motor using oil

[rockyman]

i have a 1978 inline 6cly 250 chevy motor 165 outdrive merc. almost 600 hrs on motor . is it normal for these motors to burn a little oil ?

 

[Don S]

Re: motor using oil

Normal no, but a lot of things can happen in 30 years.
Have you done a compression test? How does it run? Are the plugs oil fouled, do you have leaks, does it smoke?

 

[rockyman]

Re: motor using oil

no compression check at this time , no smoke , runs like a scaulded dog,plugs are fine.

 

[ziggy]

Re: motor using oil

is it normal for these motors to burn a little oil

Normal no

i guess i'm under the impression that all 4-stroke engines use a little oil. could be i'm dreaming that that is a fact. i felt i've read enough times about 4 strokes useing small amounts of oil, i just quit worrieing about it.. maybe i'm wrong and should be worried too and don't know any better. i'm not a tech.....
as for the 30 year old engine... mine is too, and i suspect i use a little more oil than what i'd consider normal... especially if i give it a longer wot run.... i don't smoke, least not that i can see and my plugs don't look overly fouled.... my compression is on the outside of spec.
guess the way i see it.. i'll just add some oil every now and then. ya should check it often anyways.... when i'll get worried is when my compression goes out of spec. or it starts to drink heavily......

fwiw... i had one of the first 4 stroke pwc when released by yamaha. (probably only thing similar to a L6 was that it was a 4 stroke engine) it drank way more oil than my L6 has ever drank.... there was nothing wrong with it that i was aware of, it just liked to drink more than i thought it should have.... i got that new with 0.0 hrs... sold at 235... never had one problem with the engine...


might as well check yer compression now... while it's running like a scaulded dog... ... then when somethings up. ya'll have something to compare to....

 

[Don S]

Re: motor using oil

is it normal for these motors to burn a little oil

I ASSUMED he meant an abnormal amount, But then again, that's always what happens when I assume something. And what is a "Little bit" and over how long.

 

[JustJason]

Re: motor using oil

its normal for 4 strokes, especially in boats to burn a little as people have said. But.... how much do you think your burning? And more importantly, what brand and weight oil are you using?

 

[mthieme]

Re: motor using oil

...and how hard do you run it.

 

[rockyman]

Re: motor using oil

well don you got me there because i really cant explain it with out knowing how many hrs per use and i havent been keeping up with that but i have been checking it before each outing.guess i should put this on the back burner for now untill i get all the facts together .thanks for your input

 

[Bondo]

Re: motor using oil

Ayuh,...

How many added quarts, per oil change interval will narrow it down quite abit...

But then again, that's always what happens when I assume something.

A Wise old Wizard once told me to Never Assume,... Anything, when giving advice on a forum.....

 

[ziggy]

Re: motor using oil

How many added quarts, per oil change interval will narrow it down quite abit...

i'll add a question. how much would be normal?

i've not kept track of it in that manner..... nor have i kept track of it at all other than in my mind for that matter. guess i'll have to do better record keeping about this.. best i can recollect i add about 6oz. for somewhere between 10 and 15 hrs. i do 1 oil change in mid summer. rough guess w/o a hour meter is 100hrs a summer. so 50 hrs per oil change. so 30 oz on the outside per 50 hours..... i consider my engine somewhat tired. probably not runs like a scalded dog though. i'd say mine performs satisfactorily and i reach wot on the high side with ease under normal load conditions... oh, forgot, gotta include the pushrod cover gasket that leaks, that i gotta fix... so there goes some of it... i suspect i use slightly more than i should, but not enough to be overly concerned about it, yet.....

 

[turborich]

Re: motor using oil

Not sure about boats or this particular engine. However I do know that some engines just burn oil & it's considered completely normal while other engines do not burn any oil & if they did it would be considered to be an issue.

In a car I could easily see an older engine using a quart per 3,000 miles.

I would think that a 30 year old engine would burn some oil as tolerances were not as tight back then as they are now, just not sure about how much. If the plugs are not fouled & the engine runs good then I wouldn't worry about it.

 

[ne7800]

Re: motor using oil

i have this motor in my 1970 Chevy C-10 and i burn/leak almost a quart in 700-1000 miles was much more till i replaced the side cover gaskets

 

[chiefalen]

Re: motor using oil

I would if it were my boat perform a compression check.

Very simple, half hour tops your done.

Does 2 things one you get to check your plugs,2 you find out what if anything is wrong with the valves and lifters.

But the big question how many quarts say a half quart to a quart all summer no big deal.

If your putting a quart in every time you go out than it's a big deal.

Are you leaking it? Into the bilge?

Than it's the pan, timing cover,etc.

Sheeet Don already posted to do the compression check, i re-read the entire thread.

I didn't have my first cup of coffee yet. Sorry.

 

[rockyman]

Re: motor using oil

as a mater of fact i do get some oil in my bilge and i have been wandering how it was gettin there.

 

[chiefalen]

Re: motor using oil

Yea wonder no more while it's running take a mirror and look at the oil pan and lip of the timing cover.

Or put newspaper under the motor after you get the bilge dry.

Big question why didn't post that also your dripping oil into the bilge.

Just gonna get worse. Till one day your gonna run it dry the sump and than your posting how to install a new motor.

We will help you with that also.

 

[rockyman]

Re: motor using oil

lol i hear ya man i know a little about changing motors not as much as you guys though. if in fact thats where the oil is coming from is that just a gasket replacement.maybe a crank or two on the bolts to tighten them up a bit .

 

[ziggy]

Re: motor using oil

keep in mind that oil leaks run doowhill when looking for it...
my 1st L6 had a leak. some creaton had the back of the valve cover gasket all folded in + sillycone.... it was a mess. least it was easy to find.... go look for it... like i said, mines snibblin at a pushrod cover gasket.... so they can leak anywhere... also, yer trim might have 30w in it. motor oil... so that would also be suspect for motor oil in the bilge... of corse that won't effect engine oil consumption...

 

[abj87]

Re: motor using oil

Valve cover and side cover would be the first place i look on long motors they tend to warp if someone over tightens them and distorts the cover. i had a hell of a time to get the cover on my amc strait 6 to stop leaking. A little oil consumption is normal on older motors over time the rings loose tension and allow a little more oil past into the combustion chamber expectialy at high rpms. If everything else is fine whats the big deal in adding a little oil every now and then.

 

[rockyman]

Re: motor using oil

hey ziggy its funny you should mention that about the bilge because i had the bellows changed and also a yoke seal replaced would there be any connection there

 

[ziggy]

Re: motor using oil

the yoke seal keeps gear lub in yer drive the way i get it. so if that seal leaks, ya get drive lub in the bellows, not engine oil. a poor job of doing the deed would be replace the seal reinstalling on a bad yoke. ie rust at the seal location on the yoke boss where the seal rides at. this would likely leak drive lub into the bellows, but not engine oil...