Help I am Burning Oil...New Motor

[bdazzgt]

I built a new motor for my car it has about 25K on it, and it is starting to burn oil. It doesnt smoke all the time, and doesnt seem to do it at any certain point, ie idle or certain rpm's. It does puff out smoke when I shift and when i take off. What would cause this, a bad PCV valve? Maybe a valve seat ect? I cant do a leakdown because I had to pay college tuition this week and I dont have the $$. The shortblock was rebuilt with the .030 kit from summit with the forged pistons. The oil looks clean on a paper towel it isnt black. I am open for any ideas, I would like to get this fixed so I can sleep at night. It bothers me when new stuff isnt working correctly. Thanks again and let the ideas fly.


edit : How could i do a cost efficient leakdown? what tools do i need and how do i do it?

 

[bill302]

are you sure its burning oil? or burning rich what colors the smoke and are you having to add oil in between oil changes and how much...also i added some good info. on leak down and compression testing below.

want to do a leak down test do it yourself and build your own leakdown tester its not difficult click on link below for info...
http://www.xs11.com/tips/misc/misc3.shtml

plus heres some good info. about compression testing and if you want to do a compression test wal-mart sells a compression test guage with adapters for about $20
http://www.pumaracing.co.uk/comp.htm

 

[Roland69]

mine blows a bit of black smoke when I shift in the higher rpm's I think it has something to do with being SD

 

[rd]

You most likely don't have a big problem. The motor that I built in 87 burned a quart every 900 to 1500 miles for all the 95k miles I drove it. It is now running 12's in my toy, same rings. After 80k miles, the valve seals were tired, and I changed heads. Improved it greatly.

Ford's oem criteria allow up to a quart in 800 miles or something, as acceptable. A quart in 1200 or more is fine with me.

Some things to look for: If it smokes consistently after idling for a minute or so, or when decelerating it may be the valve stem seals, which are pretty easy to change. If the compression is ok and even across all 8, the rings should be fine.

As others said, it could be running rich under these conditions, which would be a fuel management item.

Unless it gets drasticly worse, just watch it, and test as you can.

 

[bdazzgt]

It burns about a quart every 1000 miles or so i know that is with in ford specs, but i dont like it. It is blowing blue smoke but the exhaust smells rich also, it seems to smoke at idle the most when sitting at a stop light, but it doesnt do it all the time which is what gets me. Then sometimes it starts smoking under acceleration. What i dont understand is why it just doesnt smoke constantly or at one certain RPM or somthing. Thanks keep the ideas coming.

 

[89white50]

my first thought was maybe the clearances for the piston skirt to wall weren't that great, or ring gaps were a little too large. It could also be a bad valve seal somewhere. or it could just be something stupid like being too rich, especially if you're running an offroad pipe. With how fast the ramp rates on sbf's its easy to dump out some raw fuel out of the tail pipes, or some carbon buildup in the chambers.

 

[bdazzgt]

I know i am running rich and i have a offroad H with a Comp cams extreme energy cam. From what I have read is that these cams have fast ramp rates. I dont know what is going on with it, i need to do a leakdown but as i said earlier i dont have the $$. Anyways can running too rich cause me to burn oil?

 

[Blandnuts]

Were the heads rebuilt? If so, what kind of valve seals were used and were the guides replaced?


Fred

 

[88stangmangt]

Were the heads rebuilt? If so, what kind of valve seals were used and were the guides replaced?


Fred

exactly.....valve seals being worn will cause bad puffs of smoke on take off,shifts and other weird times...........

 

[vristang]

Let's start with the easy stuff...

From my site, here http://www.freewebs.com/vristang/faqs.htm

Some theory on the PCV system.
The pcv is an emissions device that allows the pressure and corrosive gasses in the crankcase to vent, without venting these harmful gasses to the environment. The directional valve is in place to prevent a backfire from spreading to the crankcase. In the event of a backfire into the intake manifold, the pcv is supposed to seal shut, preventing the flame front from travelling into the crankcase. Without the directional valve in place and fully functional, a backfire would also cause a crankcase explosion.
All motors will experience some degree of blowby. Even a freshly rebuilt motor can experience between 5-10% of blowby, as checked with a Leakdown test. Blowby of combustion gasses introduces fuel and other combustion by products into the crankcase. Raw fuel, moisture, and various acidic materials will all contaminate the engine oil. Moisture can also enter the crankcase due to condensation overnight. The good news is that most of these contaminants are highly volatile, meaning they will vaporize at realatively low temps; around 200F. Once these contaminants and moisture have volatized though they must be purged from the crankcase. This is where a crankcase ventilation system comes in.
In the old days the crankcase was vented to the atmosphere via a hose that ran under the car or into the exhaust. The downside to this is that these volatile materials were being introduced to the atmosphere, increasing environmental damage. Now a Positive Crankcase Ventilation system is in use. In a positive venting system the crankcase contaminants are purged into the intake manifold so that they can be burned in the normal combustion process. This is very effective at reducing the amount of unburned HCs that are released to the atmosphere.
The downside is that when performance modifications are made to the motor, the stock pcv system can have trouble flowing the right amount of air from the crankcase. Excesive volumes of contaminated air flowing out of the crankcase, can pull excessive amounts of oil into the intake manifold.
Troubleshooting Your Oil Control Issues.​

