Using oil

[Bob]

Just drove 300 miles and used about 3/4 of a quart of oil. No smoke during start up or driving. I don't want to do a tear down so is there a good additive to slow the loss?
Also, there are no leaks.
1974, 400 4bbl, auto.

Bob

[Highbanked Hauler]

 What weight oil are you using ?

[PlainfieldCharger]

Small intake leak leak at the valley pan gasket sucking in oil... just a place to look that is out of the ordinary.

[Bob]

What weight oil are you using ?

Full synthetic 15-40

[Challenger340]

Is this a new Engine build ?  Old Engine ?  How many miles ?

[Bob]

Is this a new Engine build ?  Old Engine ?  How many miles ?

Original engine 82k. Had new gaskets and valve guide seals back in 02-03 but nothing done to the bottom end.

[Highbanked Hauler]

Just drove 300 miles and used about 3/4 of a quart of oil. No smoke during start up or driving. I don't want to do a tear down so is there a good additive to slow the loss?
Also, there are no leaks.
1974, 400 4bbl, auto.

Bob

     Get some straight 50 weight from Brad Penn for the summer but change it out for cold weather..

[c00nhunterjoe]

Almost a quart in 300 miles and no leaks or smoke?     it is going somewhere. I would say if there is nothing wet underneath, then pull the spark plugs and see what it looks like, if you find oil fouling evidence then the next simplist thing to do is pull yhe intake and look down the runners to see if it was a leaking valley pan. If the ports are clean, its a wore out motor.

[Bob]

Almost a quart in 300 miles and no leaks or smoke?     it is going somewhere. I would say if there is nothing wet underneath, then pull the spark plugs and see what it looks like, if you find oil fouling evidence then the next simplist thing to do is pull yhe intake and look down the runners to see if it was a leaking valley pan. If the ports are clean, its a wore out motor.

Since it would be awhile before I tear into it I believe it's just a tired motor. Probably needs rings since the last time I pulled the plugs they were fouled black.

[c00nhunterjoe]

Fuel fouled and oil fouled will look completely different on a spark plug. Could you post a closeup of the plugs? Were all 8 identical looking?

[Bob]

Fuel fouled and oil fouled will look completely different on a spark plug. Could you post a closeup of the plugs? Were all 8 identical looking?

Give me some time and I'll post them.
Thanks for you help.

Bob

[Bob]

Not the best pictures but it's the best I could do. I replaced them with original Mopar plugs. Right side is the front of the engine and go left to the rear.

[Challenger340]

Did you just recently switch the Engine over to Synthetic Oil ?

[Bob]

Did you just recently switch the Engine over to Synthetic Oil ?

Yes, I thought it would slow down wear.

[c00nhunterjoe]

My personal opinion is not to run full synthetic on a flat tappet cam. I would swap back to a good syn blend oil, bradd penn is my preference.
    What valve covers are you using? Are they baffled? Pcv?
   It looks like the further to the rear of the engine, the more fouled they become. Are there deposits on all of the plugs like the bottom left and top left ones?

[Challenger340]

Did you just recently switch the Engine over to Synthetic Oil ?

Yes, I thought it would slow down wear.

Bingo !
There is your problem.  Synthetic Oil when introduced to a higher mile older Engine with already glazed Cylinder walls is a recipe for Oil consumption.
The stuff is just plain too slippery....
and what was still sealing OK on Dino Oil, will quickly lose that remaining sealing ability on the slipperier Synthetic.

Now the bad news, IMO, I highly doubt just switching back to Dino Oil will cure the problem as the stuff seams to coat the metal ?
In my experience, damage done.
You can certainly try switching back to Dino Oil, just say'in..... you may find it doesn't work after a few hundred miles on the Synthetic.

[Bob]

My personal opinion is not to run full synthetic on a flat tappet cam. I would swap back to a good syn blend oil, bradd penn is my preference.
    What valve covers are you using? Are they baffled? Pcv?
   It looks like the further to the rear of the engine, the more fouled they become. Are there deposits on all of the plugs like the bottom left and top left ones?

