Top end starved of oil.

Moto Militant

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Can you guys take a look at the attached picture of my rocker arms and camshaft.

I'm doing a top end overhaul and hoping I don't have to split the case. I didn't find any large particles in the engine or oil filter but the drain plugs caught a lot of the metal which formed into a sludge.

My question is can I get away with a flush on the crankcase?

Any advise is very appreciated.
 

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are you sure your not getting oil up top? look in the manual on what tolerances you oil pump need to be. I started with a shattered piston. I went thru a case of brake cleen cleaning out every passage. I get lots of oil spray up top.
 
Definite lack of oil up there causing the rockers to burn away. What caused it?..........Dunno. PO could have done a number of things...........Ran low on oil..................pump failed at one time and wasn't picked up before damage was done...........pump could be damaged now and is still the problem. With the rockers as damaged as they are the valve settings would be very difficult to get right, this could cause your timing to be out
 
I would recommend you split the cases and clean oil passages and inspect the crank replace the seals. Chances are the oil pump failed causing the damage to the cam and rockers. Scored piston also lack of oil also. Do it right the first time.
 
Well boys y'all are going to get a kick out of this!

I plugged the tach hole in the side cover with one of those cute little aluminum plugs. I had no idea the oil pump was part of the side cover. I thought the gear I was looking at only drove the tach. I removed it! I'm an idiot! There I said it..

Now that you know that do you really think I have any business splitting the crankcase lol.

So, with that said I know I only put about 200 miles on her after I pulled her heart from her chest and one of the rocker arms broke. Should the case still be split?
 
I'd do a Complete overhaul. Otherwise your going to be chasing your tail. Fix one thing and something else breaks soon after....
 
Nothing wrong with honesty, i makes me think you are a good candidate to use the resources of this site for a rebuild.

I have limited my advice on Tach removal due to the advice being ignored to often. The Tack is the only way to reliably ensure your oil pump is working. If the Tack stops, it more than likely is the cable, but to keep riding when it has, is inviting the same out come as yours. An oil gauge can help, but oil pressure is minimum, especially when the oil is hot.

Splitting the cases and flushing the oil galleries is easy enough, give you a chance to check the condition of the crank and if it is sound it's just a case of reassembly and top end rebuild. many have done it through here, and there are a coupe of good threads with pics that are available.
 
well one thing is for sure those rockers are shot ! That damage has been caused over a considerable number of miles /years .
You should definitely replace the rockers or as Skull says you'll find it next to impossible to set the tiny clearances accurately .

Splitting the cases is easy to say from behind the keyboard but even for a seasoned engine builder ,...its a lot of work and can be very expensive on parts .

For a novice I personally wouldn't recommend it. Many a bike has been abandoned because the owner was unable to afford the replacement parts or found the work too challenging. Ebay is littered with abandoned xs650 projects.

Others will doubtless disagree with me but If it were me in your position ....I would do a thorough decoke and clean of the engine replace the rockers and any other parts that are unservicable.
Buy a decoke gasket and oil seal set and refit the engine. Renew the oil pump .Ditto the rings ,hand hone the bores , etc
Check and set the timing, cam chain tension , valves , mixture etc and run it.
You can remove the valve covers whilst the engine is running and check the oil flow to the head.
Keep a watchful eye on everything and at 100 miles or so when you retorque the head you can remove the valve covers and check the oil flow again.

If it doesn't work then I'd recommend you buy a used complete engine/gearbox that you've seen running and drop that in. it will be a lot cheaper and less stressful than trying to rennovate one
 
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Wow...................200 miles with no oil circulating:yikes:. It just shows how robust these engines are. An engine with journal type bearings would have failed much,much sooner. The engine must have been making some loud mechanical noises!
Moto Militant earns my respect, for coming on here and being honest, that he removed the oil pump drive. Others might have tried to cover up their deed by saying the pump failed or there was an oil blockage.
 
oops .....thank you RG......I'd completely forgotten about the bit where the engine ran without oil for 200 miles :D

Goodness knows what the rest of the gearbox is like .
Guess the best option is to fit a used engine so you can still use the bike and maybe rebuild the toasted one when you have the time and resources and can take your time on it over the Winter maybe
 
All the signs were there but I couldn't figure it out until after the failure. The rocker arms were burning up and smoke was blowing out the crankcase vent. I was trying to determine what was causing it thru another thread unsuccessfully. I read that it is common to see a little smoke but I thought it was excessive. I thought maybe this is blow by so I performed compression checks and a leak down test that confirmed the bores were fine.

And yes the rocker arms were making racket too so I researched it and found they are a little noisy. And no surprise that I couldn't get the valves to stay adjusted as they were being grinded away.

retiredgentleman,

Trust me, my first thought was to BS y'all but I need help and that is why I am here.
 
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