1999 VG33E Flywheel position question

[Capt.SK]

Hi,

New member, and longtime lurker.

I am in the midst of rear main seal, clutch, and oil pan R&R. It is all going back together now.

I removed the flywheel to replace the rear main and I had it resurfaced. Since this engine has a crank position sensor that reads the flywheel it would make sense to me that the flywheel would be indexed to the crank. There is no dowel on the flywheel or a place for it. there is also no arrow or timing mark that I can see. There is an extra hole next to the bolt holes on the crank but nothing corresponding on the flywheel.

I should have marked it when I removed it but I wasn't thinking about it. I need to have this correct if it needs to be indexed.

I have looked hard and I can't find any information on this.

 

Please help.

Thank you,

Capt.SK

 

 

 

[Slartibartfast]

 

I don't see anything in the service manual about indexing the flywheel to the crank. EC-198 of the '97 manual (I assume '99 is the same, you can download it from Nicoclub to check for yourself) says the crank sensor on the VG33 is not used for engine control, and exists only for the onboard diagnostic system's misfire detection. I assume it gives the computer a higher-resolution speed signal than the one the computer gets from the cam position sensor (more pulses per degree of crankshaft rotation), allowing the computer to spot slight dips in crank speed, which it can then match to which cylinder was supposed to be firing at the time. (The computer uses the camshaft position sensor in the distributor for its spark and fuel timing.) The troubleshooting section for the crank sensor's trouble code shows electrical checks and a visual inspection of the sensor, but says nothing about indexing. The EM section has a spec for allowable flywheel runout, and of course a torque spec for the flywheel bolts, but no information suggesting there's a correct orientation on the crankshaft.

 

TL;DR, near as I can tell, it doesn't matter which way it goes on.

The other thing I found regarding the flywheel is that the '97 manual says to replace it rather than resurface it. Naturally they don't give a reason. I checked the '95 manual to see if it was the same, and it doesn't mention resurfacing, but suggests "repairing" any "slight burns or discoloration" on the flywheel or pressure plate with emery paper. I'm not sure if Nissan had some engineering reason for this or just liked selling new flywheels rather than paying for machine work. I haven't done a clutch in one of these, but I have not heard of a resurfaced flywheel causing an issue. 

[Capt.SK]

Thank you very much Slartibartfast. So the crank position sensor does not actually detect crank position at all? but rather engine speed hmm. If that is the case it needs to be renamed. I am 55 with arthritis and cancer treatments . it was really hard for me to remove the transmission.

 

I tried to download the clutch section and I could not find torque specs for the flywheel or pressure plate. The closest I can find from other sources is 70ftlbs flywheel and 30ftlbs for the pressure plate.

 

Thanks again.

[Strato_54]

Here is the diagram and specs for the clutch and pressure plate (CL-11). The fly wheel is speced at 61-69 FT-LBS (EM-37)

 

Welcome to the forum!

 

Edited October 21, 2022 by Strato_54

[adamzan]

It doesn't need to be indexed, and the crank position sensor on the VG33E doesn't actually have anything to do with how the engine runs (yeah, I know lol). It is just there for diagnostics. Since it is a distributor-based system, it doesn't utilize it for engine timing.