k-90 x4

[jsp_333 273]

As we all know it never rains it pours.  After searching diligently for over a year I was rewarded on the weekend with
with 3 k-90's for my rj project.  The tractor itself is in pretty good shaped - it's just getting a good cleaning. 
The engine is another story. Didn't realize how much was missing off it until I picked up these three "parts" engines.
Tonight I was going to start taking them apart.  Any thing to look out for?  Any reason not to take them apart.
P.O's said all would work with a part here and a tinker there but I'm only looking to get my k-90 working and any parts left over
I'll make available here

John

[WHX?? 49,483]

I'm sure some other members  here have  specs & a manual for a k90/91 so hopefully they will chime in. That would be a good place to start.

[slammer302 2,155]

I usually take the head off and if everything looks good I take the oil pan off and give it a good cleaning and try it out if your going for show quality I would disseminate and redo everything

Sent from my XT1080 using Tapatalk

[Coadster32 793]

It's been a while, and I could be mistaken, but I think the oil pans are different from k90 to k91. I think the k91 became a common bolt pattern with other smaller Kohler blocks.

As to weather or not to disassemble them all, I wouldn't. They are all matched parts now, meaning they have all worn evenly, or unevenly, together. Also don't see the need take them all apart if you only really need one parts engine. Maybe if the first one doesn't have what you need, do the second. They'd be worth more together than apart, especially if they are just missing one or two parts each here or there.  Good luck either way.

[jsp_333 273]

Thanks Coadster hadn't considered the wear factor - you're right.
As for whether they're worth more as working engines or not I'm not so sure I
want to put time into getting them up and running.
Really just want to get the rj on the road.
Guess I'll start with least likely candidate to ever be a functional engine.
 

[MikesRJ 552]

Take the best of the four and start there. I'd pop the heads off and see which has the least wear as far down as can be measured without dis-assembling further. Once you identify the best block, build that engine.

[jsp_333 273]

For me this comes down to what will make the tractor most valuable if I ever decide to sell it.
I think I'd rather do a little extra work to get the original engine functional on the assumption it will pay off in the long term.
The point of rounding up all these engines  (it was a 9 hour odyssey) was to get the original engine running.
If I'm wrong please let me know because I'm pretty sure I can have one of them running within the week.
PO said all it needed was push rod to the points and I installed that tonight.

John
 

[MikesRJ 552]

That depends entirely if the original engine bought with the tractor is in fact the original engine. There's little way to tell other than the serial number being in the same date range as the tractor (actually it should be a bit before the tractor, but you get the idea). Other than that, you pretty much should go with the original if original, or go with the best engine you can, in order to maintain value. It's being restored. Then restore it to the best condition you can to get the most value out of it. To give you an example, my RJ didn't have an engine when I found it, but the RJ did have a serial number. I spent the better part of 5 months locating an engine with the correct serial number to place its manufacture date a bit before that of the tractor. It make not be the original engine to the tractor, but it certainly is the "right" engine to be on the tractor, right down to its model and date of manufacture. (I did eventually put a Schnake recoil and the correct carb bowl on the engine, but at this stage of the restore I was starting with the rope.)

Edited September 2, 2015 by MikesRJ

[jsp_333 273]

Where would I find the serial numbers for tractor and engine.
The engine that came with tractor had no shrouds so obviously no kohler plate on flywheel shroud

[jsp_333 273]

Can anyone recommend reading for "small engine rebuilding 101".
Don't want to bother everyone with every little question because I have never done this before
and I'm thinking it might be an idea to do a little research first.
Thanks

John

[oldredrider 2,553]

Download the Kohler engine service manual. EVERYTHING you need to know is in it. Download 2 copies. One for the
"library" and the other for the garage.