Everything is stock to include the factory valve covers. You are correct about the plugs. The further back they were a little more fouled.

[Bob]

Did you just recently switch the Engine over to Synthetic Oil ?

Yes, I thought it would slow down wear.

Bingo !
There is your problem.  Synthetic Oil when introduced to a higher mile older Engine with already glazed Cylinder walls is a recipe for Oil consumption.
The stuff is just plain too slippery....
and what was still sealing OK on Dino Oil, will quickly lose that remaining sealing ability on the slipperier Synthetic.

Now the bad news, IMO, I highly doubt just switching back to Dino Oil will cure the problem as the stuff seams to coat the metal ?
In my experience, damage done.
You can certainly try switching back to Dino Oil, just say'in..... you may find it doesn't work after a few hundred miles on the Synthetic.

I probably ran 4-500 miles on that oil. I will switch back and see what happens.

Thank you.

[Bob]

Will a high detergent oil help clean it up?

[68CoronetRT]

If this is a flat tappet motor I'd be worried at this point of burning up the cam due to lack of zinc.

High detergent oil is for air compressors.

[Challenger340]

Will a high detergent oil help clean it up?

In my experience, only a re-hone of the Cylinders to get the rings biting again will clean it up ? which involves a teardown.
That said,
what have you got to lose trying anything at this point ?
* High Detergent ?
* Low Detergent ?
* Engine "restore" in a can ?
* Powdered Bon ami ? (Diesel fix to get old rings sealing again)
* whatever ?

[c00nhunterjoe]

Run the dog crap out of it, get things flexing. If nothing else, you'll have fun.

[Bob]

And here I thought I was doing a good thing for my engine.
Crap!!!!!

Thanks for your help.

Bob

[flyinlow]

A quart in 400 miles is not the end of the world.  The plugs (depending on how many miles are on them) don't look that bad. The left lower one is showing oil consumption. Worn rings will show oil smoke under hard acceleration. BB  Mopars I have worn out show oil fouling on the rear cylinders first.  If you drive 2000 miles a year and the plugs go that distance , keep driving. Check your oil every fill up.

[Bob]

Narrowed down to Bon Ami or Seafoam with an oil change.

Thoughts?

[PlainfieldCharger]

Put some 20W-50 in it with the ZDDP additive and run that before you do the other additives. Throw in some new plugs and drive it for a while and pull the plug the was fouled the most....post a pic for the board to see....

[c00nhunterjoe]

It may not even be the rings. The front plugs dont show any deposits that i can see from those pictures. I wouldnt add any detergents, its a waste IF you have kept up with regular service which it sounds like you have. Just run a good blend oil and see how it does. If it still uses oil, run a compression test and if all are good then remember loose is fast, dont worry about it until you plan on a total overhaul.

[Bob]

It may not even be the rings. The front plugs dont show any deposits that i can see from those pictures. I wouldnt add any detergents, its a waste IF you have kept up with regular service which it sounds like you have. Just run a good blend oil and see how it does. If it still uses oil, run a compression test and if all are good then remember loose is fast, dont worry about it until you plan on a total overhaul.

The plugs have been in for about 4 years and the oil gets changed at least twice year since I only run about 700 miles a year. I just purchased some good 20-40 and we will see how it goes from there without any additives.
I thought the plugs looked good also except for that one back one.
I will update the post as time goes on.


Everyone, thanks for your input.

Bob

[c00nhunterjoe]

Where did you get 20w40? You do realize that this time of year 5w40, 10w40, 15w40 are all the same viscosity right?

[Bob]

Where did you get 20w40? You do realize that this time of year 5w40, 10w40, 15w40 are all the same viscosity right?

Hind sight being 20-20 I thought the same thing sitting here. I guess the all around should have been 15-40.

[c00nhunterjoe]

10w40 is typically cheaper and more readily available, and if you ever did drive in cold temps, it would be better as well.

[Bob]

Changed the oil and the oil pressure came back up to normal. Miles will tell now.