Oil Burping and you don't know why?

[MadTaz]

Just a heads up for those experiencing oil burping without a possible valid reason, well we had a customer in recently with this very issue, it turned out to be Racing Beat Oil Regulator. Once this was swapped out with an OEM all is well and he has yet to experience another burp.

I'd thought I'd just share this just in case it helps anyone out here.

[qwakers]

i too have random seeming oil burps but as i don't know the full history of the engine i don't know if I have a aftermarket regulator. do you have a quick easy way of checking?

[ChrisHolmes]

i too have random seeming oil burps but as i don't know the full history of the engine i don't know if I have a aftermarket regulator. do you have a quick easy way of checking?

What does your oil pressure go up to James after a cold start, that will be the blow off pressure of your relief valve. I have an RX7 valve in my engine and see 7bar when cold.

[ChrisHolmes]

Just a heads up for those experiencing oil burping without a possible valid reason, well we had a customer in recently with this very issue, it turned out to be Racing Beat Oil Regulator. Once this was swapped out with an OEM all is well and he has yet to experience another burp.

I'd thought I'd just share this just in case it helps anyone out here.

Interesting but I don’t understand how a lower maximum oil pressure would stop the oil burps, but clearly it has. The oil control rings in the rotors only see overflow oil and their isn’t anywhere else that highly pressurised oil can make its way into the intake or combustion chamber.
Every day is a school day!

[350matt]

I'm guessing the racing beat items have a higher pressure than normal ? so higher pressure = more flow squirting out of bearings and more likely to overwhelm a slightly tired side seal

[qwakers]

i too have random seeming oil burps but as i don't know the full history of the engine i don't know if I have a aftermarket regulator. do you have a quick easy way of checking?

What does your oil pressure go up to James after a cold start, that will be the blow off pressure of your relief valve. I have an RX7 valve in my engine and see 7bar when cold.

thats a good point.

no idea, ill tell you next time i start it

[MadTaz]

I'm guessing the racing beat items have a higher pressure than normal ? so higher pressure = more flow squirting out of bearings and more likely to overwhelm a slightly tired side seal

It's more to do with the position not the pressure, Mazda has designed some deflection of oil flow within the Rotor housings, the Racing Beat regulator bypasses that design.

[warpc0il]

Another example of "change isn't always for the better".

[ChrisHolmes]

I'm guessing the racing beat items have a higher pressure than normal ? so higher pressure = more flow squirting out of bearings and more likely to overwhelm a slightly tired side seal

It's more to do with the position not the pressure, Mazda has designed some deflection of oil flow within the Rotor housings, the Racing Beat regulator bypasses that design.

The Racing Beat one that I have is identical externally to the OE regulator how does it by-pass the OE design?

[Brundish82]

Not sure if posting in the right place but when doing the compression test the other day I had the catch can removed and put the hose from the filler neck back to the Intake system so today I go and do some stuff I notice oil in the intake from that hose, now I dont know if it had been overfilled with oil but as the compression is low would it be safe to assume its the side seals failing?

[Brundish82]

Run the engine with the oil filler cap removed.

With it idling, put your had over the hole and you should feel just the slightest pulsing.

If there is any significant positive pressure against your hand then, most likely the side seals are failing.
There are some other potential causes, such as cracks around the exhaust ports, but all would require a full engine strip to determine anyway.

[Brundish82]

Okay will give that a shot but will put all the airbox and stuff back in first as was idling funny but wasn't before, guess I have lots of jobs to do for this project lol

[Milos_Balunovic]

Much higher flow that the drain is not able to whitstand and than any gases push upwards

[Brundish82]

If it had a uprated regulator on is it possible this could be the issue for oil coming out of the breather hose?