Oil Pressure

Woodie1

Woodie1

Well-known member
We have a person in our club who put a Burtz engine in his car. He has followed their recommendations in the assembly. He has modified the oil pump to give 9 lbs. when warm. He is having blow by problems with a lot of oil dripping off the pan. Do you think he has too much oil pressure? I van't give all the details as I didn't do the work.
 
No
9 # pressure at idle warm is not the issue
Is there blowby pressure building up in crankcase?
Other issues are likely such as loose oil fitting or even valve chamber cover gasket leaking J
 
A new Burtz engine will have back pressure resulting in oil being pushed out the filler tube and landing on the side of the engine. The reason for this is the piston rings have not yet seated. They can take up to 3,000 miles to seat. Your best bet to keep your engine clean is to install a fumaze. It is installed into the filler tube and is connected to a flex pipe that goes below the frame to discharge the oil mist.

Oil pressure can be 5-10 lbs. at idle. However it should have 20-30 lbs. when running down the road at 50-55 provided you have the high pressure oil pump.

You state the oil pump installed was modified to produce 9 lbs. If that is the case, I think it is doubtful the oil pressure is pushing oil out of the pan.

Just a thought, if compression is leaking into the crank case due to the piston rings not seating, that can definitely push oil out of the pan. Your cylinders are each producing around 90 lbs. of compression. If they are leaking compression, it will pressurize your crankcase.

Drive it and things will improve...
 
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Terry Burtz needs more information regarding the build. One of the "New Engine" builders aligned the ring gaps, lubed the rings with 90w gear oil, and had lots of blowby. Please ask the builder the following questions.

Were stock pistons with wide rings used?
Were Egge or Silvolite pistons with narrow rings used?
Were the ring gaps staggered or in alignment?
Was 90w gear lube used to lubricate the rings?
Are the rings installed upside down?
Was the plateau cylinder wall finish re-honed or bored larger?
Does the oil filler tube fit tight into the cylinder block?
Was a sealer used between the oil filler tube and cylinder block?
Was the upper surface of the oil pan straightened to be flat?
Were the oil pan attachment bolts overtightened?
Was the cork strip at the back of the oil pan cut too short?
Was an oil pan gasket set that does not contact the front seal used?
Was any gap between the short gasket and front seal filled with the "Right Stuff"?
Does the front pulley have a groove where the seal rides?
Is the crankshaft slinger in place?
If a front radial lip seal was used, was a sealant used on the exterior?
Does the oil pan drain plug have a sealing washer?
Is the valve cover gasket leaking?
Were the surfaces that need sealant cleaned with mineral spirits, diesel, or acetone?
 
Get some miles on the engine and the blow by problem will probably resolve itself.

As previously stated, you have to be sure the rings are seated before you start to worry about blow by.

My experience,

Chris W.
 
What Terry is saying is that the narrow rings will seat faster. The Burtz block is harder that the original block and takes longer to break in.

If you have a Burtz engine, buy and install the oil deflectors from Terry. They will help control the oil mist in the valve chamber that can cause excessive oil consumption from the oil being sucked up between the intake valve stems and their guides.
 
nkaminar said:
What Terry is saying is that the narrow rings will seat faster. The Burtz block is harder that the original block and takes longer to break in.

If you have a Burtz engine, buy and install the oil deflectors from Terry. They will help control the oil mist in the valve chamber that can cause excessive oil consumption from the oil being sucked up between the intake valve stems and their guides.
Click to expand...

That is the most likely reason for your problem. The amount of oil pressure has absolutely no effect on oil usage, I run 40 lbs. on my street engines and 60 on my race engine, no usage problems.
 
Are the rings in upside down is my favorite question. Followed by what the person feels the need to modify the oil pump.
 
It's always a good idea to stagger the ring gaps when assembling an engine but when an engine's running the rings actually rotate so this gaps become aligned and staggered at various times so it really doesn't matter!!!
 
If you've ever disassembled a 2 cycle engine you'll notice the rings are pinned in the pistons so they don't rotate because the edge of the rink can get caught in a intake or exhaust port and break they really do rotate when an engine runs most likely the effect is from vibraration.
 
Fullraceflathead said:
If you've ever disassembled a 2 cycle engine you'll notice the rings are pinned in the pistons so they don't rotate because the edge of the rink can get caught in a intake or exhaust port and break they really do rotate when an engine runs most likely the effect is from vibraration.
Click to expand...

GM diesel 2 stroke, series 71 engines do not have "pinned" piston rings.
 
The question of why do rings rotate / what forces would cause this was also discussed at length on a motorcycle forum. The consensus (for what that’s worth) was that no one had scientific proof of the cause.
 
If rings are suspect, run a wet dry compression test, that should answer any questions of ring seat or non seat, if all is good move to other possible cause, although I have found broken rings in new engines and some crystalized due to running hot while on the test stand without the cooling system connected.
 
Some two cycle engines have vertical segments of the bore that are not cut out for the ports so that the rings can rotate and not get caught.
 
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Hello, Hudson and Rolls Royce were also use pinned rings. Normally ring gaps are set 120 degrees from each other on assembly, and also as asked in other post are the rings installed right side up ? Generally a slight groove is on upper face of ring .The theory is at combustion the gas will push the ring closer to the cylinder wall , easy to get them in upside down. Good luck, please let us know what you find out.
 
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