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Discussion Starter · #1 ·
Thought this would go good in Go faster because of the "boost requirments" for the new motor.

So I am replacing the front main seal on my motor (GTE). I have attatched pics of everything near that location. Now the oil seal itself was perfect, but I am replacing it just in case. Now I have a bit of oil residue around the right side of the oil pump. Now from the pictures, should I pull everything apart and check it/replace, or does it look fine to clean up and reinstall everything?

On MKIV.com and SF it says that with major boost you need to replace the Front main seal due to a lot of crankcase pressure. I have to motor out and I am going to replace it anyway for "better safe than sorry" . I also have gotten Permatex Ultra Grey RTV Silocone to go with it.

Pics are big to show detail.















 

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I left both my RMS and FMS alone as they looked fine (at the time). My RMS went out about 100miles in...and had to take out the tranny to replace it. BIG PITA. My FMS is holding just great.

Did you bend the retaining bolt here?
 

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Good luck bro, the seal is notorious for shooting right out after replacement. IMO, you are safer with the old seal. If it aint broke, dont fix it.
 
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I would replace it while you are in there. And that oil leak could be from a numerous areas.

1.The FMS blows out on GTE motors due to the lack of oil relief on the lower portion of the oil pump. Thats why shops like PHR started to bore them out for more oil flow and relief of oil pressure.
2.High crankcase pressure also is attributed to the FMS blowing out.
3.Old FMS also cracks and break.
4.FMS bust as well as the RMS if you have worn out thrust bearings as well as a stiff pressure plate. A hardcore single disc high clamp load pressure plate also leads to thrust movement, crankwalk and FMS breaking.
 
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Discussion Starter · #5 ·
Yeah teck , I bent it a little. I fixed it though so no worries. Thanks for the response. I will end up just cleaning everything and replacing the FMS and RMS.
 

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FYI - When putting on the TT oil pump you may see a problem with an oil leak at the FMS. That is VERY common. You have to fix it by tuning your oil pump so it will put out the correct amount of OIL pressure. Otherwise you will leak oil from your FMS for life!
 

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Discussion Starter · #7 ·
OK well its an aristo engine, not that it matters GTE wise, but I am not going to mess with the oil pump then, I just wanted some outside knowledge.
 

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FYI - When putting on the TT oil pump you may see a problem with an oil leak at the FMS. That is VERY common. You have to fix it by tuning your oil pump so it will put out the correct amount of OIL pressure. Otherwise you will leak oil from your FMS for life!
fix it by tuning? boring out the pump>? I have someone running a TT oil pump with no leaks at all and no FMS blowout. you have to just seat the FMS/RMS seals flush with the surface and even all around.
 

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fix it by tuning? boring out the pump>? I have someone running a TT oil pump with no leaks at all and no FMS blowout. you have to just seat the FMS/RMS seals flush with the surface and even all around.
I fixed mine by drilling out a bit of the rear FMS Oil passage/drain, there is a problem with a lot of the new tt pumps in that the drain is blocked with cast iron chunks. There are many hundreds of people who have experienced problems with the FMS blowing out or just leaking due to this reason. I am not talking about porting the oil pump out as that does not solve the original problem. Of course there are other reasons you could be leaking, like crank pressure, bad install, etc..
 

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fix it by tuning? boring out the pump>? I have someone running a TT oil pump with no leaks at all and no FMS blowout. you have to just seat the FMS/RMS seals flush with the surface and even all around.
Once in awhile you will hear of a guy who gets a nicely sealed unit, but majority will tell you that after a replacement it tend to leak or blow out. There have been talk on SupraForums and Clubna-t about it and how to solve it.

Most will drill and tap along the lip of the seal flange on the pump and place three screws to hold the seal in place. It's known to work....
 

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Good info. guys because theres a hundred threads on this issue @ supraforums. Its a fact that front seal replacement is an issue hand in hand w/ the GTE oil pump. I'm still torn on what approach to take - "if it aint broke, dont fix it" or go the extra mile by drilling the pump/drain "better safe then sorry"
 

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Once in awhile you will hear of a guy who gets a nicely sealed unit, but majority will tell you that after a replacement it tend to leak or blow out. There have been talk on SupraForums and Clubna-t about it and how to solve it.

Most will drill and tap along the lip of the seal flange on the pump and place three screws to hold the seal in place. It's known to work....
Is this a problem at a certain HP level? If have done two of these in the last year and neither one has leaked. I run GTE pump and did nothing special other than correct install.

Stop trying to jinks me!
 

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Is this a problem at a certain HP level? If have done two of these in the last year and neither one has leaked. I run GTE pump and did nothing special other than correct install.

Stop trying to jinks me!
Honestly, I am not sure as I didn't pay much attention to that while reading about it. I believe the main problem was the retainer spring it wasn't holding the pressure too well. Some guys have tried the double spring method, some work and some failed. The known fix is to drill the pump and place screwed to hold retain the unit.

Mike it's not a bad idea to replace it but take the precautionary steps to prevent the seal from breaking loose. You have either the choice of drilling the drain and place screws to secure them or spend a few hundred on a SP Performance premodified pump. You choose, but they both seem to work.
 
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