97 K1500 Z71 Head Gaskets

Hello Gentlemen!

Just bought a 1997 chevy K1500 4x4 z71 extended cab with around 200k miles on it for $1200.00. Problem is it needs head gaskets.

I am not new to the 350, in fact, I have replaced head gaskets on one in a 1993 K1500 in the past. Thing is the farthest I've been into the newer 350's is the UIM off to replace the fuel pressure regulator.

I was hoping you guys would have some tips or pointers on anything I should also change while I'm there or what I should watch out for.

I have fel-pro severe duty head gasket set, and replacement fel-pro head bolts. I also have purchased a new heater hose quick connector for the back of the LIM, a new t-stat, and exhaust manifold packing.

I have a timing light for the distributer when I get it back together (which reminds me, how do I time it? Unplug what wire, and 0 degress BTDC?)

Anything else I should consider? Thank you guys!

Also should I use silicone on the new head bolts before I put them in? Do they go into a water jacket?

Should I use loc-tite on the LIM and UIM bolts?

Lots of great tips for intake manifold removal and installation in the "Tahoe" section of this forum. The timing light is next to useless on these engines, as timing is controlled by the engine computer. Carefully mark the distributor body position in relation to the intake manifold and the rotor position in relation to the distributor body. DO NOT ROTATE THE ENGINE AFTER YOU MARK THE DISTRIBUTOR! This should get the timing close enough to allow the engine to start, but final timing must be adjusted using a good, real time SCANNER (not a code reader-eraser) and adjusting the cam offset to 0 degrees +- 2 degrees @ 2000 RPM. Silicone on the bolts is a good idea, and won't hurt if not needed. I've always found that Loctite degrades quickly with heat, so I believe using it does no good.

Thank You!

False Alarm though. I did a compression test on the 350. Came back with all good numbers. While removing the spark plugs I found one that was shot. So I replaced them all. Now the miss fire seems gone.

I also was able to find that the steam was actually from a cracked heater core, so I now need directions on how to remove it. It doesnt look too bad. For the time being I have it bypassed and the motor holds water!

Biggest and wost problem is that I think it has a bad connecting rod bearing. I can hear a slight knock that seems deep. When I rev it, the knock seems to go away untill I let the RPM's drop, and it comes right back. The oil pressure guage is dancing around which to me could also indicate a bad rod bearing. So I think I will plastiguage all the conn rod bearings and replace as necessicary. Anyone know the easiest way to remove the oil pan?

Hey guys, one more question, How do I diagnose a missfire on the 97 vortech 350? How can I do a cylinder drop test with no tech 2?

A rod bearing knock can be diagnosed by pulling the plug wires one at a time,when you remove the load it quiets down. A main will pretty much stay noisey.

Thank you!

Update, #3 cylinder is not firing. When I did a compression check, That cylinder had less compression than the rest, and I also found the tip of the plug was damaged.

I think something might have fell in the motor.

Does anyone know if any small block 350 will bolt up to my trans, torque converter, accessories, sensors, and heads? Or is there a specific year range I need to get?

You have a L31 Engine with Vortec heads. GM Performance Parts sells a long block (see http://www.summitracing.com/parts/NAL-12530283?part=NAL-12530283&autoview=sku).

//2000CAYukon

Thank You!

Do you guys go anywhere specific for replacement used parts? 2000 is a little steep to spend on a truck with 250,000 miles on it.

I think I'll just try and find a used one. Problem is all the local salvage yards I have around here don't have any 350's.

Pull that head off and take a look. It's a whole lot easier to do than pull an engine. Is there any indication of coolant in the oil? These engines are known for intake issues like all other GM products that have OEM plastic intake gaskets, so you could have a bent con rod if that cylinder hydrolocked due to coolant intrusion.