350 Uneven Cranking & Won't Stay Running After Break In

[HQM383]

So I just went out to the garage to check a couple things. Distributor cap, rotor, and coil all look/tested fine. I was rotating the engine by hand to make sure the distributor was lined up properly, and I noticed something...

I was cranking it over by hand with the distributor cap and the valve covers off, watching the rotor and the rockers. I had all the spark plugs in. It was (of course) a bit more difficult to turn. I was able to hear the air hiss as I rotated the crank - building compression I assume? Sounded like it was in the crankcase. Then I got to a point in the rotation where the engine turned much more easily, and I heard no air. I kept rotating it around, same thing happened every time right around the same spot - near the #3 firing position when looking at the rotor. I then observed the #5 rockers at this time - exhaust opened, closed, then intake open and closed during this area of "easier rotation." What's interesting is that the rockers that loosened up for #3, #6, and #5. All of which are in succession in the 18436572 firing order. I wonder what could have happened that affected all 3, one after the other.

Anyway, if the air/hiss sound is in fact just compression being built while I turn the engine, there is definitely an area where compression isn't being built. I guess I'll confirm with the testers when I get them.

That disconfirmed my wacky distributor theory. The cranking vid sounded as though it could have been some cylinders barely trying to fire but it’s the opposite and the starter is having an easy time with some cylinders. Did you do PTV check with the build? I think someone mentioned bent valves earlier. This would have a huge impact on compression and slightly reduce valve spring height that could be the answer to the loose rockers. From what you described above it’s heads off.

[BillK]

I think I would pull the filter off and cut it open. You might find your answer. If its full of metal then you need to stop and tear it apart.

[evilws666]

I think I would pull the filter off and cut it open. You might find your answer. If its full of metal then you need to stop and tear it apart.

Welp, here's the oil filter. I pulled back each fold to see/feel what was in there. I also ran a magnet through. I did find a small bit of metal particulate in some of the folds, but it didn't seem like much. Most of what you see in the photo is the filter element I believe. Definitely not like the filter from the last cam that I wiped. That thing was nearly black.













Some oil on my finger. You can see some small metal particles:









What do you guys think?

[BobbyB]

I am not an expert here. I see you asked for help and no one answered you yet.
I say call mike Jones and talk to him about what you have experienced.
I still believe all your problems are likely from misadjusted valves. I still suggest the Ellison video methods.
Nice car! Hopefully you will soon have a nice engine working in it.
Good luck!

[Hrdlx62]

Doesn't really appear to be catastrophic cam meltdown. What lifters? Lifter Quality is pretty hit and miss these days, Lots of miss . I've seen new lifters stick in the collapsed position. Most shops around here are disassembling new lifters and cleaning and relubing them before use. Check your valve adjustment, I've never used the "Ellison " method but am going to try it on the next build I do. Good luck and yes that is a nice car hope you get it rockin!

[Ishiftem]

Is it possible the engine ingested something? Since the idle wouldn’t come down and when it did by pushing the throttle closed, you heard the clank and it shut off?

[evilws666]

Well I'll be damned! Bobby's post got me thinking about the valves again.. So i just went out there, loosened each nut 1/4 turn, and cranked it for a few seconds. No more gallop! I guess it was hanging a valve(s) open. I loosened them all up quite a bit just to make sure they weren't still pumped up, even though it's been sitting. I'm gonna go back out in a bit and try the method shown in "Ellison's" video and see what that gets me. If that doesn't work, I might try locking them down at zero lash and see what it does.

I am not an expert here. I see you asked for help and no one answered you yet.
I say call mike Jones and talk to him about what you have experienced.
I still believe all your problems are likely from misadjusted valves. I still suggest the Ellison video methods.
Nice car! Hopefully you will soon have a nice engine working in it.
Good luck!

It may turn out that you were correct sir! Thank you for the compliment. I had it on a DIY rotisserie made form engine stands a couple years ago. Did a frame off. Grinded/sanded/blasted everything and painted/powder coated anything that went back on. The rest of the body will be somewhere down the line. Haven't gotten to drive the damn thing since!

Doesn't really appear to be catastrophic cam meltdown. What lifters? Lifter Quality is pretty hit and miss these days, Lots of miss . I've seen new lifters stick in the collapsed position. Most shops around here are disassembling new lifters and cleaning and relubing them before use. Check your valve adjustment, I've never used the "Ellison " method but am going to try it on the next build I do. Good luck and yes that is a nice car hope you get it rockin!

They are Johnson lifters. Mike from Jones Cam's made sure I got the good ones. Let's hope it's just the valve adjustment at this point. I'm going to try the Ellison method, I'll let you know how it goes. Thanks for the compliment!

Is it possible the engine ingested something? Since the idle wouldn’t come down and when it did by pushing the throttle closed, you heard the clank and it shut off?

I highly doubt it. I didn't have anything anywhere near the carb, or anything on the carb loose. The clack I heard was definitely the rockers that loosened up.

[Tom Walker]

Your cam lift caught my attention as an old rule of thumb for stock vortec heads was .470 lift as max.

[evilws666]

SHE'S ALIVE!

