I was in Odessa, I would have told you to change the filters!! It looked like a tornado was about to drop in. The air filter can be cleaned with compressed air. That's one filter I always kept a close eye on. At some point in time it's a throw away. With the fuel filters, its all about what comes out of the filter drain. If no water or dirt comes out, then change IAW the LO. If you look into the fuel tank with a flashlight and see dirt, water and other trash, its a good idea to keep a closer looks at that petcock. What comes out. And the oil filter is a cheapie. They don't cost all that much, and if you run good oil in the engine, well, its cheaper to change filters then oil. But that's my thoughts on it. When I spent months in the desert in El Paso, we changed filters once a month.

 

[AfghanVeteran2010]

Today I checked valve surface the exhaust valve surface is pitted, can this be lapped out with grinding compund, or do I need new valve? I have not honed cylinder yet I decided that I need to remove the crankshaft and fly wheel, I don't want to damage it or get contaminated liquids on it. Mainly oil form honing and water that is use to clean cylinder out.

View attachment 692103

I asked my brother about removing the pitting by using valve grinding compound. He said it will probably mess up the seal, I'm going to order new valves for it. I took a closer look at crankshaft and fly wheel, I don't think ill be able to remove it with out the flywheel locking tool. I'm just going to have to cover the baring surfaces with some thing, I plan on cleaning out the crank case with carb cleaner after the cylinder is honed and washed with warm water. As well as oiling the cylinder when I'm done. Is carb cleaner too strong, ill remove plastic dipsticks when I do this?


Thanks for explanation Guyfang.

 

[AfghanVeteran2010]

I managed to find a (HANDEL, FLYWHEEL LOCKING) on Ebay, it seems to be a hard tool to acquire. (NSN 5120-01-415-8266) (Yanmar 114250-25101)

I'm going to wait till I receive this tool to progress on the engine.


Thanks

 

[Another Ahab]

I managed to find a (HANDEL, FLYWHEEL LOCKING) on Ebay, it seems to be a hard tool to acquire. (NSN 5120-01-415-8266) (Yanmar 114250-25101)

When that comes in, can you post a pic of it here for us, please?

 

[AfghanVeteran2010]

When that comes in, can you post a pic of it here for us, please?

Here the one on listing

 

[Another Ahab]

When that comes in, can you post a pic of it here for us, please?

Here the one on listing

View attachment 692216

You really deliver, AfghanVeteran2010!

Thanks a million.

 

[AfghanVeteran2010]

I discovered some pitting on engine block, while cleaning surface. Can this cause issues? I have been using carb cleaner and a scotch bright pads. Can of carb cleaner only warns against paint and plastic. I think it was caused by all the crap that was on it before i cleaned it.

 

[DieselAddict]

The pitting in the block isn't going to cause the problem.

It will be best to buy new valves and dress the valve seats so make sure you get a good seal. A light lapping is OK but you aren't trying to get everything perfectly parallel. You want a thinner contact area to start with so the force the valve closing onto the seat causes them to wear into each other.