CH18 swap issues

[Redblower]

I think this is the right place for this, you may have seen my thread started a few months ago about swapping a CH18s into my 682. It's warmed up a little here and I've been out in the barn playing around with the motor just thinking to get it started and see if there were any issues.
Well it really started bugging me how hard it was to turn over, when I bought it since it was out of a tractor I could roll it over slowly by the crank shaft, I assumed since it had plugs in that was about how it should be, this weekend I hooked it to a 500+ cranking amp boat battery and it would barely roll over so put a wrench on the end of the crank shaft with the plugs out and it really is hard to roll around, not impossible but really stiff.
So got out the service manual and started tearing it down, got to taking the intake manifold off and found this, I'm just a shade tree wrencher but i'm guessing this isn't good, I also noticed some what I would assume are after market markings on the jugs, #1 which appears to be marked 16-22, 9-7 is the one with all the white deposits in the intake port, #2 just has an x on it in the same paint pen.
I won't bore you with my fears and speculations, thoughts?
Also attached a pic of the engine tag.
IMG_4013.jpgIMG_4020.jpgIMG_3526.JPG
Thanks in advance!

[jaynjeep]

That's not good.. not sure about the markings but appears it had something sitting in the engine for a while.. maybe just moisture.. might as well pull the heads and have a look..

[Redblower]

Hey Jay, how are you doing? Been wondering how this winter has been treating you.
Yes that is what I thought, not good, just ran out of time the other day, but then the service manual starts saying things that I have heard but never done and am unsure of, like "use a hydraulic lifter tool to remove lifters" is that something I can buy? from Kohler? or make?
I am willing to wrench on anything but don't want to mess this up, I've not been past taking the heads off of the KT17 or dropping the crank on a 351w and sliding in a new rod bearing (was a long time ago, not sure if that is even the right term anymore?) in my travels through a motor.
Can I pull the heads without worrying about the lifters? just leave everything attached to the heads?
I know this is just the beginning...
Thanks,

[jaynjeep]

Hi Vic.. I'm getting there.. had a rough last year and haven't been around on here much.. sorry to see you are having issues.. Those commands are super easy to work on.. hope it's not too bad inside..

[J-Mech]

That doesn't look good Vic. Definitely pull the heads. No, you don't need the lifter tool. All that tool does is reach in to grab them to pull them out of the block. I don't even own one. There's plenty of tools that can get them out. But, unless you have to go deeper, they stay in. If you can't bar the engine over however, you will probably be going all the way. Sorry bud.

[Redblower]

Hey Johnathan, I bought one today but it wouldn't work if I did need it, too short, I'll just take it back, I can bar it over it just seems really tight to me, I hope to get the heads off soon, supposed to get cold again tomorrow so might not be till the weekend. Reading the service manual I'm seeing where not supposed to use the head bolts again, I assume that is something that is readily available along with the gaskets I'll be needing.
One other thing I forgot to mention, when I picked this motor up the po said oil change and new filter, oil did look new and didn't have any burn smell to it but when I took the filter off it was dry inside, oil change and filter must have just been window dressing...
Does anyone speculate that the scribbling on the jug is indication that it has been serviced before, seems to make sense to me?
Thanks, I'm sure I'll be back with more...

[J-Mech]

Vic, the lifters are down under the head. Once you get it off, they are closer to the deck. Don't be sure your tool is too short. (I'm not sure that came out right...)

As far as the paint pen writing on the jug, it's hard to tell. Since the intake covers it, it was either done at the factory, or it has been apart before. Hard to tell. *Usually* those kinds of things are done by mechanics (or salvage yards in the automotive world).

I wouldn't get too hung up on head bolt replacement. Not like these little engine are using torque to yield bolts. They only torque to like 18 ft lbs or 22 or something low like that. Plus, you never order parts until after teardown and inspection. Get it torn apart first, then worry about finding the parts you need.

[Redblower]

Oh Boy Jonathon, that's bad! Ha! Ha! Ha! Dang, making my belly hurt!
Alright, we'll just wait to see what I find after the tear down, quit speculating and go from the facts of what I find.
Thanks for all of the help (I think...)

[Redblower]

Ok, so got the heads off today and valves out, first pic is the view into the intake port with that white crystal crap all over.
Second pic is after that valve was removed, pretty much the same thing, different angle.
Third pic is typical of both cylinders, pretty heavy on the carbon deposits but both bores are smooth and by the way once the heads were off it turned over with very little effort.
I had pumped a couple of squirts of oil into both cylinders which was still sitting on top once the heads were removed, seems like that is a good sign?
Fourth pic is typical of both heads, same as cylinders, pretty heavy on the carbon deposits.
Last pic is of that intake valve with the white crystal crap, what the heck happened here side?
I have plenty of questions but maybe best to just let you speak to what I have shown here first and go from there, well I have to ask at least a couple of nagging questions...
Why would the service manual say not to use a magnet to remove the hydraulic lifters???
How best to clean these heads?
Can I clean those piston heads in the block, carbon seems pretty loose and could be done easily?


