Intermittent lifter tapping ?

**2NDSLPSS** · 08-29-2011, 08:18 AM

Since I put the cam in for about 5minutes every day or every other day I get a really loud lifter tap. Then it goes away just as fast as it comes. Usually when its been driven for a few.

Already pulled valve covers and checked rocker arm tqs. Everything was solid. It went a little overdue on the oil change and I assumed that was it but it has had a fresh 10w30 mobil1 oil change for 2 weeks and still doin it. Lifter failing?

**1slowbusa** · 08-29-2011, 10:28 AM

Does it do it when you do a cold start (Piston Slap) or also when the car is warmed up and you start(what size push rods, Did you check the length you needed with an adjustable pushrod?) post a video.

**2NDSLPSS** · 08-29-2011, 01:01 PM

Its def not the good old ls1 piston slap. It sounds like its just a single lifter. Usually its when I have been driving it for 20-30 min and its good and warm. Sometimes it starts tapping while the car is idling, sometimes when im cruising down the road. Then just goes away a few min later. No check engine light no nothing.

**2NDSLPSS** · 08-29-2011, 01:05 PM

Its the standard size pushrods for this cam TSP 233/239 113 7.400 chromoly pushrods. If it would be the pushrod size or a bent one im thinking it would be nonstop vs the come and go noise I get.

**1slowbusa** · 08-29-2011, 01:59 PM

Did you replace the Oil Pump? I have read that if the oil pump is replace and the o-ring for the pickup tube is not installed correctly you can get noises. The way to check is pull the dipstick out and look for air bubbles on the dip stick after its been running a bit.

I dont know if this would work but next time it does it make sure its in your drive way and pull the valve covers off and see if you have play in the rockers to the push rods. What side does it sound like its coming from.

I have also read someone had an issue with the power steering pully and it was making a sound that sounded like a bent pushrod.

Just things to check.

**1slowbusa** · 08-29-2011, 02:02 PM

See if you can post a video.

**transamtom** · 08-29-2011, 04:55 PM

Maybe you set the lash too tight when you installed the rockers?

**2NDSLPSS** · 08-29-2011, 07:29 PM

Yes i replaced the oil pump with the tsp ported ls6 pump but have checked the oil a few times when hot and once running and the oil looks good.

I put a screwdriver on each valvecover and used it as stethoscope and cant remember wich side i heard it louder from but it was definitly not coming from an accessory. Def valvetrain.

Maybe i fudged something cause the rockers are stock and i thought i was good with putting them on and TQing them and moving the valvetrain and rechecking the tq. . . . Is adjusting lash something u do on non adj rockers????

**transamtom** · 08-30-2011, 03:36 AM

Originally Posted by 2NDSLPSS

Yes i replaced the oil pump with the tsp ported ls6 pump but have checked the oil a few times when hot and once running and the oil looks good.

I put a screwdriver on each valvecover and used it as stethoscope and cant remember wich side i heard it louder from but it was definitly not coming from an accessory. Def valvetrain.

Maybe i fudged something cause the rockers are stock and i thought i was good with putting them on and TQing them and moving the valvetrain and rechecking the tq. . . . Is adjusting lash something u do on non adj rockers????

Well I guess its not lash but you need to follow the sequence:

The tighten and turn method gets you close real close but if you over tighten the lifter won't pump up and that could be what your hearing.

The TQ spec is 22ft lbs and you need to rotate the engine.

With the engine at TDC #1 tighten 1,3,4,5 on the intake side and 1,2,7,8 on the exhaust side.

Now rotate the engine 360* and tighten 2,6,7,8 on the int. and 3,4,5,6 on the exh.