Valve cover gasket was done 3 1/2 years ago along with front main seal, ofhg was done 2 years ago. The n52 is available in various models, each with its own set of features and packages. So that leaves possibility either they are failing, or perhaps vanos o rings.
BMW N52 Bad Camshaft Ledge Seals, The Root Cause Of The Ticking YouTube
It will tell you if it is a valve problem or piston/ring problem.
If it passes the leak down test (probably won’t if low compression) move to something else.
It probably won’t pass it but depending on where it is leaking, that will help you figure out the problem. I did a leak down test on my n52 awhile ago. Only 5 and 6 tested barley within limits. So i dont think i have a piston ring issue.
Its in 5 and 6 i see the blueish color on the valve stem. If the dry numbers are bad, and they don't improve on the wet test, that means the valves are leaking. You could do a leakdown test and see which valves, but it doesn't matter which valves at that point; The head has to come off, and then you lap or grind the valves to fix it.
If you have stuck rings, it should leak much quicker on your weak cylinder.
If that is the case, use a stronger cleaner to ‘soak’ the rings to try and free them up. Seafoam may be one product to try. Hi, has anyone done a leak down test on a n52 engine, i'm wondering if there is a specific value that's acceptable per bmw's. In theory >20% is bad, but i've read threads were even 30% is decentnot sure if that's accurate.
Have not yet diagnosed the source of the oil leak in my n52. Valve cover gasket was done 3 1/2 years ago along with front main seal, ofhg was done 2 years ago. So that leaves possibility either they are failing, or perhaps vanos o rings. It will tell you if it is a valve problem or piston/ring problem.
If it passes the leak down test (probably won’t if low compression) move to something else.
It probably won’t pass it but depending on where it is leaking, that will help you figure out the problem. I did a leak down test on my n52 awhile ago. Only 5 and 6 tested barley within limits. So i dont think i have a piston ring issue.
Its in 5 and 6 i see the blueish color on the valve stem. If the dry numbers are bad, and they don't improve on the wet test, that means the valves are leaking. You could do a leakdown test and see which valves, but it doesn't matter which valves at that point; The head has to come off, and then you lap or grind the valves to fix it.
If you have stuck rings, it should leak much quicker on your weak cylinder.
If that is the case, use a stronger cleaner to ‘soak’ the rings to try and free them up. Seafoam may be one product to try. Hi, has anyone done a leak down test on a n52 engine, i'm wondering if there is a specific value that's acceptable per bmw's. In theory >20% is bad, but i've read threads were even 30% is decentnot sure if that's accurate.
The n52 was predominately found in the e90 325i, 328i, 330i, and the e60 525i and 528i models, as well as various others such as the 128i, x1, and z4, to name a few. The n52 was produced from 2004 until 2015 when it was replaced by the turbocharged n20 engine. It is the successor to the m54 which was used in various e36, e39, and e46 models. My 09 n54 oil cooler/filter housing o rings were leaking and oil was seeping down the front of the engine.
That may be similar to what your car is doing.
I replaced all of them and cleaned the front of the engine. Looks like new now and no issues with leaks. Wow, inflation or profit padding sure is getting bad. Then again, bmw did a very poor job sealing these engines when compared to audi.
The pan gasket and oil level sensor gasket for rwd were like $30, plus aluminum bolt sets , permatex rtv and such. If the pressure drops right off, that is a sign of a leak. Look for coolant on the ground. If no coolant reaches the ground, you could have an internal leak.
If you suspect a head gasket leak, you need to test cylinder sealing via a leak down test.
It’s possible for the filter cap to leak if the o ring has hardened or is of low quality and this produces a pretty substantial leak. The filter housing gasket is also a common leak, between the housing and head and it’s pretty straight forward to clean and replace. Bimmerforums is the preferred online bmw forum and community for bmw owners. Our professionals are here to help make sure you find the answers you need to your questions and our community is here to help other brainstorm
If you didn't replace at least the ones for the injector to the cylinder head, i'd go ahead and do that as a minimum. I'd also release and inspect the fuel hose to the fuel rail and the fuel rail connector. Have not yet diagnosed the source of the oil leak in my n52. Valve cover gasket was done 3 1/2 years ago along with front main seal, ofhg was done 2 years ago.
So that leaves possibility either they are failing, or perhaps vanos o rings.
Its also the first time i used ow30 oit when oil changed 1 N52 engines are pretty reliable when maintained. This one has pretty low miles to be having this kind of trouble. Also you mentioned timing…that could also cause an engine to fail a leak down test but i think it would show up on multiple cylinders.
The way you test is is by doing wet and dry tests and comparing numbers. If the dry numbers are bad, and they don't improve on the wet test, that means the valves are leaking. You could do a leakdown test and see which valves, but it doesn't matter which valves at that point; The head has to come off, and then you lap or grind the valves to fix
I did a leak down test on my n52 awhile ago.
Only 5 and 6 tested barley within limits. So i dont think i have a piston ring issue. Its in 5 and 6 i see the blueish color on the valve stem. Hi, has anyone done a leak down test on a n52 engine, i'm wondering if there is a specific value that's acceptable per bmw's.
In theory >20% is bad, but i've read threads were even 30% is decentnot sure if that's accurate. Have a 06 325i with a n52 engine that is foreign to me. The car would idle great until you tried to drive and then it would go into limp mode. This was 6 months ago when i got this car and remember that it had a code for cylinder 5 and also a 02 sensor code.
I had did a compression check a #5 was down about 40lbs.
Compared to other 5 cylinders.
