I have a 2018 ram 3500 6.7 Cummins 24200 miles
I recently added a sinister diesel oil filter bypass to the motor it takes the oil from the top of the oil filter housing there is a plug you remove and add a fitting to connect a line to and it routs to the bypass oil filter housing that's mounted on a bracket furnished in the kit which is mounted to the engine block. From there a line takes the oil from the filter and returns it to the engine through the oil filler location at the front of the engine using a special cap provided.
After installing the kit I drove the truck for two days and noticed oil coming from underneath the truck and following the oil to the top of the engine coming from the CCV filter housing at the rear I cleaned all the oil off the engine and put shop towels in that area and drove the truck to verify that is where the leak was. The towels were saturated in oil. I cleaned the area again.
I removed the oil bypass from the truck and put it back to stock and drove the truck with no more oil leaks
My question is could the oil bypass system be pressurizing the engine causing the oil leak.
Bypass oil filter problem
- Thread starter mario49
- Start date
I have a similar one in my PSD and it works flawless. No leaks. Been on for 2 years or so. Who sells/manufactured the kit?
Sinister Diesel is the mfg also sold by them
My guess is that there's way too much oil flowing through the bypass filter and it's getting sprayed around inside the valve cover and some of it is ending up in the vent filter. Too much flow through the bypass could also mean not enough flow through the full flow filter and not enough flow to critical engine parts.
First step I'd take is a phone call to Sinister Diesel and see what they say.
My bypass filter came with a pancake adapter to fit between the oil filter and oil filter housing. It only allow a small about of oil to go to the bypass filter.
The plug you took out to install the line to the bypass filter housing could have been for many things. Maybe not even a bypass filter.
Originally Posted by Langanobob
My guess is that there's way too much oil flowing through the bypass filter and it's getting sprayed around inside the valve cover and some of it is ending up in the vent filter. Too much flow through the bypass could also mean not enough flow through the full flow filter and not enough flow to critical engine parts.
First step I'd take is a phone call to Sinister Diesel and see what they say.
Originally Posted by Donald
The plug you took out to install the line to the bypass filter housing could have been for many things. Maybe not even a bypass filter.
"My question is could the oil bypass system be pressurizing the engine causing the oil leak."
No. Unless you're returning the oil to the intake manifold or some place it REALLY should not be....You'd have such a mosquito fogger you'd shut it down in seconds if you didn't drown the combustion process in oil or hydrolock your engine, in which case I can't see you even getting it to start in the first place. Many others on BITOG (including myself) have run oil bypass filters for years and untold miles, leak and trouble free. Your leak is in the fault of your installation. Call me brutally honest if you wish, or prove me wrong?
Did not mean to imply that there is a problem with bypass filtration in general, obviously a lot of people have successfully run them, including me. There does appear to be a possible flow problem with this particular installation.
Nonissue. Flow thru the bypass filter is restricted not only by the size of the line that feeds it, but by restrictor orifices in the INPUT side of the bypass filter housings. I've been running 2-3 bypass filters for several years; no leaks and no engine oil starvation. I have a DIC that gives a digital readout of oil pressure in real time. If there were ANY bypass oil filter (or housing) manufacturer on the market capable of robbing enough oil flow to starve an engine, it would be all over the internet. Try Googling "engines blown up due to bypass filtration" and let us know your findings?
Originally Posted by Ihatetochangeoil
Originally Posted by Langanobob
My guess is that there's way too much oil flowing through the bypass filter and it's getting sprayed around inside the valve cover and some of it is ending up in the vent filter. Too much flow through the bypass could also mean not enough flow through the full flow filter and not enough flow to critical engine parts.
First step I'd take is a phone call to Sinister Diesel and see what they say.
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No sir. There was a LEAK. A leak is not a FLOW problem; it is a LEAK...The OP didn't tighten something sufficiently, or he didn't use a thread sealant, or he used a thread sealant on an AN fitting improperly...without the OP posting pictures or having lots more info such as the type of fittings, hose, and clamps used, it's all conjecture, but...SOMETHING is wrong with his INSTALLATION. The "sinister diesel oil filter bypass" system uses an Amsoil filter. https://www.google.com/search?q=sin...7j69i60&sourceid=chrome&ie=UTF-8
There are really only two hoses to run on a bypass setup, supply and return, with fittings on each end of both hoses, so there are only 4 hose connections necessary. The OP had a LEAK until he removed his kit. I have run an Amsoil system, a Kleenoil system, a Puradyn, an NTZ, and a Centrifuge. No leaks. Anywhere. I would not leave my driveway with a known oil leak.
I absolutely agree with Ihatetochangeoil.
Also, the port on top of the oil filter housing is a 1/8" NPT port. There are actually two ports there, and one feeds the oil line to the turbo. The other is plugged. This is a very common source for a bypass oil filter on Cummins engines, and in fact I use it in the bypass filter system on my truck.
Definitely the next step should be to call Sinister Diesel and get their advice.
Originally Posted by Ihatetochangeoil
No sir. There was a LEAK. A leak is not a FLOW problem; it is a LEAK...The OP didn't tighten something sufficiently, or he didn't use a thread sealant, or he used a thread sealant on an AN fitting improperly...without the OP posting pictures or having lots more info such as the type of fittings, hose, and clamps used, it's all conjecture, but...SOMETHING is wrong with his INSTALLATION. The "sinister diesel oil filter bypass" system uses an Amsoil filter. https://www.google.com/search?q=sin...7j69i60&sourceid=chrome&ie=UTF-8
There are really only two hoses to run on a bypass setup, supply and return, with fittings on each end of both hoses, so there are only 4 hose connections necessary. The OP had a LEAK until he removed his kit. I have run an Amsoil system, a Kleenoil system, a Puradyn, an NTZ, and a Centrifuge. No leaks. Anywhere. I would not leave my driveway with a known oil leak.
So I had the same leaking issues as you on my Ram. I ensured all connections and fittings we're tight but still leaked. I traced the issue back to the sinister cap. only thing I could determine is the seal on the cap is/was faulty. I just removed the entire system. I run a Baldwin self contained bypass filter anyhow (BP 7317) and planning on doing some upgrades to the truck in the near future.
Just figured I let you know your not the only one that had these issues with the kit.
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Just added pictures to show where my BP was leaking. Leaking can be seen on the front of the valve cover and would continue to the rear as seen in the third picture. The sinister cap shows no external leaking or cracks. I degreased the upper engine, drove it about 30 miles and the pictures above are the result. This made me determine the cap (gasket or a defect inside the cap) was the issue. Tried previous attempts at ensuring the cap wasn't over tightened or to loose btw.
Since removal the leaks have stopped.