Probby Posted February 3 Share Posted February 3 Hi folks, Curious but when you guys change your oil do you pull the fuel pump fuse and turn the key until the oil pressure light goes out to ensure you have oil pressure before running the engine? If I wanted to do that, is it enough to pull the 30AMP EFI fuse to achieve this or are there better options ? Thanks Quote Link to comment Share on other sites More sharing options...
AC93 Posted February 3 Share Posted February 3 Yeh I pull the EFI fuse, crank it for a seconds then good to go 1 Quote Link to comment Share on other sites More sharing options...
Probby Posted February 3 Author Share Posted February 3 Cheers AC93, not sure how relevant it is with these engines but I figure better be safe than sorry! Quote Link to comment Share on other sites More sharing options...
Swampy442 Posted February 3 Share Posted February 3 No, Ive never done that on any vehicle Ive ever owned, when Ive changed a turbo yes but not the oil. Quote Link to comment Share on other sites More sharing options...
Probby Posted February 3 Author Share Posted February 3 Always done it is a bit of an (likely unnecessary) precaution. Coming from a Subaru background they need no excuse to spin/pop something so just something I've always done ! Quote Link to comment Share on other sites More sharing options...
rider Posted February 3 Share Posted February 3 (edited) Oil films are retained on metal surfaces for up to a month. There are additives common in engine oils that attract/bind the oil to a metal surface for the sole purpose of film retention on standing. Castrol pioneered a lot of this work in the 90's and they were so proud of the new oils they marketed them under the Magnatec brand with illustrations of oil bonding to metal. The seeping away of the oil film is logarithmic with time, not linear. So you could drain your oil on a Monday and refill on a Friday and the oil film will still be 30% there from the retained old oil. If you return to a car that has sat overnight and start it up only 45% of the oil film will have been retained at that start up. So there isn't much difference overnight to several days standing, because of the logarithmic time bleed on film thickness. Edited February 3 by rider (see edit history) 2 Quote Link to comment Share on other sites More sharing options...
Mike2JZ Posted February 3 Share Posted February 3 More important is to prime the oil filter by filling it with oil before fitting. I've tested back to back with and without this, and looking at oil pressure logs there is a small delay without priming the filter where engine spins without oil pressure. We are only talking about 1-2 seconds, so not likely to be that big of a deal given riders point above, but if you wanna be anal then i'd prioritize that over priming the system by spinning it over without starting 3 Quote Link to comment Share on other sites More sharing options...
Probby Posted February 3 Author Share Posted February 3 1 hour ago, Mike2JZ said: More important is to prime the oil filter by filling it with oil before fitting. I've tested back to back with and without this, and looking at oil pressure logs there is a small delay without priming the filter where engine spins without oil pressure. We are only talking about 1-2 seconds, so not likely to be that big of a deal given riders point above, but if you wanna be anal then i'd prioritize that over priming the system by spinning it over without starting I do this too ... amazing how much the filter takes on its own. Cheers for all your responses Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.