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Hey guys,

So I have a '99 Grand Prix with the 3800 Series II in it, it had been leaking coolant in a few areas last summer, and got driven without hardly any coolant and blew a head gasket.
So $500 and a few weeks of new experiences later I had the heads resurfaced, all new gaskets in, new radiator and coolant lines and had it all back together.
Filled it up with oil and tussled with some vacuum lines and got it running! But it had a pretty irritating ticking going on coming from the far valve cover.
So I thought it was just oil taking a while making its way up, and I let it idle for 10-15 min and it continued.
I looked in the oil cap and I couldn't see any oil moving or squirting around anywhere out of the lifter rods or the rockers.
So I then wondered if it was having some oil pressure issues, I picked up a manual pressure tester kit and checked the pressure at the sender and it seemed perfectly fine; 40psi at the start and down to 20 after it got up to temp.
So then I was wondering if it got some coolant in the oil passages when the head blew and maybe ate away at the bearings making the knock, so I changed the oil and looked for little glittery bits of metal but didn't see any.

Now I'm at a loss, did I block some oil passages when I did the head gasket?
Im considering pulling it all apart again and looking under the valve covers closer, but I wanted some insight :dontknow: :)

Thanks guys! Sorry for the book!
 

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I hope you changed the oil after replacing the head gaskets. Washing out the bearings can definitely happen. If so, low oil pressure is expected.

20 psi oil pressure seems low. I would think 30 psi is the more the norm.

Low oil pressure will likely cause ticking from the lifters.

Be interesting to try using a heavier weight oil to check for improvement.

I ran some pretty heavy oil in our 3800 van with a main bearing knock for quite some time. Added Lucas stabilizer as well. An old van on its last legs...cheers,
 

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lifter preload procedure:

To check for lifter preload or lifter squish you need to first get to zero lash. Turn the engine over so that one valve on a cylinder is open. Because one is open, you know the other is closed, meaning the lifter is sitting on the base circle. With that lifter on the base circle loosen the rocker bolt and then retighten with one hand while spinning the pushrod with the other. This way you can tell when everything first makes contact (the valve is touching the rocker tip, the pushrod is touching the rocker & and lifter and the lifter is touching the cam). At this point of first contact you are at zero lash. Everything past this point is lifter preload. Continue to tighten the rocker bolt until the bolt hits its snug point. This is how much lifter preload you have. Each 1/2 turn of the rocker bolt is ~.050 of lifter preload. Your goal is to have between 1/2 turn and 1.5 turns if you have stock lifters or 3/8 turn to 1/2 turn if you have Comp lifters. As you can see the stockers have a lot more room for error.
If you have too much preload and you have exhausted the adjustment of the lifter, the valves will stay open and the car will not start due to lack of compression. If you have too little preload, the valve train will be noisy and you risk exploding a lifter and having a very costly repair.
Remember, once the engine is heated up things change a bit. Parts grow and you will have to calculate in ~.005 pushrod growth. Also each pushrod with vary +/- .005 making things critical in high performance applications.
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