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I have developed the well documented leak at the sump gasket that looks like it is coming out of the oil filter. I was finally able to get the cleaned up and jumped my safeties so I could actually see it running. The drip is coming down from the sump but is getting blown on the back of the filter mounting plate, then dripping down. I've researched what I need to do to get the engine off and plan on replacing the gasket and the shaft seal. Most things I've read on this caution against replacing the split alignment pin and substitute an alignment pin that doesn't have the split. The gaskets seem to be packaged without this but with an o-ring. I have found a part number for the pin but some of the pictures seem to show a solid pin and some pics still show the split. Can anyone furnish a good Kohler part number for this pin without the split? TIA.

Jacks Small Engine is where I purchase most parts from.

What split alignment pin are you talking about?

Hope you don't mean the sump to crankcase gasket as there is none other than properly applied RTV.

Rivets said:

What split alignment pin are you talking about?

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This is just from what I have read: There are 2 locating pins between the sump and the case. One (or both) of these had a split in them when originally built which contributed to the blowouts on the sump gasket. Supposedly superseded by a pin that didn't have the split in it. I think this may be the number https://www.jackssmallengines.com/j...5hezwljftkh8nwc01ikpmreqttixnepyaaoo5ealw_wcb

StarTech said:

Hope you don't mean the sump to crankcase gasket as there is none other than properly applied RTV.

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This is the breakdown (I think) of my engine sump, showing a gasket. It is on a 17yo Dixie Chopper. https://www.partstree.com/models/cv...-20hp-14-9kw/oil-pan-lubrication-3-24-502-11/

To be honest with you I’ve never, ever replaced one of those pins, plus as Star said, no gasket just sealant. I don’t know where you are getting your info from, but I would seriously question the authors. Here is a service manual for your engine, I would follow its instructions. https://www.mymowerparts.com/pdf/Ko...d-CV17-CV18-CV20-CV22-CV25-CV22-CV23-CV26.pdf

17 years ago they may have used a gasket where specified by the equipment manufacturers, but technicIan’s have learned that sealant does a better job.

Rivets said:

17 years ago they may have used a gasket where specified by the equipment manufacturers, but technicIan’s have learned that sealant does a better job.

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Only on parts like sumps that are rarely removed
Parts like rocker covers that should come off every couple of years need gaskets .
I once got the crankies & charged the customer a full hour for removing all of the silicon from his intek twin rocker covers.
HE bitched about it then found out the B & S techs charge 2 hours to adjust the valve lash for exactly this reason.
Probably fit better than 100 intek rocker gaskets to engines that were originally glued on with silicon.

Bert, this guy has a Kohler, not Briggs, and I’m just passing on the service manual instructions. Most Kohers call for gaskets in all other areas, with a few exceptions. In this case Briggs is in a different ball field and I agree with you, no sealants. I have found that you can remove sealant from valve covers very quickly with a wire wheel, but I did ruin a few before I learned how to do it without heating the metal. Now it’s a 5 minute job.

This CV20 appears to be exception to the service manual instructions. Personally I have yet to see a CV20 with a pan gasket.

Yes Rivets you got to take it easy on the cleanup of the RTV. Many techs don't know how to remove the rocker covers without damaging them otherwise too.

FWIW the covers are easy cause they will sit in a pan full of old petrol which will soften the silicone enough for it to rub off.
It is the head that is the problem.
Easy if it is off cause you are doing a head gasket but a PIA if in the mower with frames , mufflers & brackets in the way.

I must gotten use to cleaning up the head rocker cover areas while the engines are mounted. No worst than those baked on / stuck on gaskets. I do ran into rocker cover screws that are seized on some Kohler twins that break off. Then it drilling them out and resizing to M7-1.00. Usually its the one right over the exhaust port.

Most times I use a backbone razor blade to do this work. Getting the surfaces oil free is a little time consuming as I know the RTV does stick/setup properly if the oil is allowed to touch the RTV before it fully cures.

The consensus seems to be for the sealant. If I take it apart and find that it was built with a gasket, am I going to run into trouble with clearances if I go back with sealant?

Also, I read the list of approved sealants in the shop manual furnished by StarTech. Some of these seem to be pricey and only available in relatively large quantities. Will the Loctite 587, 598, or ultra copper be sufficient?

Will carb cleaner be OK for the final cleaning prior to applying the Loctite?

Thank you all for sharing your knowledge!

Rivets: Thanks for furnishing the manual. My very next question was about bolt tightening sequence and torque!

My findings is that the thickness between sealant and a single gasket is too small to worry about.

Rivets said:

My findings is that the thickness between sealant and a single gasket is too small to worry about.

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Thanks, Rivets. Can you share which of the sealants you've had success with?