IMG_4045.jpgIMG_4050.jpgIMG_4041.jpgIMG_4043.jpgIMG_4049.jpg
Thanks!

[jaynjeep]

Looks like you are on your way to getting it fixed Vic.. might need a valve.. and a valve job but i'm betting you can clean the rest of it up.. I have no idea why you aren't supposed to use a magnet to pull the lifters.. I've done it before! But don't think you need to go that deep.. I'd like to know what went in that one side? Must've been pretty corrosive.

[Redblower]

It’s looking like we’ll never know what that was unless some comes along that has seen it before.
I have a gallon of carb cleaner, just seems like some solvent, was going to brush it on the heads and loosen all of that carbon up so I can wipe it off.
So should I clean that valve off and give it a good inspection to determine if it needs replaced, what am I looking for? I know it needs to seat right and all that, when a valve is replaced do you replace the seat too?
Also wonder if I should open the crank case since I’m this far just to check and clean things up? Can I just remove the front cover to do that?
Thanks!

[J-Mech]

I've seen it before. Many, many times. It is aluminum corrosion from water getting into the port. Basically the aluminum equivalent of rust.

DO NOT use carb cleaner on aluminum unless it says it is safe for aluminum. Carb cleaner is best left for carb work. Clean the heads with mineral spirits.

The valve and head are likely salvageable, but the seat and valve will need to be ground. I can see the rust on both the seat and the valve. This requires special tooling. You will have to take it to a shop to have it done. No, you do not replace a seat when replacing a valve. Some seats are made to be replaced, some are not. In an aluminum head, you are better off getting a new head if the seats are bad. On some heads, they do not have a seat, as it is just a cast part of the head that is machined. You have to have that area cut out and a seat installed. Anymore, this is very expensive work and unless you are dealing with a hard to find engine part, not many places will do it anymore. On this Kohler head, if there is a problem with the seat or the guide, just buy a new head. They aren't that expensive. Probably cheaper than driving to a shop and paying for the work. New heads are between $100 and $120 for a bare head, $200 for a head with all head parts, so, new valves, springs, keepers, spring caps and rotators, rockers, rocker studs, pushrods and pushrod guides.

I wouldn't open the engine up unless for good reason. If the front cover doesn't look like it is leaking, and there was no water in the oil, and the engine turns over smooth, I would just focus my attention to the head.

Yes, you can clean the top of the pistons while they are installed. Just put them to the top of the bore, clean them and blow out the crud that fell between the piston and the cylinder wall. Then roll it to the bottom, spray some brake cleaner in the cylinder and onto the top of the piston and blow it out again. Rub a light coat of oil on the cylinder walls to keep them from rusting, run the piston up and down a couple times and you are fine.

[Redblower]

Well that sounds a lot easier, the front cover is virtually spotless, no seeping around the seal or anything like that and no water in the oil. It did look like aluminum oxidization but I've never seen it that "crystal thick" like that before.

Pics below of both intake and exhaust valves, I think the intake is on the right but now can't remember which one I took first? I don't know if you can see it but I think they are both a little pitted in the seat area, hard to get a pic, I'll just take both into the shop with the head and have them do it up.

I think I meant to say seal not seat, service manual says to replace the intake seal if the valve is removed, but it doesn't describe how that is done, is it pressed in? Then I should have a new one handy when I take to the shop? But from what I can see nothing that could be drastically wrong here, everything seems to be in good shape other than the pitting.

I will clean the heads as noted, maybe this won't be so bad after all.
IMG_4052.jpgIMG_4051.jpg

Thanks,

[Redblower]

Next issue, ordering parts, I don't know for sure what tractor model this motor came out of, I have it on experienced advise that it was a 1993 - 1863 or 1864. I ran the spec. no. through the Kohler website and am coming up with the same part numbers as a 1863 or 1864 of the same serial number group that I'm getting on Cub Cadets Parts Look up and on Parts Tree, seems like I should be safe?
Thanks,

[J-Mech]

Doesn't matter what tractor it came out of, engine serial number is what is important. There were some design changes in the head depending when the motor was built. I think all the head gaskets were the same, but do not remember for sure.

Yes, get new valve seals. Shop will know how to install them. Should come in a head gasket set, but if not buy individually.

[Redblower]

Thanks!

[Redblower]

Finally received head gasket set and valve seals, ready to take the heads into the shop next week (if they don't shut down every last breath in this state).

Situation; since I thought I was tearing all the way down I did remove the lifters before I saw John's advice not to, reading the service manual on re-installation it says to bleed the lifters by putting a 3" chunk of push rod in the chuck of a drill press and pump it a few times to pump the oil out of lifter, tried this today and met resistance, no movement at all (note- I have a small drill press). I could use the "real" drill press we have at work.
Also wondering about the special lube to put on the face of the lifter upon re-install, something I assume I can get from my local parts shop? any special designation?

As always, advice is appreciated.