CAM POSITION SENSOR GEAR PLAY

[EDawson]

Hey brothers.. Checked 25 things off the to-do list and just finished the body bushings on a 40K mile ‘87GN I came home with the day after Christmas last year. Getting ready to tackle the rear main seal (leaking and stinking), timing chain (it’s time) water pump (I’ll already be in there) and valve springs (because everyone says so). Car has had a tick from the upper front drivers side from day one which I didn’t like and probably should have made me walk away from. Worse on cold start but quiets up some once warmed up. Sound is progressive with RPM. There’s a certain YouTube video with a very similar noise which didn’t really end with a diagnosis. Figured I will start with the easiest job and pull the valve covers and check for rocker arm damage or play before mortgaging my house to dig into worn cam lobes, stuck lifters, spun bearings, etc. I’m a weekend warrior not an engine builder and talked to RCG about dragging it up there for the work and a good tune. That didn’t go overly well so I’m on my own I guess. Anyway for shits and giggles I pulled the cam position sensor cap off and put a Phillips on the screw holding the brass cap and (1) noticed a good amount of back and forth play, (2) a knocking/ticking noise very similar to what I hear with the engine running (3) in a similar location to where I hear it. QUESTION IS.. how much play is normal between the cam sensor gear and the cam gear when not under load Just turning the screw back and forth? Thanks a ton

 

[Chuck Leeper]

Pull the sensor, and look at the base of the housing. There should be "bars" on the end. If those are worn down/off, there's too much end play.
Scot @GNS rebuilds them.

 

[earlbrown]

Just drive out the spring roll pin that holds the gear on the shaft. Get a small block chebby distributor shim kit and put the roll pin back.

Easy peasy.

 

[turbo nasty]

Just drive out the spring roll pin that holds the gear on the shaft. Get a small block chebby distributor shim kit and put the roll pin back.

Easy peasy.

This not good advice if you do not do what Chuck says to inspect. If the feet are worn away the sensor has no way for the internals to get the splash and mist oiling needed. AKAS teh shim will be flush with bottom of cam sensor body and no feet present. I can repair it if is that way but needs to be sent to me. Either way inspect it. Good Luck