oil temp with twins
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Wow Good Thread!!:thumb:
Oil temp with twins is something that never crossed my mind before as being an issue, but it makes sense.
Is there any reason a guy couldn't just buy a Seatrab cooler like Mike L's trans cooler, run the drains from the twin/triple to it and mount it in front of the radiator? Then have it drain from there into the pan? It should gravity drain all the way from the turbo to the pan if there is no check valve. Worst case, put a "T" in the line on the outlet of the cooler to drain it. You may have to add an extra liter of oil or so to make up for the extra plumbing and cooler but whatever, not a big deal IMO.
Oil temp with twins is something that never crossed my mind before as being an issue, but it makes sense.
Is there any reason a guy couldn't just buy a Seatrab cooler like Mike L's trans cooler, run the drains from the twin/triple to it and mount it in front of the radiator? Then have it drain from there into the pan? It should gravity drain all the way from the turbo to the pan if there is no check valve. Worst case, put a "T" in the line on the outlet of the cooler to drain it. You may have to add an extra liter of oil or so to make up for the extra plumbing and cooler but whatever, not a big deal IMO.
Oil drains have to be free flowing to keep oil from backing up in the turbo's and getting past the seals or destroying them. Through a cooler is not free flowing at all, here is something to think about some twin kits drain strait to the pan and there is no cooling of that oil at all. On some of trents kits (not supporting trent never bought from him) the oil returns to the valve cover and the oil is getting a little bit of cooling from the engine surfaces on the way back down to the pan how much who knows but I'm sure it helps. I'm not so sure the oil heating problem is from the actual second turbo as much as I think its more the increase heat load on the pistons heating the oil, even though egt's are down to a more acceptable level there is way more engine load with the twins you think your safe now cause your egt's are lower so you throw more fuel at it 
Oil drains have to be free flowing to keep oil from backing up in the turbo's and getting past the seals or destroying them. Through a cooler is not free flowing at all, here is something to think about some twin kits drain strait to the pan and there is no cooling of that oil at all. On some of trents kits (not supporting trent never bought from him) the oil returns to the valve cover and the oil is getting a little bit of cooling from the engine surfaces on the way back down to the pan how much who knows but I'm sure it helps. I'm not so sure the oil heating problem is from the actual second turbo as much as I think its more the increase heat load on the pistons heating the oil, even though egt's are down to a more acceptable level there is way more engine load with the twins you think your safe now cause your egt's are lower so you throw more fuel at it
Have you ever measured the pressure drop across different styles of coolers?
Return oil from turbo's cannot have any oil backing up into the bottom of the turbo, what do you thinks going to happen on startup with cold oil in that cooler? Give it hell and let us know what happens not trying to argue or be rude just trying to help, get on Garrett or Borg Warners website and read up on turbo installation.
Here is a passage I just copied from Garretts turbo system optimization article.
Oil Drain
In general, the larger the oil drain, the better. However, a -10AN is typically sufficient
for proper oil drainage, but try not to have an inner diameter smaller than the drain hole
in the housing as this will likely cause the oil to back up in the center housing. Speaking
of oil backing up in the center housing, a gravity feed needs to be just that! The oil outlet
should follow the direction of gravity +/-35° when installed in the vehicle on level
ground. If a gravity feed is not possible, a scavenge pump should be used to insure that
oil flows freely away from the center housing.
Avoid:
• Undulations in the line or extended lengths parallel to the ground
• Draining into oil pan below oil level
• Dead heading into a component behind the oil pan
• Area behind the oil pan (windage tray window) where oil sling occurs from
crankshaf
Your missing my point. Not all coolers will cause a restriction to flow. If you can get a cooler that will flow a certain amount through it freely with strictly gravity doing the work, but restricting it just enough to allow it to fill up but not overflow, it would cool and work fine. Plus if you have the vertical column in the hose between the turbo and the cooler to allow for fluctuations in flow rate, and IF you get it right, it won't fill up right to the turbo. But your right, temperature and viscosity of the oil would definetly cause an issue at cold start up making this an un-reliable set-up.
And I guarantee you can have a little back pressure in the turbo drain without causing an issue. I've seen it first hand. A CAT C15 where somebody had made gaskets for the turbo oil supply and drain by hand and made the holes in both gaskets almost the same size as the supply. It ran for 2 years like this and when we pulled it off to replace a cracked exhaust manifold, we found the mistake. Turbo was pumping no oil into the air/exhaust at all though. It was a BW turbo.
But to be safe one could just do what garrett suggests then-use a scavenging pump with the cooler. It might take a little searching to find the right one, but I'm sure it can be done.
I'd like to know how the guys that have remote mounted turbos plumb in their drains. They sit quite low in relation to the block yet don't seem to have any issues that I have heard of and I would think there has to be some pooling going on.
But to put the knife in the heat issue altogether, as Hondarider suggested he wanted, the easiest fix is probably to route the drains into the upper oil pan as one normally would and install a secondary oil/air cooler in front of the stack and use one of the oil ports in the block to supply it with oil. Providing there is enough restriction in the aux cooler to still be able to maintain oil pressure in the engine it would work fine.
When I get my triples installed, I plan to do some testing of the back pressure in the oil drains, just out of curiousity sake and see how high I can take it before it starts leaking past a seal. I know Simon had well over 100psi going to his turbo's on the supply side before they started leaking and it had to be pressurizing the center section!! He had to install gauges and ball valves to control the flow to the turbo's till he got the issue sorted out!