There are those who will disagree with me on what sealant to use, but I have found that the two I will recommend are probably the most expensive, but I know they work for me and I don’t have to worry about taking it apart a second time. To me the price of the sealant is cheaper than my labor if I use a cheaper one and have to redo it. I only use either Honda bond or Kubota bond sealants. Just my opinion and those who disagree with me can go to the back of the longest line of those who think I’m a crazy old fart.

Type of RTV sealant isn't as picky as following the directions for its use. The sealant Kohler supplies their dealers has a 1 minute set time. Hondabond is go stuff also and will work. I use what I have handy sometimes and depending on how big of a hurry I am to get it back to the customer. Some of those RTV sealants require 24-48 hour cure times.

I have used brake cleaner and rubbing alcohol to clean the surfaces prior to applying sealant. Most important thing is getting all the oil and grease residue off of the surfaces.

Ether is about as good as it gets when you're in a hurry to clean surfaces & use clear silicone as a gasket on 18 wheeler axles & hub caps.

I do what Ilengine said for cleaning, i've used Permatex Ultra Black, gas and oil resistant and and good for up to 500 degrees farenheit.
apply it, finger tighten all bolts, it usually dries around 1 hour, i then torque bolts to specification, and then let it sit for 24 hours for a full cure before adding oil

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I had a Kohler where the entire engine case came apart in two pieces, I remember thinking it was really weird setup compared to the Briggs V-twin. I believe it had alignment pins which lined up each side to it's opposite/matching side. Most mechanics I know have used the Red I believe it is the High Temp and Oil resistant sealant. He would put the sealant on put the sides together but not tightly leaving a small amount between sides. I think it was 30 min to 1 hr later he would tighten the parts. Someone else may have more info or it may have been covered already I did not read all the post. K

A Honda engine trainer suggested to install a sealant film that you could smell. These machined case's require very little sealant. Also suggested not to mess with the old sealant. Just apply new sealant . Assuming first sealant was correctly installed.

Permatex® Super “300” Form-A-Gasket ​

?

louky1150 said:

I have developed the well documented leak at the sump gasket that looks like it is coming out of the oil filter. I was finally able to get the cleaned up and jumped my safeties so I could actually see it running. The drip is coming down from the sump but is getting blown on the back of the filter mounting plate, then dripping down. I've researched what I need to do to get the engine off and plan on replacing the gasket and the shaft seal. Most things I've read on this caution against replacing the split alignment pin and substitute an alignment pin that doesn't have the split. The gaskets seem to be packaged without this but with an o-ring. I have found a part number for the pin but some of the pictures seem to show a solid pin and some pics still show the split. Can anyone furnish a good Kohler part number for this pin without the split? TIA.

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Try Kohler's website: www.kohlerpower.com

louky1150 said:

I have developed the well documented leak at the sump gasket that looks like it is coming out of the oil filter. I was finally able to get the cleaned up and jumped my safeties so I could actually see it running. The drip is coming down from the sump but is getting blown on the back of the filter mounting plate, then dripping down. I've researched what I need to do to get the engine off and plan on replacing the gasket and the shaft seal. Most things I've read on this caution against replacing the split alignment pin and substitute an alignment pin that doesn't have the split. The gaskets seem to be packaged without this but with an o-ring. I have found a part number for the pin but some of the pictures seem to show a solid pin and some pics still show the split. Can anyone furnish a good Kohler part number for this pin without the split? TIA.

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I have a 2005 Dixie Chopper with a Kohler 20S and that engine uses a gasket. Without the gasket there is no crankshaft end play and the engine will not turnover.

Rain today. said:

I have a 2005 Dixie Chopper with a Kohler 20S and that engine uses a gasket. Without the gasket there is no crankshaft end play and the engine will not turnover.

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That why we always need the complete engine numbers including spec (type) numbers not just the model number. Different specs have different setup at times. Many of the CV20 don't have oil pan gasket but a few do as we can now see with the spec number being provided.

As a follow up, I completed this job, using the gasket, day before yesterday. The old gasket was very brittle, and you could see where it was compromised around the locating pin near the oil filter. Started up with no issues and no leaks so far. It looks like Kohler has been changing things, probably trying to address this problem. I found reference on YT to a Kohler part number 24 041 54-S which was packaged with the gasket and a new, solid locating pin. This part number has been superseded by 24 041 66-S which is packaged with the gasket and an O-ring (and no locating pin). When I looked at the manual, it shows the rtv application pattern going around an O-ring, and also filling a "groove" between 2 points on the casting. My engine had no groove, and no seat for the O'ring. I asked the part dealer for a solid locating pin, but they didn't stock ANY of the locating pins. What pushed me over the edge to go back with the gasket was reading about all the color coded shims available to achieve proper clearances. I feared exactly what Rain today mentioned in his post above. Thanks so much for all the input from everyone.