OIL restrictor// How small is too small???
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From: Wichita Falls, TX
OIL restrictor// How small is too small??? I have been reading and reading threads today about oil restrictors lots of good data but nothing that deals with this combo.
What I have is a T105 Thumper turbo 408sbc that I just can not stop a little smoke coming from.
The turbo is fed with a 1ft -4 line right off the oil filter(this is a dry sump pump). I am using the front suction to pull oil from the valley area, and the turbo return which is a 8" -10 line aimed down.
At cold idle about 90psi, once all things warm up gets down to 60 or so. I had a .081 then a .072, .062,.052 and now sitting at a .046. Still some oil in the DP,
So I took the DP off and just ran it wide open. Wanted to see if I could see the problem.
Idle no smoke no oil,,,,, Zing the engine a little puff, nothing big. A couple or more times puff gets a little bigger, and I can see a little wetting on the outlet vband area. Inside the turbine housing also seem damp/shiny. Not normal I know.
So I pulled the gate, the hot pipes leading up to the turbo are carbon dry, no oil. So engine is fine, as it should be its a NEW engine, lol.
I called Turbonetics and ask what was this turbos oil requirments, the responce
" thats a tough one to answer"
The turbo is 4 years old, but never ran for 3.5 years, so I would still call it new.
So how small is too small.
BTW there is a HUGE diffence in oil drain from a .081 to the .052. But still the .052 could fill a quart bottle pretty dam quick.
Any help would be appreciated, I do not want to smoke this turbo YET, but its time is coming.
What I have is a T105 Thumper turbo 408sbc that I just can not stop a little smoke coming from.
The turbo is fed with a 1ft -4 line right off the oil filter(this is a dry sump pump). I am using the front suction to pull oil from the valley area, and the turbo return which is a 8" -10 line aimed down.
At cold idle about 90psi, once all things warm up gets down to 60 or so. I had a .081 then a .072, .062,.052 and now sitting at a .046. Still some oil in the DP,
So I took the DP off and just ran it wide open. Wanted to see if I could see the problem.
Idle no smoke no oil,,,,, Zing the engine a little puff, nothing big. A couple or more times puff gets a little bigger, and I can see a little wetting on the outlet vband area. Inside the turbine housing also seem damp/shiny. Not normal I know.
So I pulled the gate, the hot pipes leading up to the turbo are carbon dry, no oil. So engine is fine, as it should be its a NEW engine, lol.
I called Turbonetics and ask what was this turbos oil requirments, the responce
" thats a tough one to answer"
The turbo is 4 years old, but never ran for 3.5 years, so I would still call it new.
So how small is too small.
BTW there is a HUGE diffence in oil drain from a .081 to the .052. But still the .052 could fill a quart bottle pretty dam quick.
Any help would be appreciated, I do not want to smoke this turbo YET, but its time is coming.
Sounds like a drain issue to me. The oil is backing up in the turbo. Check for blockages or try running a 3/4 hose for your drain for testing purposes. I've had trouble with a #10 being too small for the drain in the past. I'm unsure of how much oil needs to be fed to that turbo, but back in the day, we would feed with a #3 no restrictor and return with #12.
it may be an oil drain problem like stated. Do you have a spare scavenge pump or something like that lying around. I would try and make up a small test setup and run it like that.
I did it on my setup and was able to conclude that the drain was a problem. It would fill the downpipe with oil, but as soon as the scavenge pump went on..it was nothing.
If oiling is the issue..i would try and put a return and regulator on the feed line. You could still have lower oil pressure but flow could still be way too much. turbos dont really need a lot of volume.
I did it on my setup and was able to conclude that the drain was a problem. It would fill the downpipe with oil, but as soon as the scavenge pump went on..it was nothing.
If oiling is the issue..i would try and put a return and regulator on the feed line. You could still have lower oil pressure but flow could still be way too much. turbos dont really need a lot of volume.
Thread Starter
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From: Wichita Falls, TX
I am going to pick some clear hose from the hardware store, so I can see if the oil filling up or not. I donot have a spare dysump pump, they are not cheap.
Going to play it a little more today.
thanks
Going to play it a little more today.
thanks
