Discussion and questions related to the course Practical Engine Building
Every Nissan i've worked on has a bypass valve behind the oil filter. Every mechanic tells they open when the filter would get blocked.
my intention was to remove the valve and block it , since thats one engine killer less when it fails.
However : I had a chat with an engineer at Donaldson and he mentioned that cold oil always bypasses the filter. if there was no valve ,the filter medium would collapse due to the high viscosity when cold.
i've never heard of this , this would explain why you drain the oil when running in a new engine (you would use the oil unfiltered in the first minutes at the second cold start).
Anyone some input on this topic ?
truth. Don't remove an oil bypass. Blowing up the oil filter with a rev when cold is really no fun to clean up.
It's a safety valve, by all means test and make sure it works but don't remove it as it'll blow your filter and/or seals
ah good to hear