Thread:

496 HO maintenance

Both of my engines are 2005 models, my question is: What is recommended maintenance on these for average use? Like when do the valve covers need removed for inspection? Do the rockers need adjusted? Life span until overhaul? Haven't had any major issues & neither engine uses much oil. Thanks

Originally Posted by JETDOC

Both of my engines are 2005 models, my question is: What is recommended maintenance on these for average use? Like when do the valve covers need removed for inspection? Do the rockers need adjusted? Life span until overhaul? Haven't had any major issues & neither engine uses much oil. Thanks

Recommended is every 25 hours. I run synthetic and had an oil analysis done a few times and they suggested 60-65 hours. 50 would be a good happy-medium if you run a good syn. I do the drive every 75 hours with TORCO syn. I switched the entire motor and drive over to synthetics and have picked up 150rpm WOT. I am knocking on the rev-limiter (5150rpm) with a 24P even on a hot day. I couldn't get that close to it before. I am almost ready for a 26P.

Also, I removed the turbulators from the exhaust. They restrict 7hp each motor.

Shouldn't need to remove the covers unless something goes wrong or you upgrade the valvetrain.

No adjustment available to the valvetrain, unless you upgrade.

My wife's '04 Yukon is at 98,000 miles and 4,000 hours (LS motor). Figure a boat motor works TWICE as hard as an SUV motor. So 2000 hours should be attainable. I would probably put valvesprings and rockers (upgrade to performance stuff) at 500-800 hours, depending on how hard you run them. If you had your ECMs scanned, you would see that 90% of the time, you are probably idling.

Good info beer, I did check my hours on the rinda last summer & was surprised that 90% of total hours are under 3500 rpm & about 60% at idle. Are the turbulators your talking about the plate in between the manifold & riser? Arent they supposed to prevent any water from getting in the manifold? I also run full synthetic in everything, even the lawnmower

Originally Posted by JETDOC

Good info beer, I did check my hours on the rinda last summer & was surprised that 90% of total hours are under 3500 rpm & about 60% at idle. Are the turbulators your talking about the plate in between the manifold & riser? Arent they supposed to prevent any water from getting in the manifold? I also run full synthetic in everything, even the lawnmower

Yes, that is their intention.....80% of the owners have pulled them and not one water-related exhaust problem.

Mine have been out for 300 hours.

Looks like a new project coming up. Will be ordering new gaskets for the hp improvement. Thanks for the info

Originally Posted by JETDOC

Looks like a new project coming up. Will be ordering new gaskets for the hp improvement. Thanks for the info

Ya don't need em. 30-minutes tops for both sides. Lift the elbow off, take out the sandwiched plate. Put BOTH gaskets back down, put elbow back on. Move to other side and repeat.