The first step is to find out where the oil is coming from.
Pull the Throttle Body/Valve Cover hose from the TB. If it is wet with oil then this is an entry point. The normal causes of this are excess blowby (which needs to be ruled out with a compression test), or the VC baffle has been removed for rocker clearance. Just looking down the oil filler neck should reveal if the baffle is in place. If you see rockers, then it is time to get creative and fab a baffle. If there is no baffle but the TB/VC hose is bone dry then you may be able to get away without using a baffle.

Next pull the pcv hose. Again if it is wet with oil, this is an entry route. The best solution I have seen for this is a separator from Steeda, Home Depot, or Lowes. For about $25 (The Steeda unit will be more expensive) for the separator and fittings you will be able to remove most of the oil before it gets to the intake.
Also, you need to verify that the pcv screen is in place. This often forgotten part is located underneath the pcv in the back of the intake, and helps remove oil mist from the crankcase gasses.

From what I have seen, the oil accumulation in the intake will be greatest when the car is left to idle for some time (stuck in traffic or idling in the driveway), then with some rpm the oil is picked up and thrown into the combustion chamber. If you live in a humid part of the country, or see a fair amount of condensation on the ground in the morning, then you will most likely notice some moisture in the separator. This is fairly normal, as overnight condensation will form on the inside of the engine block. Once the oil gets up to temperature, this moisture boils off, and collects in the separator.

This is a pic I took of my engine at its worst. The car had been at idle for several minutes before I shut it off.
http://forums.stangnet.com/attachmen...8&d=1123979745

Hope this helps some,

Reference:
http://www.steeda.ca/catalogue_product_type_918.asp
Home Depot
This is the Fram pcv screen pn #BA8113
This is the NAPA pcv screen pn #6978

 

[vristang]

It wouldn't be a bad idea to pull the codes if you are definately running rich.

Excess oil in the exhaust can kill the O2s.
Running rich long term can kill the O2s as well.

jason

 

[jrod92]

Let's start with the easy stuff...

From my site, here http://www.freewebs.com/vristang/faqs.htm

Some theory on the PCV system.
The pcv is an emissions device that allows the pressure and corrosive gasses in the crankcase to vent, without venting these harmful gasses to the environment. The directional valve is in place to prevent a backfire from spreading to the crankcase. In the event of a backfire into the intake manifold, the pcv is supposed to seal shut, preventing the flame front from travelling into the crankcase. Without the directional valve in place and fully functional, a backfire would also cause a crankcase explosion.
All motors will experience some degree of blowby. Even a freshly rebuilt motor can experience between 5-10% of blowby, as checked with a Leakdown test. Blowby of combustion gasses introduces fuel and other combustion by products into the crankcase. Raw fuel, moisture, and various acidic materials will all contaminate the engine oil. Moisture can also enter the crankcase due to condensation overnight. The good news is that most of these contaminants are highly volatile, meaning they will vaporize at realatively low temps; around 200F. Once these contaminants and moisture have volatized though they must be purged from the crankcase. This is where a crankcase ventilation system comes in.
In the old days the crankcase was vented to the atmosphere via a hose that ran under the car or into the exhaust. The downside to this is that these volatile materials were being introduced to the atmosphere, increasing environmental damage. Now a Positive Crankcase Ventilation system is in use. In a positive venting system the crankcase contaminants are purged into the intake manifold so that they can be burned in the normal combustion process. This is very effective at reducing the amount of unburned HCs that are released to the atmosphere.
The downside is that when performance modifications are made to the motor, the stock pcv system can have trouble flowing the right amount of air from the crankcase. Excesive volumes of contaminated air flowing out of the crankcase, can pull excessive amounts of oil into the intake manifold.
Troubleshooting Your Oil Control Issues.​

The first step is to find out where the oil is coming from.
Pull the Throttle Body/Valve Cover hose from the TB. If it is wet with oil then this is an entry point. The normal causes of this are excess blowby (which needs to be ruled out with a compression test), or the VC baffle has been removed for rocker clearance. Just looking down the oil filler neck should reveal if the baffle is in place. If you see rockers, then it is time to get creative and fab a baffle. If there is no baffle but the TB/VC hose is bone dry then you may be able to get away without using a baffle.

