Thanks for the 8.1 video! Looking forward to seeing the Yukon XL come to life. Maybe one of these days you'll use it to chase down some Corvette parts😁
I've been building Chevy Engines for 50+ years yet the 8.1 though similar in a lot of ways to the 454 is new to me. a) A discussion of Torque Specs for the Cam Gear and Timing Cover would have been nice; according to the GM Factory Repair Manual the Cam Bolts should be torqued to 22 FT LBS and the Timing Cover to 53 INCH LBS. There is no mention of using Loctite; personally, if the part is available to fit the 8.1 and there is enough of a recess within the Timing Gear, I would have used a Cam Tab Lock Plate which should be available just about anywhere. b) When doing the Timing Chain Replacement, I'm assuming most Mechanics or DIY Guys will be doing this job with the Engine still in the vehicle and the Oil Pan still bolted on. From what I can see, you have the pan off which should have resulted in this job being pretty easy. With the Oil Pan still on, I'm curious as to whether you need to drop the Pan about 1/2 an inch to clear the lip of the Timing Cover without disturbing the Pan Gasket. To drop the Oil Pan you need to find some room to do this - on a 2x4 vehicle it's pretty easy but with a 4x4, you have a choice of either lifting the Engine up an inch or dropping the Front Differential enough to clear, neither of which is a quick, simple task. c) Unless the Timing Cover Seal for the Harmonic Balancer is a newly revised part, should it not go in from the Front? It also appears using the block of wood and hammer technique the inner section of the seal was messed up - some mention as to the seal differences might have been a good idea.
Hey AG, good points. Thanks for adding to the discussion👍. Sounds like you have been around the BBC since almost the very beginning. You're correct in that this last generation MKVII series BBC still uses the lower timing cover to oil pan retaining lip, so the pan will need to be lowered in order to remove it. The timing cover crank seal is actually a revised item, and it came with a plastic installation tool without any instructions for proper orientation. As you mentioned, I was used to installing from the front, but the tool appeared to only work when installing from the backside, so I rolled with it. I guess if it leaks, I'll just pull it again. Thank goodness I like to work on these😁.
With 182K on my 8.1, while I'm doing a Water Pump and a Balancer, I'm thinking of doing the Timing Chain also. My question is do you have to drop the Oil Pan to get the Timing Cover off or will the Cover just lift up and over the edge of the Pan?
Yep, it will be necessary to drop the oil pan down just a bit to clear the lip of the timing chain cover. For my purposes, I removed the pan entirely, but you can get away with backing the oil pan bolts out to bring the pan down.
Hey Cheezy, you want to avoid trying to fit an early door before 1992 on a 96 car. The earlier doors will physically bolt to the car, but the internal design and mounting points for door/ window hardware are different making it very difficult to get everything to work correctly.
Love this video, But I have 1 question why thee hell a single roller? Why not a Cloyes TRUE Double Roller? Would have been a better performance and reliability standpoint tbh.
This engine had a double roller chain already from GM. Problem is this engine is a 2002 production, with a different timing cover, cam sensor, and gear to accommodate the different timing of the Marine engines. Since this is going into a stock build 2004 Yukon XL 2500 that won't be seeing severe duty or high RPM's, I elected to install the stock timing chain gearset that would fit underneath the 2004 timing chain cover and work with the later design cam sensor.
