getblown5.9

I'm just north of the 500hp mark and I am wondering if its a common occurence to get alot of blowby out of the bottle/tube when running trucks in the 50+ psi range and higher rpms?

My truck pulls hard thru 3500rpms so thats how far I will take it when playing around, but I'm wondering if those high rpms and high boost is what is causing my excessive blowby.

the bottom of my oil pan and the whole left/drivers side of the motor is coated with oil, and its always fresh, but i get ZERO drips on the ground, and its just a light film from midway up the block down to the oil pan and bellhousing.

I've searched for a leak when on the lift and cant find anything, vacuum pump seal is good now, not leaking there, i'm 99% positive i'm getting a blowby spray out of the bottle when running it hard, so i am going to ditch the bottle and extend the hose all the way down below the motor so it will push the blowby out to the ground rather than all over my motor.

dzlfarmboy

High hp with high boost will cause this mine does it too

mysterync

I get a light haze but havent even had a puddle or drips, After a hard pull its normal to see the truck breath or steam!

getblown5.9

i never get drips or puddles either but working under the truck is a pain because there is oil on everything.

at least it wont rust

pokapotato

Blowby is caused by pressure going past the piston rings, mixing with oil and coming out the blowby or breather tube. The more pressure in the cylinders the more blowby you are going to have. If you have ever watched the John Deere and International tractors pull, their blowby looks like a second exhaust. Of course they are running 100 psi or more boost. I have done away with the breather bottle on mine and I ran a hose right out the bottom. I get drips on the floor in the garage. This is all normal. I would be concerned about excessive blowby when idling, and or if visible cyclic puffing can be seen in the blowby.

Gotlift01

Yeah I think it's just the nature of the beast, push em that hard and it's gonna do it. I guess you could always try doing the relocate mod and dump the blowby behind the motor.....that way the motor stays clean.


~Nick

getblown5.9

im just gonna run the tube down far enough that it dumps below the motor, don't feel like adding more stuff/tubing up over the motor like alot of guys do.

dzlfarmboy

yeah i got mine running down and it goes about a 1" below the front axle keeps things pretty clean

mcoleman

Wonder how a crankcase evac system would work with a 1 way valve in the downpipe? That would actually pull gasses out of the engine like we always did with race engines. You actually gain HP on a gas engine doing this.

Gotlift01

I can't say that I blame you......I don't really care for the looks of it either, but it would help keep things clean. But a longer tube should work just as well.



~Nick

ratsun

There was a thread a long time ago where Forrest tried it and it didnt work so good. I dont know if he used the 1 way valve or just run the breather tube to the exhaust?

Lil Dog

I know a fellow from NWBombers who put a pipe into his exhaust with slight elbow on it. The exhaust flow past the elbow facing downstream causes negative pressure and would draw on the tube harder as the flow increases. This was on a 5" pipe on twins. Seemed to work OK...

ratsun

Here the original thread
https://www.dieseltruckresource.com/...ad.php?t=61348

I dont remember the details other than it didnt work as expected?

ct2500

loose the breather bottle and stick a peice of 3/4 hose all the way down to front axle. when i got my truck the previese owner nerver cleaned puke bottle and it pickled my radaitor more than 50% had to remove it and clean with degreeser and presser washer. but all diesel engines breathe if its nite time and i look at my blow by with a flash lite it looks real bad but durin day u can barly see it.

Madgaffer

most dealer around me remove the bottle the first time anyone complaines
about an oil leak. Shoot in my case they removed it before they even looked
for an oil leak took three visits to the dealer before i got under the truck myself and pointed out to them it wasn't oil but power steering fluid. They just
dump a hose down and leave it were it lay. Mine is right on the pumpkin and with just banks power pack no major extra boost it coats the engine compartment and puffs away plenty