Next pull the pcv hose. Again if it is wet with oil, this is an entry route. The best solution I have seen for this is a separator from Steeda, Home Depot, or Lowes. For about $25 (The Steeda unit will be more expensive) for the separator and fittings you will be able to remove most of the oil before it gets to the intake.
Also, you need to verify that the pcv screen is in place. This often forgotten part is located underneath the pcv in the back of the intake, and helps remove oil mist from the crankcase gasses.

From what I have seen, the oil accumulation in the intake will be greatest when the car is left to idle for some time (stuck in traffic or idling in the driveway), then with some rpm the oil is picked up and thrown into the combustion chamber. If you live in a humid part of the country, or see a fair amount of condensation on the ground in the morning, then you will most likely notice some moisture in the separator. This is fairly normal, as overnight condensation will form on the inside of the engine block. Once the oil gets up to temperature, this moisture boils off, and collects in the separator.

This is a pic I took of my engine at its worst. The car had been at idle for several minutes before I shut it off.
http://forums.stangnet.com/attachmen...8&d=1123979745

Hope this helps some,

Reference:
http://www.steeda.ca/catalogue_product_type_918.asp
Home Depot
This is the Fram pcv screen pn #BA8113
This is the NAPA pcv screen pn #6978

Does any one have pictures of homemade VC baffles? i am experiencing the same problem and i think i may need to make one.

 

[vristang]

Does any one have pictures of homemade VC baffles? i am experiencing the same problem and i think i may need to make one.

I have some at home, and will try to post them up tonight.
What I did is not pretty.
I used JBWeld to bond a thin piece of Al. to the inside of the valve cover.

If I had a welder and the skills to use it, I would have welded the baffle in place.

If I don't post them, pm me.

jason

 

[bdazzgt]

I took my car on a slew of tests today, it smokes at idle after it warms up and higher RPMS it doesnt smoke around the 2-4 k crusing range and after 4k and i shift it puffs out smoke and then clears up. What would cause this it sounds like a valve guide because if it was rings it would smoke all the time, correct?

 

[2000xp8]

Another easy fix would be intake gaskets, it happens more often then you think. There is 2 sets, one set does not work well.

 

[dragnazz5.0]

hey, dont feel too bad...my new motor didnt burn any oil until i figured out that i had an injector that was stuck open. i replaced it with a known good one and BAM! it started burning oil. probably a quart every 1k miles

 

[vristang]

I took my car on a slew of tests today, it smokes at idle after it warms up and higher RPMS it doesnt smoke around the 2-4 k crusing range and after 4k and i shift it puffs out smoke and then clears up. What would cause this it sounds like a valve guide because if it was rings it would smoke all the time, correct?

Did you check your TB/VC hose?
Did you check your PCV hose?
If there is oil inside one of these lines, then that is where the problem is.

Is there oil visible inside the manifold when you pull the inlet tube from the TB and peak inside?

Have you pulled the codes?

The combination of Intake vac and Crankcase pressure can result is puffs of smoke in almost nonsensical situations.

Once you have eliminated the above 2 hoses as the source of the problem, then it would be advisable to move on to checking the lower intake gasket, valve guides, and piston rings.

I suggest checking these lines first because they will be the easiest and cheapest to fix.

Imagine dropping a few hundred on rebuilding the heads just to find out that you didn't have a baffle on the valve cover?

jason

 

[88stangmangt]

I took my car on a slew of tests today, it smokes at idle after it warms up and higher RPMS it doesnt smoke around the 2-4 k crusing range and after 4k and i shift it puffs out smoke and then clears up. What would cause this it sounds like a valve guide because if it was rings it would smoke all the time, correct?

i would replace all the valve seals they arnt expensive then psot your results...you dont even have to take the head off to install them.

 

[Blandnuts]

Run the car for a bit at idle then shut it off. Let it sit for 10mins or so then start it up. If there's a puff of smoke right when you start it, it's probably valve guides/seals...



Fred

 

[bdazzgt]

Run the car for a bit at idle then shut it off. Let it sit for 10mins or so then start it up. If there's a puff of smoke right when you start it, it's probably valve guides/seals...Fred

That is exactly what it does, the TB and PCV hose doesnt have any moisture or oil at all in them. The baffles are on the valve covers also, but it smokes at start up, and then more at idle, after it was warmed up.