QuestionQUESTION: I just rebuilt my kohler 23 horse ch23. model 76536. the question I have is that after running a short time and I shut down the engine I hear a gurgling sound. I suspect its the new oil pump I put in. There is a slight negative pressure in the crankcase. the compression is good around 125-130 per cylander. no blue smoke, engine is running a little rich at the moment.I am still in the process of breaking in the engine. the pressure is reducing slowly as the rings seat . got any clues as to the gurgling and the negative pressure? The negative pressure is such that at first I suspected it was blow by but when I put my thumb on the oil filler tube it stops and doesnt try to push my thumb away, ever so slightly holds my thumb there. I am going to change the air filter tommorrow to see it that allows more air to enter the carb. the old filter is really dead. Thanks for the reading
ANSWER: Hello Steve:
You can View a Breakdown of the Engine at this Site Addy; http://www.kohlerplus.com/login.asp and Select Enter as Guest. Now Select the Thumbnail of the Engine Catalog you Wish to View. Select the Command Twin CH/CV 17-26 CH/CV 620-750 Thumbnail. Now Enter the Spec #76536 in the Search Box at the Top Right of the Page. Now Select the Service Manual #TP-2428-C . It is Possible the Gurgling Sound is the Oil Draining Back into the Crankcase or it can be the Oil Pump Flushing Back into the Crankcase. If the Engine is Not Running Hot and Boiling the Oil and if there is No Banging, Tapping, Knocking or a Down Right Pesky Ticking, then I Suggest you Operate the Engine for a While and See if the Gurgling goes Away. Save the Service Manual I Directed you to on your PC and/or a Backup USB Storage Drive. The Manuals that Kohler Offers is Free (1 per Household) and they are the Same as the Ones I have in Paperback in the Shop. Is there Pressure in the Crankcase when the Engine is Running. Be Careful when Checking the Pressure if you Do Not have the Set Up to Properly Do this. You can Use a Face Shield (Not Safety Glasses) and this will Protect you from Possible Oil that May Fly Our when you Remove the Oil Fill Tube while the Engine is Running to Check for Crankcase Pressure. Lay your Hand/Thumb Over the Oil Fill and See if you Feel ANY Pressure Against your Hand/Thumb. If you Hit a Snag or this Does Not Correct the Problem, I am Here if You Require More Assistance. Hope this Helps. Let me Know What Happens, Please. Have a Happy Holiday Season and May the All Mighty Bless You and Yours. Be Safe and Happy. Thanks.
Good Luck
Respectfully
John
PS: I am Allowed to Answer 10 Questions a Day. If you See I am Maxxed Out, then Try Submitting your Question at or Just After 8pm EST (US). My New Day Starts then. Comments and Ratings are Greatly Appreciated. Thanks.
Respectfully
John
---------- FOLLOW-UP ----------
QUESTION: Hi John, I do have a followup question for you. After checking out the gurgling sound I noticed a tapping sound on the number two cylender . I think it is a malfunctioning tappet. It seemed to always be too soft at the top of the compression stroke, so much so that I had a .035 gap. As there is no adjustments, I took it out and bled it down reinstalled and it continued to tap. I then took it out and took it apart and added some oil inside of the tappet in the spring area. Apparently it failed to hold the internal compression and bled itself off. Is it possible to replace just one tappet or should I get complete set. Also is negative crankcase pressure dangerous for the machine, or is it something I can live with. Its not a lot as I said before it sounded like blowby originally but when I put my hand on the oil filler tube it didn't push my thumb away,instead slightly held it there, not a suction as such just a slight negative pressure. Thanks again for the reading, Happy New Year. Steve
AnswerHi Again Steve:
>>I Researched this Engine and Found that it is Designed to Run and Operate a Vacuum Operated Fuel Pump on Some Equipment it is Used on. It is a "Slightly" Negative Pressure. You Described it Almost as the Kohler Technician did when we Discussed it.
>>I Always Replace Both Hydraulic Lifters at the Same Time Never 1 at a Time. You have Just as Much Wear and Tear on 1 as the Other.
>>Please, Do Not Hesitate, If you Hit a Snag or this Does Not Correct the Problem, I am Here if You Require More Assistance. Hope this Helps. Let me Know What Happens, Please. May the All Mighty Bless You and Yours. Thanks.
Good Luck
Respectfully
John
>>PS: I am Allowed to Answer 10 Questions a Day. If you See I am Maxxed Out, then Try Submitting your Question at or Just After 8pm EST (US). My New Day Starts then. Comments and Ratings are Greatly Appreciated. Thanks.
Respectfully
John
Hi Steve:
>>I Just Read your Post and had a Few Moments to Say Thanks for the Ratings and the Comments. Thank you for Using All Experts Also. Till Next Time. May All Your Mechanical Problems be SMALL ONES and May the All Mighty Bless You and Yours. Thanks Again.
Best Wishes and Good Luck
Respectfully
John
