Engine Oil/Noise Diagnosis Questions - low oil and tapping noise during extended ride

[bananacycle]

I started out a ride cross country, from PA to CA on my 1982 gs850 gl, with an oil change, which took a recommended 4 (3.8) quarts. I noticed nothing for first 1100 miles, when I started to hear a tapping from engine, I pulled over immediately and saw that there was no oil in viewport. I was about 40 miles from nearest autoparts store and rode it there gingerly. It took 3 quarts to get it back to full. From that point, the tapping noise fluctuated its intensity at certain rpms over next 24 hrs. It settled into loss of power and a loud tapping across all rpms and hasn't changed since. I rode about 2000 miles more on that ride, oil level didn't drop at all in rest of ride. I know that I was doing damage and taking risks, but I made it across and now need to start assessing the damage. I am going to start pulling it apart tomorrow. I will update as I go along, but was wondering if people had any initial experience with the massive drop in oil during that first 1100 miles after an oil change (it was warm and had run it before final check on oil levels at time of the change). I saw no evidence of an external oil leak, or significant levels of smoke.

Other then the possible damage to my bike it was an amazing ride!

(first post - but lurked since last summer when I bought my first bike and used tutorial to rebuild carbs and defunk the gas tank and fuel lines.)

 

[tom203]

Yes, it sounds like an amazing ride! Were you headed home, or leaving home?
After discovering the need for oil, did you notice any oil on bike's exterior? was oil cap on tight?

 

[bananacycle]

Was headed home, moved from east to west coast and was transporting bike and having some fun while I was at it. At the time, I did not really noticing any extra oil on exterior, and leaks as I pulled to stop, and the oil cap was on tight. Now that I am pulling it apart there is a little bit of extra oily grim on valve cover.

I got the valve cover off today so I could really take a look at it and I discovered at least one source of the noise. The forward right camshaft bearing cap was loose. 3 bolts had self loosened and one bolt was broken off. After taking it off, I saw that the bearings and race are all wrecked. I am guessing that I will need to order replacement before I can to a good valve adjustment.





Question: Should I replace camshaft and see how it runs or should I look deeper while it is open and see if there is damage to the pistons?

 

[Guest]

throw up some pictures of the camshaft and the race and head, as they say, 1000 words

 

[Cipher]

Why did you drive a bike without oil? Beyond short sighted.

 

[dorkburger]

Make sure the broken bolt is accounted for.

 

[bananacycle]

Azz - I attached some pictures to previous posts cause I don't know how to add more then one per post... oh well, e-tech not my thing.
3rd pic.


DB - the broken bolt was still in head just resting there so there is no missing parts floating around gear engine. thank goodness.

 

[Fjbj40]

That's what you call dead!

time to look for new head or engine

 

[bwringer]

Poke around for a good used 80-83 GS850 engine and plop that in.

At the very least you'll need a good complete cylinder head, but overall I think you might be money and time ahead just scaring up an engine. If you're in SoCal, surely there's one out there somewhere close by.

Make sure you get the driveshaft as well if you end up with a 1980 engine -- it's very slightly different. Other than that, it's a straight bolt-in. The clutch and valve covers are different between the 80-81 models and 82-83, but that doesn't make much difference other than when you're ordering gaskets.

 

[Guest]

Amazing that you rode another 2000 miles with that type of damage, I can only imagine the noise that was happening, not sure how you kept riding with all that going on. That top end is as dead as they go and likely you've got piston damage or maybe even crankshaft bearing issues?? you're lucky nothing bad happened to you.

 

[Mechanically Geeky]

I feel your pain, as I had the exact same situation except instead of lack of oil I had lack of oil pressure. I'll post a picture of the carnage.

I ended up buying a whole engine from a salvage shop and swapping out the top end. In your case, you may want to replace the whole engine as the bottom end may be questionable? Just my two cents.

 

[bobgroger]

That is not fixable. These are tough motors, but can't survive no oil. You might be better off to consider total replacement. An 1100G motor drops right in

 

[bananacycle]

I guess I am between replacing just the head and cams or the entire engine. Below is a photo of the tops of the pistons, what do you all think? '

what you cant see is the sides of the pistons look good, no metal on metal looking damage. Is that a sign that the crankcase and contents may have been left in good condition as well. (no metal in oil when I changed it).

 

[Guest]

The base has to be pulled off anyways to replace the base gasket so pull it off and have a good look at the pistons. If the sleeves look ok at least that's a good sign. You can't tell if the crank is ok without taking it out, meaning splitting the whole engine. Your top end gasket kit is going to cost $200 anyways, might want to start looking for an engine.

 

[Fjbj40]

Piston head tells nothing of cylinder wall damage.

 

[bananacycle]

Well it doesn't look like there is any wear on the piston walls. I am looking into replacing the heads. I have someone with a 79 850 head, is it compatible with the 82 850 carbs and engine?

 

[Big T]

No, 79 is a one year only bike