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I decided to build up my spare engine

3105 Views 53 Replies 9 Participants Last post by  King_Panther13
I created a thread about this a few weeks ago, asking if I should use my spare engine for parts and build up my current engine, or build up the spare and then just swap. While it'd be most logical to just build mine up, I decided that the most convenient option will be to just build up the spare, as everything that it needs done to it is something I would do to my current engine anyhow.

Now, I want to know if I have the right idea of what all to do with it. I want to make it as perfect as I can. I know that these engines don't take kindly to modding, so unless I find some easy mods that have little risk to negatively affecting my performance, it'll be a stock rebuild.

So far, my list of things to do/get is:

Gasket Kit

Mechanical Seal

G8 Stator

Cam Chain+Tensioner

Piston Rings

Lap Valves

Inspect entire engine, and decoke everything possible.

Clean out and/or replace oil pump

New clutch kit, if current one isn't serviceable

Is there anything else that I should consider, or did I pretty much nail everything?

Oh, and there was a bit of rusty water that came out of the cooling pipes when I removed the radiator. I was told that this can be flushed out after the engine is rebuilt, and put back on the bike. Is this true, or can I get it flushed out before putting it on the bike, so I can get it "perfect?"

Thanks for the advice. This is still a bit off in the future...but the first thing I'm going to do is get the heads serviced (the valve lapping and whatnot) and get my gasket kits. Then I'll slowly do everything else until it's ready.
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If the engine's bottom end and pistons/compression are/were ok then don't touch them and also leave the gearbox alone and just do what you intend.

See this thread as well,

As a check also look at the Cam followers from down top and hopefully they have not been changed and fitted incorrectly.They can be fitted with their cup angles wrong presenting the wrong angle to the push-rods.This causes premature Cam shaft and cam follower wear.

Obviously take the front engine case off and check/service the oil pump chain and assembly and clean the sump area underneath.

I'm unsure of the history of it, thus my want to replace the rings and etc. I've heard that checking compression should be done at WOT...with this engine being detached, does that mean I need to hook some carbs up to it, or is there a separate method to checking compression?

It does turn over just fine when jumping the starter motor, I don't hear anything out of the ordinary, but that's just turning over. I was told that merely inspecting the pistons and crankshaft will require me to replace the rings, which is why it's on my list.

I'll definitely look out for the cam followers, and thanks for that thread.

When I finally get around to working on this engine, I'll use this thread, and post lots of pics
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I don't really want to do the rings and etc, but my uncle who'll be giving me assistance with the rebuild says that "I don't know a single person who has an out of frame engine, and doesn't change the rings while they're in there." He says that it shouldn't be too hard, and all I'll have to take into consideration is that I'll have to break the new rings in.

I figure that I have plenty of time, so it shouldn't be too big of a deal to do. Unless my current engine finally blows up. Then I really need to hurry this one haha.

Now, if I were to just ignore the rings and whatnot, what symptoms will appear if there is something wrong in the crank? Knocking, clicking, or something worse?
I'd look/listen for poor oil psi, and noise.

I wonder if your uncle is used to working on air cooled bikes? IMO they need to be overhauled sooner than a liquid cooled engine.

On my bike with 39,000 miles, I don't get any smoke on start up and it uses very little oil.

Yes. He's only ever worked on one water cooled bike, an older Goldwing, which he never pulled the engine out of. Him and his friends are big on KZs and the old Kawasaki triples, his main bike is a Z1. I'll mention it to him that the CX engine != his old Kaw engines then lol.

My current engine (the non-spare one, that is) seems to be using quite a bit of oil lately. I'll get some clutch slip, look at my dipstick, and the oil is right at add. I'll put in like maybe 1/4th of a court (enough to bring it up to the first diamond) and then maybe a week or so later the clutch will start slipping again and I'll check the oil, and it's back to add again!

No smoke noticeable from the pipes. Once I did see white smoke, but I think that that was from water. Haven't seen any since the one time.

I'd tend to agree with Bandit here, if everything rotates by hand smoothly and you can visually inspect some of the parts you might skip the bottom end tear down. One important but small thing I didn't see mentioned so far are the oil seals. Easy to replace but a PITA if they fail, especially the rear cover one behind the water pump. Two years ago I replaced the cam chain and tensioner along with some other small bits, but I overlooked the front cam shaft oil seal and sure enough, it started leaking just last week.

