hey guys I'm new to this site but have been around the cumins motors in heavy and light duty applications for a long time. I have been wondering about something for a while now. Had a thought to put an electric smog pump off of a late 90s early 00s gm car or truck on my 96 cummins to reduce crankcase pressure. What do you think? Good idea or bad? I know the trucks have a blow by tube to relieve the pressure but what if I did the pump to suck the crancase down to negative pressue. Wouldn't be enough to hurt anything just a few psi maybe 5-7 max. And it would prolly help with oil leaks to. I run one on my elcomino drag race car and it works great if it doesn't turn on I loose a tenth of a second just by it not working. So give me your thoughts any input is appreciated.

 

It's not as critical in a diesel because they don't turn the rpm's that a gas engine does. Be interesting to see if a vac on the crankcase had an effect anything else... Only issue I see is that it might pull more oil through the turbo??? Maybe?

 

ya I understand what you meen about lower rpm. But I was thinking about this because of the boost pressure creating crankcase pressure. How would it pull more oil into the turbo?

 

The turbo drains into the oil pan just under regular gravity. There is an orifice usually in the turbo on the pressure side of the oil line to help control flow. If you create a vaccuum in the oil pan though, it will try to pull this oil through the turbo as well.

Also on a reliability side, you'll have to seal the engine up to be able to create this vaccuum, what happens if the pump burns out or blows a fuse going down the road.

I think the "keep it simple" rules apply... atleast if it's your daily driver.

 

ok I get it now I didn't even think about that. And ya I think you are right why try to improve something if it works fine the way it is. Thanks for your input.