Remove And Install The Chevy LT1 350 Crank Hub And Pulley

Supplies you will need:

– SBC damper puller
– 5/8 Socket
– Ratchet
– Torque Wrench
– Breaker Bar
– Spare Bolt and Washer
Removing the LT1 Crankshaft Hub

For a manual transmission, the only thing required to do is put the car in 5th gear and pull the e-brake. If you have an automatic transmission you need to keep the engine from turning. I chained up the crank hub to the frame but their are several ways of doing this. Using a breaker bar and 5/8 socket, loosen and remove the crank bolt and remove the chain.

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Rotate the engine until these arrows are lined up. This will help with reassembly.

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Find a spare bolt or rod that is smaller in diameter yet longer in length than the crank bolt. Also find a washer that will fit inside the crank hub. I will measure these later and post the correct sizes. Grind off the threads to prevent damage to the crank threads.

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Insert the junk bolt into the crank and then washer. The washer will keep the puller aligned on the junk bolt. It’s best to use a junk bolt that has a cup shape on top.

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Install the damper puller onto the hub and begin tightening. It might take some torque but the hub will pop and start to slide off.

SBC damper puller in action.

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Here is a quick animation I made:

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Here is what it looks like with the crank hub off.

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Installing the LT1 Crankshaft Hub

First thing you need to do is turn the motor over till the #1 piston is at TDC (Top Dead Center). I just installed the crank bolt and manually turned it.

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The cam dowel pin should be on the left.

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Clean and polish the end of the crank hub. If there is rust or dirt on the end it could damage the crankshaft hub seal. Ad a film of oil on the polished area before installation.

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It is recommended that you use a tool to install the hub. You can build a cheap one using these directions: http://members.cox.net/gmarengo/Misc/Misc.htm You can also just tap the crankshaft hub onto the crankshaft but you risk damaging your thrust bearing. With the arrow pointing straight up, line up the hub with the line on the timing cover. Use your install tool or a piece of wood to tap it on so you don’t mushroom the hub. Some people like to heat up the hub before installation.

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Once you’ve installed the hub, chain up the crank hub and tighten it till you reach 65ft lbs.

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Remove the chain and you are finished. Rotate the engine over one full cycle and verify that the mark it still lined up correctly.