|
RX-7 2nd Gen Specific (1986-92) RX-7 1986-92 Discussion including performance modifications and technical support sections. |
![]() |
|
Thread Tools | Display Modes |
![]() |
#1 |
less roof, more turbo...
Join Date: Jun 2008
Location: Stevens Point, WI
Posts: 25
Rep Power: 0 ![]() |
Please help diagnose coolant & oil pooling on LIM
87 TII motor, 100psi on each rotor. All emissions/ MOP removed. Full TB Mod. Here we are on the drivers side looking toward the primary fuel rail (1st pic). There is a pool of coolant that forms between the LIM and the block by the front iron (2nd pic). There is also a pool of oil between the LIM and the block by the rear iron (3rd pic)
|
![]() |
![]() |
![]() |
#2 |
less roof, more turbo...
Join Date: Jun 2008
Location: Stevens Point, WI
Posts: 25
Rep Power: 0 ![]() |
I am least concerned about the coolant. I will double check the nipples on the water pump housing and the rear iron where I blocked coolant flow to the emissions & throttle body about 2 years/ 4000 miles ago. If this isn't the source, I will check the hard line running over to feed the turbo. If these aren't my problem areas, is it the LIM-to-motor gasket or o-rings causing the puddle?
The oil stupifies me. There is no oil running over the top of the block since my oil injectors are removed and blocked off. The other thing is that the secondary runners have a oily residue and black color to them, while the primaries are clean enough to serve dinner on. Everything is clean in front of the throttle body. When looking through the throttle plates, the upper half of the manifold chamber is clean. The lower chamber looks oily inside. Pic at bottom shows the difference in the runners. If it matters, I used to have a catch can hooked up to the nipple closest to the oil filler cap. It was filling up rapidly recently with what appeared to be a lot of coolant and a little oil. I since just ran a hose from this nipple out the bottom of the engine bay with no catch can. Please let me know if you have any ideas. |
![]() |
![]() |
![]() |
#3 |
Big Daddy
Join Date: Feb 2008
Location: Rhode Island
Posts: 419
Rep Power: 18 ![]() |
That same thing happened to me when I swapped to my RB turbo-back exhaust. Turned out I had inadvertently loosed a bolt on the block. Tighten everything around there, see if that cures your problem.
__________________
Hell hath no fury like a rotor blown. |
![]() |
![]() |
![]() |
#4 |
My minds tellin' me no...
Join Date: Feb 2008
Location: Murfreesboro, TN
Posts: 4,043
Rep Power: 22 ![]() |
The coolant leak is probably as you suspect, one of the block off nipples leaking. The oil, I have no idea. I thought it would be an injector, but since you aren't running any.....who knows. Clean everything, put die in the oil, break out the UV light and see what happens.
__________________
1976 Mazda Cosmo RX-5 1976 Mazda Cosmo RX-5 2003 Toyota Tundra TRD 2015 Toyota 4Runner SR5 |
![]() |
![]() |
![]() |
#5 |
less roof, more turbo...
Join Date: Jun 2008
Location: Stevens Point, WI
Posts: 25
Rep Power: 0 ![]() |
I am going back to make sure the LIM to engine bolts are tight. Since both vacuum nipples mentioned previoulsy were fine, it seems it has to be from this area. This still doesn't explain the oil though...
|
![]() |
![]() |
![]() |
#6 |
My minds tellin' me no...
Join Date: Feb 2008
Location: Murfreesboro, TN
Posts: 4,043
Rep Power: 22 ![]() |
Take off the LIM and replace the gasket.
__________________
1976 Mazda Cosmo RX-5 1976 Mazda Cosmo RX-5 2003 Toyota Tundra TRD 2015 Toyota 4Runner SR5 |
![]() |
![]() |
![]() |
#7 |
Rotary Fan in Training
Join Date: Feb 2008
Location: Pittsburgh
Posts: 81
Rep Power: 18 ![]() |
I had coolant leaking from the housing to LIM passage last year. Turns out I had bad o rings. I have since put freeze plugs in them and tapped the rear iron coolant feed to the turbo.
|
![]() |
![]() |
![]() |
#8 |
less roof, more turbo...
Join Date: Jun 2008
Location: Stevens Point, WI
Posts: 25
Rep Power: 0 ![]() |
Mystery more or less solved. The bolts on the LIM were still tight, so I pulled the LIM and the exhaust manifold off. The LIM-to-engine gasket was still in decent shape. However, both of the coolant o-rings had split in half. This still doesn't really tell me why there was oil pooling on there, but oh well...
Since I've gone this far, it looks like I will be blocking the rear iron and manifold coolant ports. I figure if I just put on a turbo that doesn't need coolant fed to it, there is no more chance of coolant leaks.... ![]() |
![]() |
![]() |
![]() |
#9 |
Rotary Fanatic
Join Date: Apr 2008
Location: Louisville, KY
Posts: 302
Rep Power: 18 ![]() |
i dont think there is a dowel pin oring in that area so i have no idea whats going on with the oil
__________________
My car blows up everytime I start it, it's rotary ![]() ![]() |
![]() |
![]() |
![]() |
Bookmarks |
|
|