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Predator 212 Hemi Won't Idle After Valve Lash Adjustment

Did a little more tinkering on it today. Called a small engine repair shop and they reccomended I run premium fuel and open the exhaust valve lash to 0.05" instead of the stock 0.03". Still nothing. Double checked if I had spark and I do. The last things for me to check is if I got the timing right and to open up the engine and check inside. If it's not one of those things then I'm completley lost.

If this was just a simple stage 1 engine then I would cut my losses and just buy a new one and swap all the bolt-ons over. But I have invested too much time and FAR too much money to give up on it. If I can't figure it out I'll take it to a small repair shop and have them figure it out.
 
Lose the phone number of the repair shop who told you to run premium fuel. Complete hogwash. You have ran the idle adjustment screw all the way in? Did not see it in your description. Extra valve clearance is on the wrong path too. First determine if it really is a fuel problem. Is the spark plug wet or dry? Is it the right plug? Timing is at least near where it needs to be and the ignition timing is somewhere near 32 degrees? No head gasket problems? If its a motor that ran before you messed with it, concentrate on each and everything you did to make it unacceptable.
 
mike97760 said:
Lose the phone number of the repair shop who told you to run premium fuel. Complete hogwash. You have ran the idle adjustment screw all the way in? Did not see it in your description. Extra valve clearance is on the wrong path too. First determine if it really is a fuel problem. Is the spark plug wet or dry? Is it the right plug? Timing is at least near where it needs to be and the ignition timing is somewhere near 32 degrees? No head gasket problems? If its a motor that ran before you messed with it, concentrate on each and everything you did to make it unacceptable.
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Agree with that first sentence. He mentions the exhaust lifter sticking previously. It probably killed the cam and thats why the pushrod fell out.
 
If the lifter is sticking, is it possible the lifter is stuck in the open position and there is not enough spring pressure to close the valve and the lifter back on the cam lobe? Rotating the engine without the valve cover to see if the exhaust valve is closing all the way may help. Just my 2 cents.
 
thebigo said:
If the lifter is sticking, is it possible the lifter is stuck in the open position and there is not enough spring pressure to close the valve and the lifter back on the cam lobe? Rotating the engine without the valve cover to see if the exhaust valve is closing all the way may help. Just my 2 cents.
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Everything looks normal when I pull the engine over but I might as well open it up anyway.
 
Another update. I took off the side cover and found something interesting. When I took out the cam (which was undamaged), the intake lifter fell right out (as it's supposed to) but the exhaust lifer - the same one I had to tap down with a hammer before - was wedged into the block. I couldn't push it out with my finger. I had to take a flathead screwdriver and gently pry it out and it eventually dropped. This makes me think the exhaust lifter is sticking somehow. I already ordered new lifters just to be safe, but I can't actually find anything wrong with it. It's not bent or warped. The pushrods are straight. The holes in the block that the lifters go into seem clear (see below):
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I also noticed what appears to be some wear on the side of the crank, but this has been on the engine since the very first time I opened it. Not sure if it's anything to be concerned about:
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Anything I should do to keep the new lifters from sticking? Assembly lube maybe?
 
DynoDon said:
If you had a lifter sticking you wouldn’t have had any compression.
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I have no idea what else it could be then. Cam was totally fine - no damage. Pushrods aren't bent. Lifters themselves look good. Double checked my coil gap (set it to a little bit larger than 0.03" which I believe is close to stock. When I put it all back together I'm going to reset my lash to what it was before I called the engine repair shop. What else can I check?
 
I ask you to give me a call. The offer still stands 570-515-0379. If I don’t answer leave a message
 
I tried the lifters again since there seems to be nothing wrong with them (and the new ones won't be in until the 28th). They both fit the same. Even if I swap the intake lifter into the exhaust hole and vice versa. When you push them all the way up without the cam or pushrods in they kinda stick. Just put engine assembly lube on them and closed the engine back up. Last thing to check is my timing key. Already re-did my coil gap and set my lash back to stock.
 
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In the hemi motor they use a really weak stock rocker arm. I had one, ran great until it didnt. Pulled the valve cover and a pushrod had fallen out. Put it back in and readjusted lash, ran fine for a little while. It quit again. Pushrod had fallen out again. This time I actually inspected it, the crummy rocker arms were bending due to the poor design and the heavy springs I was running. Id bought the motor used but did get the builder sheet that came with it. Read it and there it was Do NOT use stock rockers with these springs!
 
mike97760 said:
In the hemi motor they use a really weak stock rocker arm. I had one, ran great until it didnt. Pulled the valve cover and a pushrod had fallen out. Put it back in and readjusted lash, ran fine for a little while. It quit again. Pushrod had fallen out again. This time I actually inspected it, the crummy rocker arms were bending due to the poor design and the heavy springs I was running. Id bought the motor used but did get the builder sheet that came with it. Read it and there it was Do NOT use stock rockers with these springs!
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Good to know. I replaced the stock rockers with OEM replacements already but if they bend I will upgrade them.
 
You can always slot a 1/4" rod . Wrap some emry around it and hone the lifter bore some for extra clearance .
And chamfer the lifter bore .
 
Have you figured out where the idle jet is located ? Sounds like the lifters are mushroomed out enough to drag , possibly done when you had to use a hammer on them . Did you check the crank end play ? Also I have read in some posts here in the past about crank/cam interference . Was there a lot of shavings in the oil when you drained it ? Giving Don a call is a wise idea , he has spent hours with these engines , and knows what he is talking about , as well as many others on here . Just 1 other question , are you using a top plate and pump , or stock tank ?
 
GClary said:
Have you figured out where the idle jet is located ? Sounds like the lifters are mushroomed out enough to drag , possibly done when you had to use a hammer on them . Did you check the crank end play ? Also I have read in some posts here in the past about crank/cam interference . Was there a lot of shavings in the oil when you drained it ? Giving Don a call is a wise idea , he has spent hours with these engines , and knows what he is talking about , as well as many others on here . Just 1 other question , are you using a top plate and pump , or stock tank ?
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Lifters are fine. I didn't have to beat on them, just a slight tap on the exhaust lifter. New ones just came in and they're identical. Crank play is just fine. Cam clearance is fine. Not a lot of shavings in the oil (not more than what was in it before, at least...very little). Also running a stock tank, no pump. Worked just fine before.
 
Did you check the timing key yet? Might be time you open up the carb and go through it (I know you switched them out), but it sounds like a fueling issue.

Could also swap out the coil, but doubt its an issue.
 
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