75th motor problems

[krt]

So my dad's 75th stop running took to the shop that always took care of is. Got a call that one of the cylinders has bad compression. Oil didn't look bad . Didn't get a chance to talk to the mechanic who looked at it. Not sure what I should do next.

Edited July 10, 2022 by krt

[PhanDad]

If I remember correctly, your Dad's 75th still has the Triad engine; hopefully it's something minor and it's not a boat anchor.

Maybe @ShaunE can offer advice.  

 

[ShaunE]

I'd find out what the compression readings were first & I would verify myself & follow up with a leak down test.  Then see if the timing belt is still intact & on all of the cogs.  These are non-interference engines & if the timing belt broke or came off, you may have a valve open causing low or no compression in one or both cylinders.  If the belt is broke, I'd say you are lucky & replace.  If it came off the cogs then I would suspect a failed oil pump which unfortunately is not supported any longer for rebuild parts.  Download the Kohler TH service & parts manuals which will tell you how to install, time & torque the timing belt if that is the problem.  The engine will have to be removed for this.  If you do find out the engine is toast, there are a few repower options out there with only one being marginally inexpensive & that is using a Harbor Freight Predator Engine.  Many here have done this & documented the procedure.  I myself will opt for the Kohler Command repower & have already procured all the necessary parts to perform this.  If you really want to keep your 75th original, OPE Engines still have TH18 short blocks available for about 2K. 

 https://www.kohler-engine-parts.opeengines.com/short-blockslong-blocksmini-blocks-triad-th-ohc-c-781_93_162/kohler-part-2852204-th18-short-block-p-1485

You will have varying opinions on what route to take.  It all depends on how bad you want to keep this tractor & how far you are willing to go to keep it running & dependable. 

 

[PhanDad]

2 hours ago, ShaunE said:

Download the Kohler TH service & parts manuals...

Both are available in the "Downloads" forum.  

 

[krt]

Good news the shop Mast Lepley that my Dad did all his business with his tractors said they could install a newer Kohler engine with a change to the ignition switch some different heat shield and a muffler installed for around $3,500 .

[abu507]

Go buy a older cub 18hp command and out it in lots less money

[Wilbur643]

You can get a brand new Briggs & Stratton 18hp Vanguard engine kit from Small Engine Warehouse made to replace the TH18 Kohler in the Simplicity Sovereign for under $2000 shipped, it comes with everything you need plus instructions. It's pretty much a plug and play install if your good with wrenches, if not ask your dads guys if they would install it and how much to do it. It's a two to three hour job at the most, you should save at least $1000 dollars. It's been about a year and a half since last I checked with them, the price may have gone up some but I don't think it would of gone up $1000 dollars.

Edited July 13, 2022 by Wilbur643

[Justplaintim]

Ken if your going to get a new engine for the 75th I know someone that would want the old triad for parts.