And I guarantee you can have a little back pressure in the turbo drain without causing an issue. I've seen it first hand. A CAT C15 where somebody had made gaskets for the turbo oil supply and drain by hand and made the holes in both gaskets almost the same size as the supply. It ran for 2 years like this and when we pulled it off to replace a cracked exhaust manifold, we found the mistake. Turbo was pumping no oil into the air/exhaust at all though. It was a BW turbo.
But to be safe one could just do what garrett suggests then-use a scavenging pump with the cooler. It might take a little searching to find the right one, but I'm sure it can be done.
I'd like to know how the guys that have remote mounted turbos plumb in their drains. They sit quite low in relation to the block yet don't seem to have any issues that I have heard of and I would think there has to be some pooling going on.
But to put the knife in the heat issue altogether, as Hondarider suggested he wanted, the easiest fix is probably to route the drains into the upper oil pan as one normally would and install a secondary oil/air cooler in front of the stack and use one of the oil ports in the block to supply it with oil. Providing there is enough restriction in the aux cooler to still be able to maintain oil pressure in the engine it would work fine.
When I get my triples installed, I plan to do some testing of the back pressure in the oil drains, just out of curiousity sake and see how high I can take it before it starts leaking past a seal. I know Simon had well over 100psi going to his turbo's on the supply side before they started leaking and it had to be pressurizing the center section!! He had to install gauges and ball valves to control the flow to the turbo's till he got the issue sorted out!
So what would be the best solution to this problem? I c there are a lot of trucks with the same results as the original poster and would like to see how it can be fixed. I'm installing mpi twins and 45% over in a few weeks and u guys have me freaked out now.
I wouldn't be to worried until you start pulling a trailer and giving the truck a decent workout, if your going to do that get a oil cooler checkout Setrab and Mocal- http://www.batinc.net/mocal.htm .Mocal has some good high flowing thermastats and adaptors a little pricey but these engines flow alot more oil than the regular old gassers so there's probably not much to be found in Summit/Jegs thats going to flow enough. I think we need a good DIY oil cooler thread.
Thanks I will have to look into those u said to. All I know is it seems to be a common result no matter what twins are run and I'm nervous now. Goin to have to do something. Where would be the best port to put the sensor for the oil temp be? Gettin one of those for sure. Goin to look like a dam air plane dash now with all this stuff goin on. Oh well would be nice to know what's its running. Maybe I should pull the a-pillar gauges and the dash pod and buy the cts monitor for the guages.
Looked at the mocal oil cooler. Which one would be the one that would work best? Rows? Or style? Any pointers would be great. Thanks.
Some poeple have used the Setrab 920 cooler but I wouldn't with out getting some actual numbers from Setrab. Mocals units look the same as Setrab I bet Setrab makes them, look at Mocal mostly for the the thermal bypasses and sandwich adaptor. I noticed they have a new sandwich adaptor thats a high flow unit that you can get fitting sizes up to 16AN wich is pretty damn good, same with the thermal bypass. Maybe give them a call and see if they will give you flow specs for 5w40/15w40 through there units. I found a spec on oil pumps a while back for our trucks but forgot maybe someone else will post it.
I wonder if Socal has an oil cooler with a bypass of very cold weather starts so a thermostatic control can tolerate the greater outside air temps and supply the engine with the needed volume of oil. I would install an oil cooler if it helped an expensive engine endure cold/hot conditions with a large enough flow line. The fuel cooler discussion has many same issues and minimal temps printed to see a trend if cooler fuel and at what temps an optimal fuel operation range is also. You know Fleece could have an opinion too here with their temps up north maybe they'd chime up for a kit to use for both oil and fuel coolers each truck has it's mods so this would take some work to describe and experiment to get optimal temps from start to run and where to shut off so the turbo etc. gets cooling. This just sounds like a neat subject to work up and try to make a consistent running engine's fuel, oil, air temps.
Sourced some parts today started with a 11x8x1.5 B&M cooler, rated for 200psi. P?N 70266
I have a pretty big trans cooler so space was limited, but if you have a stock trans cooler, there is a 11x11x1.5 cooler too.
(4) 1/2" to -10AN adapters
(4) -10 to 1/2" pushloc adapters.
Im still debating if I want to use steel braded line or the regular pushloc hose, im not looking for a big change, but a 20* drop would be nice to have. I'll post up as I go along on having it on the truck. Id like ot get done with it in the next few weeks, but we will see :thumb: Planning on using the feed/return ports on the oil filter housing.
I have a pretty big trans cooler so space was limited, but if you have a stock trans cooler, there is a 11x11x1.5 cooler too.
(4) 1/2" to -10AN adapters
(4) -10 to 1/2" pushloc adapters.
Im still debating if I want to use steel braded line or the regular pushloc hose, im not looking for a big change, but a 20* drop would be nice to have. I'll post up as I go along on having it on the truck. Id like ot get done with it in the next few weeks, but we will see
:thumb: Planning on using the feed/return ports on the oil filter housing.
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Sourced some parts today started with a 11x8x1.5 B&M cooler, rated for 200psi. P?N 70266
I have a pretty big trans cooler so space was limited, but if you have a stock trans cooler, there is a 11x11x1.5 cooler too.
(4) 1/2" to -10AN adapters
(4) -10 to 1/2" pushloc adapters.
Im still debating if I want to use steel braded line or the regular pushloc hose, im not looking for a big change, but a 20* drop would be nice to have. I'll post up as I go along on having it on the truck. Id like ot get done with it in the next few weeks, but we will see
Cool. I'm interested to see your results.
