Compression release and valves are correct, but compression too high?

Mattdad1 said:
After help here with a head gasket diagnosis, I replace the gasket and adjusted the valves, but compression is so high. The engine will barely turn over unless I cover the intake. Pulled the crank case cover, and the camshaft and compression release is intact. I figured I made a mistake adjusting the valves, so after reassembly adjusted them again and compression is still far too high. I’m stumped. Any advice.? Thanks in advance.
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Must be the compression release cam or bearing worn or bent. Make sure the valve actually raises b4 top dead center when turned slowly by hand.
 
Saw this post due to my current situation and hope to find some answers. I have a cousin whose craftsman T210 started having starting issues. I brought it home and started to diagnose it. Everything pointed to bad ACR but the main thing that made me think of that was when you'd turn over the engine and it would stop at the compression stroke. Mower battery was bad (12v when key off then dropped to 6v when key was on, engine off) so I used my battery off my zero turn and it would turn over but eventually get weak ( i assume due to how long it was cranking) and stop at the compression stroke. Saw some YouTube videos that said if you have a bad ACR, cover the intake port and that will get you by, so I did that and the mower turned over fine and started. So since I work for a shop, I took the engine with me and tore it apart to verify the issue, but I did adjust the valves to make sure I wasn't forgetting anything. After removing closure plate (bucket engine) I removed the ACR and everything was fine. ACR moved freely and spring was still there. My cousin's husband did mention that when he tried to use the mower last time, he saw sparks come from the starter or in that area and when I had the engine on the mower, turning it over sounds like crap, like something was holding it back from turning it over smoothly. Engine model is KS40-3011, serial number 4904909253.
I still have the engine apart but am going to put it back together soon.
 
What is your question?
AND
You will get more replies if you will start your own post.

Just some general info you might consider:
From what you have indicated it appears that you need to put the engine back together, set the valve lash correctly and then when cranking do not crank over 5 sec's or the starter is going to smoke. Those starters are intermittent duty. Crank 5 seconds and then let it rest for awhile to cool down.
Then test with a known good battery. If you use a know good larger automotive type battery of 300CCA or more and it still cranks weak contact dbelectric and price a replacement starter or take your starter apart and check or bench check the running amps. You can finds lots of you tube info about Kohler starters.
It also appears that the engine is not starting correctly or fast so you may have additional issues when you get it cranking good.

Make sure the engine is not hydrolocking due to Raw gas on top of piston.
 
Forest#2 said:
What is your question?
AND
You will get more replies if you will start your own post.

Just some general info you might consider:
From what you have indicated it appears that you need to put the engine back together, set the valve lash correctly and then when cranking do not crank over 5 sec's or the starter is going to smoke. Those starters are intermittent duty. Crank 5 seconds and then let it rest for awhile to cool down.
Then test with a known good battery. If you use a know good larger automotive type battery of 300CCA or more and it still cranks weak contact dbelectric and price a replacement starter or take your starter apart and check or bench check the running amps. You can finds lots of you tube info about Kohler starters.
It also appears that the engine is not starting correctly or fast so you may have additional issues when you get it cranking good.

Make sure the engine is not hydrolocking due to Raw gas on top of piston.
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Sorry for the confusion and I saw this post and had the same issues going on so that is the reason I posted on this post. The question I have is the same as the original post, I have too much compression and after adjusting valves, I still have the same result. The battery I used from my zero turn runs 345 CCA and the battery that was originally on the mower runs less than 250 (don't have an exact number but it's less than 300 CCA). So, as I was under the assumption that the ACR was bad, I tore down the engine but the found ACR to be fine. I did check before teardown if engine would spin without spark plug in cylinder and it did. Thats when I blocked air going to the intake and started right up. Also, when the battery begins to get weak, you can eventually hear the solenoid start to whine or could be the starter. I guess the next thing to check would be electrical besides making sure valves are properly adjusted. I also did not see raw fuel in the cylinder so I doubt its locking up since I did get it to start.
 
I understand your why for post:
I was indicating you will get more tips and opinions about your Kohler if you do your own post. I'm not real familiar with that engine for hands on experience, just giving basics.
If you find a bad starter and need a replacement you might check with dbelectric.com to compare replacement prices. Some Kohler OEM replacements are costly.
I've had good luck with their replacement starters. Let them tell you which one you need.
Also on the Kohler starters you can usually get a brush repair kit that is easy to install, but make sure the bushings are ok first, especially the upper bushing. If it has any side slack the starter will drag.
You can find You tube videos about re-building Kohler starters.
Appears you need to do a open up for inspection of the starter before ordering a new one. I take a file or a sharp awl and put a witness mark on each end of things so as when re-assembling things you have alignment witness marks for more user friendly alignment of the bolts and end plates.
I have electrical testers that go to 400 amps DC that I use to help confirm testing of starter amps.
Some guys are lucky enough to have a old style starter/alternator re-build shop close by and they just take their starters to them for testing and repair.

Also make sure you are adjusting the valve lash PROPERLY per the SERVICE manual for that Model engine.

The previous guy had one of them wimpy/weak Briggs engines that can be a pain. (but his just needed a very close valve lash setting, sometimes has to be little bit below minimum specs on those type engines due to cam/valve train wear)

At least your engine is a better made Kohler.
 
StarTech said:
It just easier to adjust the rocker when the opposite rocker is fully the valve. Also the intake valve is the one closest to the oil pan.
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This is the poorest way to adjust valves on any engine and shows a total lack of knowledge of engine design and operation. It assumes the Intake & Exhaust cam lobes are 180° apart, when in fact they are only about 90° apart.

6i9PIcul.jpg


This means when one valve is fully open, the other valve is already on the approach to being opened. IOW, not at maximum slack as is required for valve adjustment.
 
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They called it back in the day checking valve clearance on the heel of the cam. Making sure the valve you are looking at was on the back side or heel of the camshaft.
 
Whom ever, so many jumping in here. If you really have excessive compression, pull a head or two. Check for excessive carbon buildup on the head and behind the valves. Again this maintenance item is in EVERY engine manual just like some clean cooling fins. If a small chunk of carbon breaks off and gets into the cylinder bore, it will gouge the snot out of the bore. Carbon is some tough stuff. Look for de-carbonizing the cylinders in your engine manual. Usually like every 5-8 years??. More often if she drinks a little oil.

Also if your cyl head is packed with carbon, that carbon insulates the head and attenuates proper cooling.
 
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