9 replies to this topic

[Pollack Pete]

I started working on my C-161 today.It has a 16 horse Kohler engine.It turns over very slowly.Not even fast enough to start.Battery is fully charged.Starter is good.Anyone here know anything about the automatic compression release?Can it be fixed without tearing the engine apart?Thanks in advance for any and all help.

[KC9KAS]

Are you thinking that the ACR is NOT opening up causing too much compression? I think it holds the exhaust valve open a little until the engine gets to about 600 RPM, then closes...not sure on the 600 RPM.

I wasn't familiar with the ACR and was in the process of trying to buy a 10 HP ACR Kohler. The seller didn't know anything about the ACR either. I was turning the engine by hand and commented that it didn't have any compression. The guy said "OK" and then dropped the price to something I could live with. Got the engine home and saw the ACR sticker on the shroud. I read up on the ACR then went to the garage and fired it right up.

[bowtiebutler956]

I would make sure everything else is perfect before assuming it is the ACR but if it is you have to tear the motor completely apart, as it is attached to the camshaft. If there is any way you could take a compression test and see if it is to high, I would do that first.

[Anglo Traction]

If your thinking along the lines of KC9KAS's assumption, then you can try turning the engine over with the Spark Plug out first.

KC9KAS.....Your right on the Money with your understanding of the ACR .

Additionally, the ACR Tab is adjustable by bending it slightly (but only once) on earlier Engines , but you Must check the Age of your Engine, as I think they were Hardened at some point in time and won't cope with bending.

A Service Manual will be your best freind from this point on.

[can whlvr]

im not totally sure but you may be able to pop the head off and take a peek,or feeler gauge and check the valve to see if its slightly open,but as mentioned make sure your starter,and wires are good,maybe run a direct positive to the starter from a known good source,like your car or one of the hundred other tractors you have ,just kidding but i would try this before opening anything up,and if its the acr,you will have to tear her down pretty far

[rmaynard]

The ACR is a part of the cam. There are very fine springs that hold little arms in place until the engine reaches 300 RPM. If the springs fail, the ACR is deactivated, meaning that the engine will be under full compression all the time, and hard to start. The only way to repair the ACR is to remove the cam.

[WH854]

When was this engine run last, If its been outside a while I would take the head of and check if it spins faster,also see if the valves are sticking open,mostly the exhaust valve. This was the case on my K341 it was staying open. Also it takes a strong battery to turn a 16hp over in warm weather.
Chas

[pfrederi]

If you pull the head just watch the exhaust valve as you turn the engine over. It will pop up slightly on the compression stroke

[Pollack Pete]

WH854, on 22 February 2012 - 07:24 PM, said:

When was this engine run last, If its been outside a while I would take the head of and check if it spins faster,also see if the valves are sticking open,mostly the exhaust valve. This was the case on my K341 it was staying open. Also it takes a strong battery to turn a 16hp over in warm weather.
Chas

It ran this past fall.I mowed my lawn with it the last couple times.I'll check some of the things others have mentioned.Thanks for all the help,everyone.

[bowtiebutler956]

When you figure something out, let us know what you find.