Engine blow-by question???
Thread Starter
|
Senior User
Joined: Aug 2007
Posts: 199
Likes: 0
Engine blow-by question???
I have asked this before on another forum, but didn't really get any answers. I sort of have a favor. My truck has, what I would call a fair amount of blow-by. It is an 08 6.4, maybe 2-3 times more than my 6.0 had. It is enough that if I set the oil cap loosely on the filler, and then rev it it blows off. At idle it wisp's out a fair amount as well. Would anybody mind checking to see how much blow-by comes out of your oil cap? I thought it was supposed to be a tiny amount, like my 6.0 had. Just trying to find out if there is a problem.
Thanks..
Thanks..
Senior User
Joined: Jun 2006
Posts: 460
Likes: 1
From: South Mississippi
I wouldnt think thats good i own a 7.3 and mine does it because someone abused my engine. If it puffs like a train your engine is eventually going to fail and loose compression. I would try to get ford to replace it if i were you
Thread Starter
|
Senior User
Joined: Aug 2007
Posts: 199
Likes: 0
So I can't believe that I would get a truck with a bad engine already! Is it possible that since my truck has the oil separator built in, that it all comes out there, and none through the intake????? Thanks
Post Fiend
Joined: Jan 2009
Posts: 6,521
Likes: 11
From: Greenwood, SC
The idea of taking the oil filler cap off of my engine while running seems highly unusual and I think that nobody would do that, so the blow by, if it exists is something that none of us would discover.
I might try it some time and i'll let you know.
I might try it some time and i'll let you know.
Thread Starter
|
Senior User
Joined: Aug 2007
Posts: 199
Likes: 0
Actually, I thought that was a common way to check blow-by?? The reason I checked it on my new truck, is because I was curious to see if it had as much as my 6.0 did, and it had more, so that's why I asked this question. It doesn't seem right, but I was thinking that the 6.4 might run on less compression or something.
Posting Guru
Joined: Jan 2006
Posts: 1,513
Likes: 1
I know every engine has a degree of blow by, thus the reason for a PCV system. I havent made it a practice to compare blow by between engines by removing the oil cap and with the sophistication of today's engines Im not entirely sure that is an accurate measure of "blow by". These new engines are designed to burn and reburn in the name of emissions. On a gas engine I know crankcrase pressure (which is really what you are experiencing by removing the oil cap) can be altered by the size of the camshaft, the amount of vacuum, whether you run a breather or a PCV system, etc, etc.
I think if you have a true blow by issue on your 6.4 you will experience low boost and/or poor performance. As your boost builds your blow by would get worse and at full boost your crankcrase pressure would be so great that you would be ingesting oil in to the system and probably smoking.
One of the performance tricks on 7.3's and 6.0's is to re-route the blow by tube to the rear of the truck rather than it being fed back in to your intake. I believe there are more in depth threads on this in the tech section of both the 7.3 and 6.0 forums that might provide you with more details pertaining to your concern.
I think if you have a true blow by issue on your 6.4 you will experience low boost and/or poor performance. As your boost builds your blow by would get worse and at full boost your crankcrase pressure would be so great that you would be ingesting oil in to the system and probably smoking.
One of the performance tricks on 7.3's and 6.0's is to re-route the blow by tube to the rear of the truck rather than it being fed back in to your intake. I believe there are more in depth threads on this in the tech section of both the 7.3 and 6.0 forums that might provide you with more details pertaining to your concern.
Trending Topics
Thread Starter
|
Senior User
Joined: Aug 2007
Posts: 199
Likes: 0
FTE Stories
Ford Trucks for Ford Truck Enthusiasts
Top 10 Fords at 2026 Carlisle Ford Nationals
Joe Kucinski
3 Best / 3 Worst Parts of Modern Ford Ownership
Brett Foote
10 Amazing Upgrades That Solve Common Ford Truck Owner Headaches
Pouria Savadkouei
Every 2026 Ford Engine Explained
Brett Foote
10 Ugly Ford Trucks That We Still Kinda Love
Joe Kucinski
10 Things Every Truck Owner NEEDS (2026 Edition)
Michael S. Palmer
Rezvani's Latest Post-Apocalyptic Monster Is a Ford F-150 Raptor Underneath
Verdad Gallardo
Top 10 Most Expensive Ford Trucks Ever Sold on Bring a Trailer
Joe Kucinski
2027 Ford Super Duty Buyer's Guide (Every Model, Engine, & Package)
Brett Foote
Thread
Thread Starter
Forum
Replies
Last Post
CISKOWSKI_21
6.4L Power Stroke Diesel
18
Apr 20, 2020 07:54 PM
DieselCamper
1973 - 1979 F-100 & Larger F-Series Trucks
3
Aug 15, 2016 11:36 PM
