Kohler KT745 7000 series V twin slow/no crank

[lee]

Kohler KT745 with 390 hours barely turns over due to high compression. Pulled plugs turns over fine. Checked valve clearance and one ex valve was a little loose. The rest of the valves were already at .004. So I adjusted the one valve to .004 and then measured compression. One side was 190 psi and the other 185! No wonder this engine doesn't want to turn over. Once u get it to turn over it starts and runs fine. Questions: How do I fix the high cranking compression? New camshaft? Is this a known problem with this engine?

[KE4AVB]

Lee,

Need spec to double check but the couple specs that I looked at uses the 32 010 07-S camshaft and images of it doesn't show an ACR. With this in mind and the fact I had to replace several non solenoid shift starters for dragging under compression load due to top bushing wear and shaft wear. So I would try a new starter if it was in my shop.

[bgsengine]

Im with KE4 , although I would first do a relative starter draw test for future comparison with a new starter.. First check the starter draw amps under load, then check with no load, (and/or a bench test as well) and with those 2 or 3 amp readings noted down somewhere, do the same 2 (or 3) tests on the new starter and note the results.. Also, do a voltage drop test on both power and ground sides because you may have a resistance somewhere such that it passes just enough amps to crank normally with no load, but can't pass enough amps to crank under load.. (we've posted voltage drop test procedures a few times in these forums, BTW)

[bluemower]

I don't know if this is the correct manual for your engine as there may be a different manual for your spec.

service manual for 7000 series KT-745 (have to copy & paste)
http://www.kohlerengines.com/engines/on ... 03_ENA.pdf


The following is listed on page 18 of the service manual.

COMPRESSION TEST
For Command Twins:
A compression test is best performed on a warm engine. Clean any dirt or debris away from base of spark plug(s)
before removing them. Be sure choke is off, and throttle is wide open during test. Compression should be at least
160 psi and should not vary more than 15% between cylinders.
All other models:
These engines are equipped with an automatic compression release (ACR) mechanism. It is difficult to obtain an
accurate compression reading because of ACR mechanism. As an alternative, use cylinder leakdown test described
below.

[KE4AVB]

You have to take what is written in the service manual with a grain of salt sometimes. This why I researched the camshaft for images of it to be sure if it had an ACR or not which the PN I posted clearly shows it doesn't which makes the info for the Command twins valid.