I did the Ellison valve adjustment method. It was pretty simple to do, don't have to keep track of your positioning and whatnot. Once they were all at zero lash, I gave it 3/4 turn like he recommended.

NOPE! Too much. I'd say it was worse than before! So I backed them each up 3/4 turn and got them back to roughly zero lash. Pumped the gas a couple times, hit the ignition, and she started right up. They're definitely still on the loose side, as they are noisy. It's interesting - I gave them 1/2 turn on the engine stand (with no oil in lifters) and that was good for break in, minus the few that got loose on me. Then I did 1/4 turn, and that was still hanging a valve open. The Ellison method above with 3/4 turn was obviously too much, and zero lash is of course too little. 1/8 turn maybe?! Weird.

I think my best bet might be to cut up one of these old vortec valve covers and just adjust them while it's running. Either that or I'll have to keep trying different amounts of preload and see what it does.

I'm pretty sure I found the reason for it idling high as well. I sprayed some carb cleaner around my carb gasket, and the idle dropped. I reused the gasket, which I've had success with before, but I guess it's time for a new one.

Next up is getting the valves adjusted right so I can at least move the car and run it without worrying. Then I can dial in the timing and see if I can get the double pumper running happily. Then I'll take it for a quick drive to make sure the rings seal up, then change out the break in oil. After that I'll have to start thinking about the heads. All the comments about the lift has me a bit worried.. I definitely beat the piss out of this car.

Just wanted to again thank everyone for thinking this one out with me. I appreciate you guys a bunch.

[Tom68]

If you had them that tight you should still be checking for bent valves.

Check out Weingartners video on bent valves that still seal.

[HQM383]

Something is still odd that the hydraulic lifters won’t take preload. From your description it’s like the lifters are pumped all the way up solid. Violates the principle of hydraulic lifters. However you adjusted the valves before first start up seemed to work so your methodology must have been ok. Maybe they all pumped up solid beyond preload during that run in period and that’s where they are stuck?

Lifter brand?

[evilws666]

If you had them that tight you should still be checking for bent valves.

Check out Weingartners video on bent valves that still seal.

Ok, I'll take a look. Thank you.

Something is still odd that the hydraulic lifters won’t take preload. From your description it’s like the lifters are pumped all the way up solid. Violates the principle of hydraulic lifters. However you adjusted the valves before first start up seemed to work so your methodology must have been ok. Maybe they all pumped up solid beyond preload during that run in period and that’s where they are stuck?

Lifter brand?

They're just standard Johnson lifters.

Yeah, I was actually sitting here thinking about it after I walked away from the car. It's great that it's running, but something still doesn't seem right. It's like I'm adjusting solid lifters like you said.

You know.. going back to the break in, remember how I said I tried pulling the throttle blade closed a little, it rattled, and then I found 3 intake valves loose (3, 6, and 5). What if something did in fact cause them to pump up solid beyond preload like you said, and that's why those rockers were loose after that? Hm.

Another thing that's odd is that when I was out there before, I loosened each rocker arm and then went back inside for an hour or so, in case they needed to bleed off. While I was adjusting them, I tried pushing down on the rocker tip above the pushrod to see if I could feel the "squish" of the lifter cup depressing, but I didn't feel anything. Granted, I don't know how much they actually travel - is it only something like .070" that would be hard to feel?

I just got off the phone with Mike from Jones Cams.. he's stumped as well. We discussed how maybe the oils inside the lifter somehow got gunked up during the 9 months that they sat in my basement.. but then again they broke in just fine, and my initial 1/2 turn adjustment worked just fine too. We talked over a few other scenarios, just thinking out loud, and nothing really made sense. Only thing we were really left with was to pull a lifter and inspect it. Obviously I'd prefer to not pull my intake and do those gaskets again..

Should I be able to feel the squish of the pushrod depressing into the lifter cup after the car has been sitting for a little?

You know.. now that I'm thinking about it.. I went out real quick the other night to put a straight edge across the studs. Since I have poly locks, I couldn't actually go across the top of the studs exactly (that probably still translates though, if a stud pulls higher, I assume the nut would as well). I noticed that one of the poly lock nuts looked LOWER than the others, as if I had to tighten it down further to adjust that valve. If I remember correctly, that was the #5 intake valve - one of the one's that loosened up. Would that be a sign of a collapsed lifter? I'll have to go out and look again. Maybe compare the pushrod heights or find a way to measure it.

[novafornow]

Probably would not feel any give. Also, If it actually started at 3/4 turn, how long did it run. It will take maybe ten seconds to smooth out. If it was actually holding all the valves open, how did it even start?

[evilws666]

Probably would not feel any give. Also, If it actually started at 3/4 turn, how long did it run. It will take maybe ten seconds to smooth out. If it was actually holding all the valves open, how did it even start?

The 3/4 turn adjustment that I gave it today made the "no start" condition worse. While cranking, the "gallop" was even more evident - it didn't start.

[HQM383]

FWIW if at first assembly you went 3/4 turn after zero lash and the lifters pumped up fully then around.031” multiplied by rocker ratio was added to valve lift at all points.