Predator 212 Hemi Won't Idle After Valve Lash Adjustment

SquidBonez

Member
I recently installed a stage 2 kit in my Predator 212 Hemi. While I was testing it out, the valve lash adjustment screw on the exhaust rocker backed out and allowed the pushrod to fall out from beneath the rocker. No big deal, this happened once before and all I did was reset the lash and I was fine. Now, after setting the lash multiple times, I can not get the engine to idle. It will only start with starting fluid, idle for about 5 seconds, and then die. The pushrods aren't bent, and when I cycle the engine everything works as it should valvetrain wise. I picked up a new carb to see if that would fix it (last time I couldn't get my engine running I just swapped the carb and it fixed it...plus it's only $12). But if/when that doesn't work, what should I try? (EDIT: It didn't work.)

LIST OF MODS:
PVL Flywheel, 4 Degree Offset Timing Key, ARC Billet Rod, 22lb Valve Springs, 0.01” Head Gasket - $5 MOD2 Camshaft, Header Pipe, Muffler, 0.38 Carb Jet, Chromoly Pushrods 5.54”, Autolite 3910X Spark Plug
 
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SquidBonez

Member
Is the lash cap still there ?
You were in the carb ?
Yep, both lash caps are still there. Haven't looked at the carb yet, but considering I replaced it a few months back it should still be clean. Although the kart did sit for a little while before I installed the stage 2 kit. I know small engine carbs don't like sitting long. That's why I might just try swapping it again.
 

flattop1

Dawg 89
10mm wrench and the bowel is off . Wiggle the float check for fuel flow and debris in the bowel . Unscrew the idle screw pop the idle jet out check for a plug .
 

flattop1

Dawg 89
Even easier unscrew the drain see if fuel comes out .then the idle jet .
Spray the idle jet with a little goose grease and give it a twist or two before popping it out . Saves the o-rings .
 
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J par

Member
I'm not sure if this would apply but it's the first thing that came up in my mind when something like this happened to me with my car... I had a push rod jump up out of the center of the lifter and kind of pinned up on the side of the lifter a little bit so when things started running it dropped down in its place which made the lash extremely open and off to the point where it made a clatter...
 

SquidBonez

Member
Update: swapped the carb and I'm still having the same problem. It only runs when I rev it, and at that point it's trying to take off. If it helps, here's all the mods I have done. I did a compression test and the highest PSI I reached was 50 PSI. Keep in mind this is with a thin head gasket. I feel like that's low. Maybe when it threw the pushrod the piston smacked the valve? That's probably what I'm going to check next. Still want to hear some suggestions if you have them, though.

LIST OF MODS:
PVL Flywheel, 4 Degree Offset Timing Key, ARC Billet Rod, 22lb Valve Springs, 0.01” Head Gasket - $5 MOD2 Camshaft, Header Pipe, Muffler, 0.38 Carb Jet, Chromoly Pushrods 5.54”, Autolite 3910X Spark Plug
 
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tbyji2

Member
50 PSI seems too low, if your sure that is all the compression you are getting I would start there.

Also, what's air gap on coil? Double check timing key. Consider lapping flywheel in and setting timing that way, not as quick, but the taper "never" shears.
 

SquidBonez

Member
50 PSI seems too low, if your sure that is all the compression you are getting I would start there.

Also, what's air gap on coil? Double check timing key. Consider lapping flywheel in and setting timing that way, not as quick, but the taper "never" shears.
Coil gap is 0.03, maybe a tiny bit over. Timing key is definitely in correctly. I also made sure to lap the flywheel.
 

SquidBonez

Member
You have a .038 idle jet ?
No. This is the jet I'm talking about: https://www.google.com/amp/s/www.go...e-carburetor-drilled-main-jet-predator-212cc/

At this point I doubt it has anything to do with the carb, especially considering I just swapped it out. Feel like we're chasing our tails here. It was running just fine until the pushrod fell out, now it won't run. Compression is lower than I would expect as well. I'm thinking bent valve. Won't know until I get the head off this weekend.
 
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does the cam have compression release on it? Not sure if im right. but if testing compression with the pull start it will read a low compression but i could be wrong about that
 
does the cam have compression release on it? Not sure if im right. but if testing compression with the pull start it will read a low compression but i could be wrong about that
thats why no one is paying his low compression any mind. You have to use an electric starter to get a good reading. Leakdown will tell him if he has a bent valve or not.
 
thats why no one is paying his low compression any mind. You have to use an electric starter to get a good reading. Leakdown will tell him if he has a bent valve or not.
yes i understand that, but he keeps mentioning it so i figured I'd point that out so he could retest the right way since no one else mentioned it for him
 
I have a bored jet already. 0.38 jet from the stage 1 kit.
you have a .038 main jet, sounds big for what you've changed so far. All those changes require carb tuning unless the kit came with a carb as well. i don't see how a loose rocker adjuster equates to a bent valve its losing lift not gaining. It's possible i guess but seems more likely it could of beat the lobe up with all the lash
 
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