excessive oil useage
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,118
From: Crossville TN
Do you have a working PCV system on the car? Does the valve cover with the PCV valve installed have an oil baffle below the valve so that splash oil does not get sucked into the intake??? This is a common problem for many aftermarket valve covers (cheaper to make without the baffles).
Burning Brakes
Joined: Jan 2017
Posts: 1,096
Likes: 213
From: The Buckle of the Bible Belt. Joplin Mo
Valve stem seals, if they are bad will allow the oil to drop onto the piston. This will cause excssive smoke on start up and then dissipate. If you are not seeing this, keep looking for the cause.
Have seen a similar problem on a C-1 that was caused by a poorly installed intake. The manifold did not fit correctly and oil was being sucked into the combustion chamber. Lots of oil loss, but no leaks and very little smoke. Not sure if this is the case with your C-3, but thought I would share.
Have seen a similar problem on a C-1 that was caused by a poorly installed intake. The manifold did not fit correctly and oil was being sucked into the combustion chamber. Lots of oil loss, but no leaks and very little smoke. Not sure if this is the case with your C-3, but thought I would share.
Safety Car
Joined: Apr 2006
Posts: 4,057
Likes: 421
From: BC
Do you have a working PCV system on the car? Does the valve cover with the PCV valve installed have an oil baffle below the valve so that splash oil does not get sucked into the intake??? This is a common problem for many aftermarket valve covers (cheaper to make without the baffles).
I used aftermarket valve covers and even though they had baffles, they didn't work properly. I went from a quart every 600 miles to 6000 miles after replacing them. Below is an easy and inexpensive check that I use. Get one of those cheap glass fuel filters and install it in the pcv line at the carb base. Just pull the line off the carb and install the filter between the line and carburator. There are 60 tablespoons to a quart so if you have a tablespoon in there after 10 miles that would equal a quart every 600 miles just through the PCV. You can unscrew the filter to clean it for future use and it's only about 5 bucks. Kind of a dangerous fuel filter but works great for this. Then you know for sure if, and how much oil you are sucking in through the PCV before looking at valve seals or whatever.
Last edited by CanadaGrant; Oct 3, 2019 at 11:45 PM.
Thread Starter
Cruising
Joined: Aug 2013
Posts: 14
Likes: 0
bigdaddy33
3 qts in 280 miles at 70 mph on hwy, With 3.70 gears at 70 mph I'm turning 3,200 rpm. Using Mobil 1 10w - 40. I tried other premimum oils and the results are the same.
Before changing the Valve Stem Seals I plan to check the spark plugs, PCV Valve/hose, run compression test and leak-down. I do not want to replace the Valve Seals
and end-up with the same problem. I have a small oil leak coming from the rear main seal area that appears only on the garage floor but not on the underside of the vette.
Before changing the Valve Stem Seals I plan to check the spark plugs, PCV Valve/hose, run compression test and leak-down. I do not want to replace the Valve Seals
and end-up with the same problem. I have a small oil leak coming from the rear main seal area that appears only on the garage floor but not on the underside of the vette.
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Le Mans Master
Joined: Sep 2001
Posts: 7,739
Likes: 630
From: Unreconstructed, South Carolina
Valve stem seals, if they are bad will allow the oil to drop onto the piston. This will cause excssive smoke on start up and then dissipate. If you are not seeing this, keep looking for the cause.
Have seen a similar problem on a C-1 that was caused by a poorly installed intake. The manifold did not fit correctly and oil was being sucked into the combustion chamber. Lots of oil loss, but no leaks and very little smoke. Not sure if this is the case with your C-3, but thought I would share.
Have seen a similar problem on a C-1 that was caused by a poorly installed intake. The manifold did not fit correctly and oil was being sucked into the combustion chamber. Lots of oil loss, but no leaks and very little smoke. Not sure if this is the case with your C-3, but thought I would share.