[RedRanger 1,468]

That depends entirely if the original engine bought with the tractor is in fact the original engine. There's little way to tell other than the serial number being in the same date range as the tractor (actually it should be a bit before the tractor, but you get the idea). Other than that, you pretty much should go with the original if original, or go with the best engine you can, in order to maintain value. It's being restored. Then restore it to the best condition you can to get the most value out of it. To give you an example, my RJ didn't have an engine when I found it, but the RJ did have a serial number. I spent the better part of 5 months locating an engine with the correct serial number to place its manufacture date a bit before that of the tractor. It make not be the original engine to the tractor, but it certainly is the "right" engine to be on the tractor, right down to its model and date of manufacture. (I did eventually put a Schnake recoil and the correct carb bowl on the engine, but at this stage of the restore I was starting with the rope.)

Kohler Porn!  

[jsp_333 273]

Paul,

Took a while but I've got the manual now and, wow, thanks.
Ya it looks like everything is in there, and I'm feeling confident I may actually be able
to get the engine operational.  Thanks again.

John

[jsp_333 273]

Ok got one of the K-90s I purchased running.
Hugely  satisfying.
So naturally I thought I've got the gas, air, spark thing down for one engine - lets take carb, points, plug, air filter from working engine and put it on engine that came with the tractor.
That doesn't work - so put everything back and now working engine won't fire. Naturally.
It's got no spark. 
What are the reasons for no spark other than bad plug/  bad wire.
Is there anything else happening in the engine to produce the spark that I need to look at.
I've eliminated bad plug as the cause. It will spark on another engine when held against the block.

john


 

[AMC RULES 37,141]

Did you check, clean/gap the points. 

[jsp_333 273]

No just took them off the engine that was working put them on another. 
When that engine failed to fire put them back on engine I took them off of.
BTW not the original points from the engine that fired.  The points came off of a third engine and were just screwed into place

[WheelHorse79 271]

If you're ever interested in selling one of K90's that might be made to run, please let me know.  I've been looking for a K90 for my Wife's RJ-58 for a while.

[jsp_333 273]

All I can say at this point is  - you asked first.
If I end up with a working spare that I'm willing to part with I'll let you know.
Cheers,

John

[jsp_333 273]

Wandered around the internet last night and came across two techniques for cleaning points.
Very fine (220 grit) sandpaper or metal finger nail file
Opinions as to which technique is preferred would be appreciated or is this one of those fixes
that is best done by just buying new points

John

[AMC RULES 37,141]

New points are cheap...  
but yeah, slide a piece of fine emory paper through the gap...see what happens. 
 

[jsp_333 273]

Wandered around the internet again yesterday... ya pretty cheap.
This is what's known as a crowbar fix, as in  "stick a crowbar in your wallet you cheap bastard and pay for the thing"

john

[jsp_333 273]

Yet another question.
So I got one of the engines working again which means it's time to turn my attention to the k-90 that came with the rj
So I've got known good (actually they appear to be brand new) points on the engine.
Took a known good spark plug connected the wire to it touched the plug to the engine and turned it over.
Couldn't see a spark.
On one attempt I felt current running through my hand.
Obviously I wasn't holding the plug correctly on that attempt.
Can an engine produce enough of a charge to be felt but not enough to fire a spark plug?
Would that indicate faulty coil - or just faulty operator
 

[WHX?? 49,483]

Yes it is possible if a coil is partial shorted out. Take a resistance reading on a good know coil and compare it to the suspeced bad. Use a new plug when doing the spin test & darken the shop a little to better see if the spark is there and strong or weak.

The other method is to grab ahold of the spark plug lead and give her a spin lke you did before..... if your hair just tickles it's bad....if your teeth fly out it's good.....

I prefer the first method!

[WHX?? 49,483]

Oh and by the way....please..

Killer job on the motor @mikes RJ ...

Edited September 23, 2015 by WHX5

[jsp_333 273]

I've run out of allowable room for pics so once I upgrade to supporter I'll post pics.
Sorry, it's much easier to get a feel for someone else's issue if you can actually see what they're talking about.
I'm on it.

john