Forum for air cooled diesel engines and clones

[xp190]

Hi 90
The rod bearing looks very clean, no scratches, no pits.
The pto main bearing, do you mean the one that crank shaft sits on?
On the crankcase cover side its spotless, on the case side, I haven't gotten to it yet, gotta take the flywheel off which is always a fun exercise.

I haven't honed any cylinders before, would you be able to give me some pointers?
I have a auto parts store which carries hones, but what am I looking for exactly?
I'll order up some rings, my understanding is you have to gap them correctly, I'm not familiar with this process yet either.

Thanks for all your help! I hope I get this guy running again soon.

xp

 

[90cummins]

I noticed the injection pump was still installed with cam removed.
Next time remove injection pump to avoid pressure on cam bearings.
90cummins

 

[90cummins]

The pto bearing is the sleeve bearing.
The hone will remove the carbon at the top of cylinder and remove the glaze on cylinder for proper ring breakin, lubrication and seal.
Google how to use cylinder hone very easy to do.
Very important to use hot soap& water to wash cylinder which removes metal particles then you must immediately dry and oil to prevent flash rust.
The ring gap must be checked with feeler gauge at the bottom of the cylinder where there is no wear.
Too small of a Gap will cause problems.
Again do s google search on ring gaping.
Go to ebay for hone
1/5
LISLE 23500 STONE TYPE GLAZE BREAKER 2 TO 7" RANGE CYLINDER HONE
4 ratings
$18.00

90cummins

 

[xp190]

Got it!

Thank you sir!
Almost ready to start reassembly, the Easter long weekend should help.
And you are right, I didn't remove the pump, I will do that once I'm back at it before I start reassembly.

xp

 

[BeeferMan]

Got mine all back together, and seems to run fine. A bit smoky, but hopefully that will improve as the rings seat.

For those who have one of the "quiet", i.e. full cabinet models - reassembling the engine was the quick part - putting all of that cabinet back together is what took the most time, lol. Got it all back together, only had one part leftover! I checked parts diagrams and all the pictures I took during disassembly, but couldn't identify where the heck this bracket goes?

 

[90cummins]

Got mine all back together, and seems to run fine. A bit smoky, but hopefully that will improve as the rings seat.

For those who have one of the "quiet", i.e. full cabinet models - reassembling the engine was the quick part - putting all of that cabinet back together is what took the most time, lol. Got it all back together, only had one part leftover! I checked parts diagrams and all the pictures I took during disassembly, but couldn't identify where the heck this bracket goes?

View attachment 545441View attachment 545442

That attaches to the engine cylinder near the exhaust outlet.
I would load the engine up to at least 50% load or more using a portable heater which will apply a constant load.
That will help seat the rings & verify proper operation.
After an hour or so tip the generator on it's side and remove the oil filter screen to check for wear particles.
There's always something on the screen after a rebuild such as lint, sealant or very small metal particles.
If it looks good clean and resume running at load for couple hours then drain the oil & check the filter again and refill.
I would also do a full load test checking voltage & frequency before calling it done.
I like to run them for a couple hours after a major repair to ensure it won't fail when needed.

90cummins

 

[OldRedTractors]

I've just spent a fair bit of time reviewing all 37 pages on this post before writing this...

I have a strange scenario on 1 of my two 186F generators. The newer one (Buffalo Tools 7K quiet model) has a total of ~60 hours on it. During a recent outage, after running just fine for about 20 hours, it started running rough, sounding a bit "off", like it was stuttering, then it would smooth out again. Then all of a sudden AC output died, but the engine was still running the same. I assumed the AVR had died, and when I looked at it, the tie-wraps had failed (nice quality install and it was bouncing around on the bottom of the housing. I ordered a new AVR, assuming this would take care of it. Also, at the time, it seemed there was a major exhaust leak that should be tended to, so I removed the muffler cover and found the bolts between the flex-pipe/cat and the first muffler had fallen out, and the gasket had disintegrated. As a result, exhaust had been blowing out of the loose connection, making a mess of the cabinet. I also noted that the inside of the cat was blown-out, and that whatever was originally in there was gone now, presumably into the muffler... I cleaned everything up, installed new gaskets and re-assembled the mufflers, installed the new AVR, and fired it up.

Still no power, so something other than the AVR, but now I have an engine problem also. It fires immediately, as normal, but will not come up to speed. Spits and coughs and blows an incredible amount of smoke. It will smooth out somewhat if I hold the governor back to a lower engine speed, but will not run up to operating speed.

I pulled the injector, and the spray pattern looks as expected when tested. Have not pulled the fuel pump. I pulled the mufflers back off, and removed the air cleaner in the event some inlet/exhaust obstruction was causing the problem. It again fired-up immediately, but belched smoke and back-fired out the open exhaust. Other than being a LOT louder, it behaved the same as before.

Something clearly went suddenly in the engine, but I have no idea what to look at. It sounds like a timing problem, but why all of a sudden? I have not pulled the oil filter to see if there is any suspicious metal bits there - will look at that tomorrow. Do cam bearing failures happen in this way - all of a sudden, or do they deteriorate over time? What else could cause a fuel timing/delivery problem like this? If it had major internal engine problems, I wouldn't think it would continue to fire off like it does.

Running with the open exhaust, you can see flames every time it stutters, leaving me to believe it's a timing problem. Any ideas?

 

[BeeferMan]

Any ideas?

It's my understanding that the injection timing is adjusted by the thickness of the gaskets under the injection pump, so that's not something that should change spontaneously. The timing gears are pretty rugged, so I don't expect it would jump time like an engine with a worn out timing chain might. A burnt/bent valve might produce some of your symptoms, but not the surging behavior you describe. So, in my - admittedly limited - experience with these engines, that sounds more like a fuel delivery problem that a timing issue. I would check your fuel filter and ensure that you're getting adequate flow to the injector pump.

 

[90cummins]

Remove the injection pump then remove the cam follower (lifter) the face that rides on the cam should have no significant marks on it.
Check the oil filter screen it should be clean. If there are small magnetic particles on it the small cam bearing may have failed.
90cummins

 

[OldRedTractors]

Pulled the injection pump, and the cam and follower look good - some minor wear on the follower, but nothing of concern. Cam looks perfect. See pics. I re-assembled it and fired it up with open exhaust and intake. It fired right up, and exhibited the same issues. Youtube video of it starting: Gen start - YouTube and running: Gen run - YouTube

Any ideas? If it had a carburetor, I'd turn in the main jet about 1/2 turn...