Running terribly

[Sle-z_90]

So, I don’t know what cam is in my engine. I honestly don’t know what engine I have. I know the heads have the casting number 14102193, which says they are factory 5.7 heads. I know the truck came with a 5.7 from the factory. So, I assume it’s the original engine. Maybe the cam wasn’t changed. Prior owner said it was but I think the “lope” was probably because I have 3 bad cylinders, lol.

So when checking valve lash, should I just check a cylinder that has good compression and then use that to check the bad cylinders?

 

[PlayingWithTBI]

So when checking valve lash, should I just check a cylinder that has good compression and then use that to check the bad cylinders?

Check them all, just keep track of what you found.

 

[Sle-z_90]

Check them all, just keep track of what you found.

Thank you

 

[Erik the Awful]

193 heads are the stock TBI heads. They are widely regarded as one of the worst heads for power, but great for gas mileage. I have a pair on the original engine out of WCJr that I did some porting work on. Headbytes Porting has a good video series on how to clean them up.

 

[Schurkey]

when checking valve lash, should I just check a cylinder that has good compression and then use that to check the bad cylinders?

Doesn't work like that.

And you don't have "valve lash" with a hydraulic-lifter camshaft. You have "lifter preload".

Which is to say you take all the lash (clearance) out of the valve train, and then screw the adjuster nut another 1/4--1 turn, so that the lifter plunger is depressed some amount.

"Valve lash" is for solid-lifter cams, where there's some free-play in the system to assure that the valves will close with the engine frigid, cold, warm, hot, or over-heated.

 

[Sle-z_90]

Doesn't work like that.

And you don't have "valve lash" with a hydraulic-lifter camshaft. You have "lifter preload".

Which is to say you take all the lash (clearance) out of the valve train, and then screw the adjuster nut another 1/4--1 turn, so that the lifter plunger is depressed some amount.

"Valve lash" is for solid-lifter cams, where there's some free-play in the system to assure that the valves will close with the engine frigid, cold, warm, hot, or over-heated.

I’ve been processing this comment and, if I understand you correctly, if I go to check lash using the EOIC method detailed in that video, there should be none. I shouldn’t be able to fit any of the metal guages in there. If I can fit anything, that’s a problem?

 

[Schurkey]

I’ve been processing this comment and, if I understand you correctly, if I go to check lash using the EOIC method detailed in that video, there should be none. I shouldn’t be able to fit any of the metal guages in there. If I can fit anything, that’s a problem?

Yes, that'd be a problem. When it comes to hydraulic lifter lash, there should be LESS than "none". The valvetrain of a hydraulic-lifter engine has PRELOAD in nearly all cases, and the exceptions would be for aftermarket "high performance" parts.

Which is why you don't check "lash" on a typical hydraulic-lifter engine. There isn't any. You'd check "preload".

A typical hydraulic-lifter engine has all the "lash" removed (the adjustment taken to the "zero lash" point, and then tightened some more based on the lifters used; and the philosophy of the person doing the work. 1/2 turn of preload is common.

EOIC is rational for adjusting lash on a solid-lifter engine. It's a giant waste of time for hydraulic lifters. I'm not saying it won't work. I'm saying that there's easier, faster ways of doing it.

 

[Sle-z_90]

…8 months later

I finally got the preload set on my valves. In the process I did something stupid. I loosened my distributor and lost all track of where it should be. I heard somewhere that the #1 wire should be pointed at the #1 cylinder so I started with that. I then moved it back and forth and all I’m getting when I try to crank it over is a whine and a dull pop. Once I got fire. I uploaded a video of what it’s doing to YouTube. I would love some advice on whether this is likely the result of my distributor stupidity or something additional. The link is below.

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Also, when turning the engine over by hand, I noticed sometimes it’s somewhat difficult and occasionally it was super easy. I assume this means my cylinder compression issue wasn’t resolved by setting the proper preload. Would y’all agree?

 

[packer0440]

…8 months later

I finally got the preload set on my valves. In the process I did something stupid. I loosened my distributor and lost all track of where it should be. I heard somewhere that the #1 wire should be pointed at the #1 cylinder so I started with that. I then moved it back and forth and all I’m getting when I try to crank it over is a whine and a dull pop. Once I got fire. I uploaded a video of what it’s doing to YouTube. I would love some advice on whether this is likely the result of my distributor stupidity or something additional. The link is below.

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Also, when turning the engine over by hand, I noticed sometimes it’s somewhat difficult and occasionally it was super easy. I assume this means my cylinder compression issue wasn’t resolved by setting the proper preload. Would y’all agree?

For the distributor, (if going from scratch) the motor should be at TDC of the compression stroke, and the rotor should be pointed at the #1 wire on the cap (normally it roughly aligns with the #1 cylinder but not exactly). Based on your description you most likely have it 180 degrees (1 full turn of the crank) off.

Depending on what the valves are doing the engine may be easier or harder to turn at certain times. Only another compression test will tell if you’ve solved the issue

 

[Sle-z_90]

I think I found tdc on #1. Removed distributor cap and got it lined up with the whirler pointing at cylinder #1, then reapplied the cap ensuring that #1 plug wire was over the whirler. Idc, maybe I have to actually pull the whole distributor. I’m pretty sure I was on tdc compression because the exhaust and intake rockers were both up. My understanding is they’ll be down on tdc exhaust. I started it up and this time I got fire.

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