Question Regarding L98 Intake Gaskets
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Question Regarding L98 Intake Gaskets
I am in the process of replacing the intake gaskets on my stock 1989 L98 engine. I am reading the FSM under the Intake manifold installation and it states "The blocked openings in the gaskets are to be positioned at the front of the engine". The old gaskets had the rear water ports blocked off. The new replacement gaskets also have the rear ports blocked off. Is this an error in the factory service manual or is there something that I am not understanding properly? I would greatly appreciate any help on this! 
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From: WV
I am in the process of replacing the intake gaskets on my stock 1989 L98 engine. I am reading the FSM under the Intake manifold installation and it states "The blocked openings in the gaskets are to be positioned at the front of the engine". The old gaskets had the rear water ports blocked off. The new replacement gaskets also have the rear ports blocked off. Is this an error in the factory service manual or is there something that I am not understanding properly? I would greatly appreciate any help on this!
Last edited by WW7; Dec 26, 2014 at 02:36 PM.
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My 89 FSM had the same mistake in it, I couldn't believe I had to correct the Factorys manual for them...Yes, put the restrictors in the back where they belong...I wonder if anyone ever ruined their motors because of this stupid mistake..If you use the FSM much expect to find a few more mistakes, I did....WW
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From: WV
...WW
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I'm currently getting ready to put a drain plug into my differential. I checked the FSM and it has generic maintenance info in that section. It says to replace the differential oil every 7500 miles or 7500 miles if operated under "severe duty" conditions and refer to owners manual. The owners manual says to replace every 100,000 miles.
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The intake manifold torque specs are completely weird in my '86 FSM. It says 25 - 45 ft-lbs, which I assume means torque to 25 ft-lbs first and then 45 ft-lbs. In the back of the section the torque is listed as 35 ft-lbs. I found a source online that said it should be 25, 45, 60. The torque sequence is missing a bunch of numbers. It does say to put the restricted water passages in the gasket in the rear.
I'm currently getting ready to put a drain plug into my differential. I checked the FSM and it has generic maintenance info in that section. It says to replace the differential oil every 7500 miles or 7500 miles if operated under "severe duty" conditions and refer to owners manual. The owners manual says to replace every 100,000 miles.
I'm currently getting ready to put a drain plug into my differential. I checked the FSM and it has generic maintenance info in that section. It says to replace the differential oil every 7500 miles or 7500 miles if operated under "severe duty" conditions and refer to owners manual. The owners manual says to replace every 100,000 miles.
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From: Anaheim CA
Check this out -- directly from the FSM:
As you can see, the top illustration of the torque sequence is missing a bunch of numbers on the bolt heads. There is no explanation of what "snug tightening sequence" or "tightening sequence" is or what is different about them. They must be different because the numbers on the bolt heads are different. The installation procedure just says "Reverse removal procedure", so that's no help.
As you can see, the top illustration of the torque sequence is missing a bunch of numbers on the bolt heads. There is no explanation of what "snug tightening sequence" or "tightening sequence" is or what is different about them. They must be different because the numbers on the bolt heads are different. The installation procedure just says "Reverse removal procedure", so that's no help.