Another oil consumption threaad

[alke46]

Sorry, I know we all get tired of hearing about high oil consumption but I just need to see if my own diagnosis is correct.

My bike had sat for 4 years due to other needs and just a couple of months ago I finally got it ready to ride. Valves checked, carbs dipped, synched as so on. I have just this month alone put on a little over 1,000 miles on it and while it does run pretty well, it is using oil at the alarming rate of 1qt. per 350 miles.

No smoking on start up. No leaks on the garage floor, no apparent leaking gaskets that I can see anyway. Last time I had my son ride it while I followed, it did not show any smoking going down the road. WTF?????

I am guessing that it needs a tear down with cylinder honing and new rings as well as valve train refreshing, i.e. new guides and stem seals.

Am I right or am I just missing something? Thanks for all your good insights. I will be checking back for your answers every 3-4 hours today.

Thanks,

Larry

[Brendan W]

What do the plugs look like ?
With my optimistic hat on I would be hoping it's stuck rings after the lay up and try one of those ring unsticker things in the fuel.
How much is coming out the breather ?

[alke46]

What do the plugs look like ?
With my optimistic hat on I would be hoping it's stuck rings after the lay up and try one of those ring unsticker things in the fuel.
How much is coming out the breather ?

#1 and #4 look perfectly tan on the electrode. #2 is only slightly darker and #3 is my problem carb. Cannot get it to lean out properly. It runs rich and has been running irregular. One tank of gas and it seems ok, then the next tankful it runs just like the fuel level is too low and needs to be switched over to reserve. It acts like I did not get it clean enough. Will have to pull the carbs off to check that.

I am using Marvel Mystery Oil in the crankcase at a 30% mix with the regular diesel 15w40 oil hoping to break loose a stuck ring but no luck yet. Maybe I'll try another additive instead of the MMO.

Don't know how much is coming out the breather. Will have to check that out.

Thanks,

Larry

[alke46]

Checked the compression today and got the following numbers: #1) 140 #2) 135 #3) 120 #4) 140. The spark plugs also indicate 1,2,and 4 a nice tan color. #3 is very dark, i.e. rich burning. Could this be a tight valve shim?

Thanks,

Larry

[eil]

Running rich is typically a carb problem. Valves clearance shouldn't have anything to do with it, although if you're not sure what your clearances are, you should do them anyway.

It's possible that it's not running rich and that you have a bad valve seal in #3, causing oil to get into the cylinder. Although you usually see that by lots of smoke at start-up, which you've mentioned you don't have.

Maybe check the float height in carb #3? (And compare it with the others?)

[alke46]

Running rich is typically a carb problem. Valves clearance shouldn't have anything to do with it, although if you're not sure what your clearances are, you should do them anyway.

It's possible that it's not running rich and that you have a bad valve seal in #3, causing oil to get into the cylinder. Although you usually see that by lots of smoke at start-up, which you've mentioned you don't have.

Maybe check the float height in carb #3? (And compare it with the others?)

Interesting observation, thanks for that. I agree the rich condition should point to carburetion and the valve clearances were good when I last checked them right before I started riding it again.

The idea that a bad valve stem seal could be causing a problem is justified. Before I changed over to a stock exhaust system there was noticeable smoke at start up and the former mufflers were extremely sooty. However, that all changed once I replaced the 2 sizes over main jets and put it back to stock. That is a good sign that a seal might be bad and something else to check once everything else is eliminated.

I will be going through the examination process within the next few days to check on such things as float heights. Are they likely to changed after carb reassembly? I had them all set at the correct heights before putting the carbs back together and on the bike.

Would a bad valve stem seal cause the compression difference? I don't know. Will wait for an answer.

Thanks,

Larry

[Brendan W]

Would a bad valve stem seal cause the compression difference?

No. Next time the headers or carbs are off you could put on your miners helmet, take a canary with you and go exploring. Leaking stem seals appear as oily deposits on the neck of the valves dribbling down from above.

[duaneage]

I had a leaky head gasket that made number 3 low. It does happen.

[alke46]

What sort of sign did that leaky gasket give you? Am I correct in assuming that you could hear the leak? Was it on the exhaust side?

[duaneage]

It ran ok but when I pulled it apart I noticed that the gasket was damaged. Water had gotten in through a head stud and it rusted the gasket. The metal gasket rusted and it leaked out past. My 1000 probably lived outside for a while, the left side showed signs of water sitting in places.

[duaneage]

I drove my 1000G to eagle Nebraska last summer. Love that 80mph speed limit

[alke46]

I drove my 1000G to Eagle Nebraska last summer. Love that 80mph speed limit

You must be a dirt track race fan eh? Not much more to see or do in Eagle. I ride past that track probably once a month.