: Hydraulic valve-lash adjustor evaluation?

06-10-09, 03:42 PM
Im rebuilding a replacement motor for my 2000 DTS but I don't know how to tell if the hadraulic valve-lash adjustors are any good. My OEM GM manual says next to nothing about inspecting them. Anyone know how to check them (without just buying a new set)?

06-10-09, 03:51 PM
Your engine has roller cam followers. The hydraulic adjusters are static, do not bear on the cam surface, and will not need replacement. The roller followers themselves are a very long-life item. Just make sure that, if for some reason you disassemble the head(s), that every piece goes back in the same place whence it came.

06-10-09, 04:13 PM
Thankyou for the speedy reply! I was quite careful about reinstalling every spring, valve, keeper, etc in their original location after changing all the valve stem seals so I oughta be in great shape. HOWEVER, I missed the step about getting each component chrome-plated! How many horsepower will I forfeit by omitting this (now) obvious step? Seriously though-- thankyou very much!

06-10-09, 04:27 PM
Before you button up the cam covers, pour a fair amount of GM, Iskenderian, CompCam, or someone else's EOS/cam breakin fluid over everything, and down over the chains.

06-10-09, 05:04 PM
OK, will do. Also, after I get it unbolted from the engine stand and the flex-plate bolted back on, I was considering connecting the starter while its hanging from the hoist (with the spark plugs out) and cranking it over maybe 20-30 seconds at a time to check for oil-flow up into the heads before actually reinstalling the engine. Got an opinion on this, whether necessary or just good for piece of mind?

06-10-09, 06:38 PM
There's a way to connect a drill pump to the oil filter adapter cooler fittings (hope you have 'em.......) and pump oil through the engine. Sort of a jury-rig, but it works.

If you used some sort of EOS on the lower end, assuming that you replaced the main and rod bearings, (maybe not necessary), you should be OK by rolling the engine under the conditions stated until you get pressure on a mechanical gauge.

Jake, you reading this ?????

06-11-09, 12:31 AM
A good idea, and one i had not considered but i guess that's why I'm here asking for advice... Thanks once again for your help!

06-13-09, 03:13 AM
Prime the engine with at least half a gallon of engine oil.

I bought a cheap pump-up garden sprayer at harbor freight and attached brass fittings on the end and screwed the line directly to the oil cooler holes.
Pump it up and it pushes oil through the block. Works perfect and you will not have a dry start.

06-13-09, 03:37 PM
Yes Sub- just caught this thread. Exactly what Sub said with the EOS, and if you lubed all bearings well and cams/lifters, feel free to crank the engine with the starter to pump oil throughout everything. This is a good idea. Make sure you have adequate oil and that you don't run the starter too long. Definitely with the plugs out- this will be easier on the starter.

As well, the same thing can be done in-the-car, just for visual inspection purposes it's easier on the stand.

06-13-09, 04:05 PM
This engine requires NO additional lubricants other than engine oil :sneaky:

GM requires you to pump 2 quarts of oil though the engine by either installing an adapter in place of the oil filer or going directly into an oil feed passage. The most common way of going into the oil passage is to remove the Engine Oil Pressure Sensor.
GM has a hand pumping device to do this. I wore our out and use the oil out of the gun now with some special adapters.

I pull the drain plug and let the 2 quarts drain out. This helps with flush out any contaminants. Like the sealer off the factory head blots.

06-13-09, 04:48 PM
How does head bolt sealant get into the lubrication system ?

06-15-09, 02:19 PM
I think he means the sealant on the bottom of the head bolt cap - some of that is exposed to oil

06-16-09, 07:04 PM
I think he means the sealant on the bottom of the head bolt cap - some of that is exposed to oil


The washer on the head bolt has orange sealer on the bottom side of it and the head of the bolt has sealer on the bottom side of it. When you torque then down the sealer shreds off.
Some times long strings and other times a bunch of little pieces.

06-16-09, 07:41 PM
Sounds like another Northstar Band-Aid.

06-18-09, 05:20 PM
Mmmm - maybe it would be better if the sealant WASN'T there? Mmmm - let's see...if those places were NOT sealed, motor oil would seep down there. Eventually, the entire head bolt cavity on the block would be filled with oil. Now, when the HGs start to leak, the oil would perhaps form a barrier to the coolant, thereby helping to preserve the threads in the block. What do you guys think about that?