Also, I know this is your spare engine but you may want to order a new fan along with all the other pieces. Either that or convert to an electric fan.

Thank you! I'll add them to my list. I want to replace everything that can fail due to age or whatever.

I already have an e-fan that I'm going to probably stick on my current engine before even beginning to work on my spare engine. Though I am using the spare engine to fit it, so I don't waste an entire day trying to make it work while I can't go anywhere or something.

With all due respect to your uncle, he knows nothing of CX engines. What he says holds VERY true for about 95% of the bikes that were circulating when the CX was new. On my old BSA I was lucky if I didn't have to do piston rings and head gasket between oil change intervals.

The bottom end of a CX is a very robust, long lived and forgiving thing, just leave it alone if it ain't broke.

No offense taken. He's just trying to make sure I don't cut corners like I've been doing, and he knows very little about water cooled motorcycles. He does know that when I cut corners, usually my bike will end up stuck in his yard for several days until we think up a fix.

What you say makes a lot of sense, and makes me understand what's going through his head a little bit better. This'll make things a hell of a lot easier rebuilding the engine. I'm basically just doing a triple bypass+valve lap, and complete gasket/rubber bits replace.
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I feel like I've asked this already, but don't see the post o.0. Does the Molly stuff go straight into the oil, or does it have to run through the gas?

Anyhow, back to the engine

Since it's been raining all day, I decided that I didn't want to head out and work on my suspension, as planned. I actually love rain riding, but I don't love rain working.

So I started to take apart the spare engine. I removed the fan shroud, and realized that one of the top bolts wasn't the same size as the other. It didn't have a flange on it either. Upon closer inspection, it actually was smaller than the flanged bolt (which is one of the proper bolts) and was coarsely threaded instead of finely threaded. Hmm. Strange, I didn't remember my engine having that. Then it dawned on me that the hole was a smaller, and incorrect size of course -.-. Oh well, as long as I find another bolt that fits and has a flanged top I should be fine.

Anyhow, I turned the left cylinder to TDC on the compression stroke, and then removed the coolant drain bolts. Out came enough fluid to pool up, and drip on the floor. Maybe, I dunno, half a cup or so, if even that much. I soaked some up with a paper towel and it smelled just like normal water. No other scents detected. Now, it's obvious that the PO ran this thing with water instead of coolant because of the rusted up coolant pipes, but should I be worried that water came out after removing those drain bolts, or is that to be expected?

I hope I don't run into too many other "surprises" along the way. The fan shroud bolt hole imo is a very strange one to have stripped, or have a broken off bolt in. Dunno why it was helicoiled. But it seems to be aligned properly, so I guess I'll leave it.

Now I'm about to actually remove the head. Let's see how badly I screw it up
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You will get about of cup of coolant out of the cylinder drain plugs, as it lets out the coolant stuck in the head passages that cant drain by gravity to the bottom coolant hose, so its normal. I would recommend a flush before finishing up and adding coolant.

Take some pics and post them of the heads and cylinders, and people here can tell you what they think. As for valve guides, I would check them (replace them only if they are bad) and lap the valves as it makes a huge difference. I picked up a set of valve oil seals when I did my heads off Ebay, and they were not that expensive for a set of 8. chances are when you check the valve guides they may be ok, the manual gives you the slack and wiggle values.

Yeah, I'm going to flush the crap out of the system before actually running it. The rust looks kind of bad, but I've heard that it's not hard to flush out. I'll be getting my camera fixed soon so I'll be able to take some pics. I would have done it today if it wasn't raining. Fixing my camera goes hand in hand with working on my suspension issues...I'm bugging the same uncle to help me with both hehe.

Anyhow, I've been trying to get the hold-down bolts out, and they just won't budge. At first I was afraid to put too much pressure on them, but I was able to make each one *click* like it just broke loose. I've been doing the criss-cross pattern the manual suggests. I think that the click may have been in my socket, as it looks like each bolt took small chunks out of it.

I tried using my extended socket so I wouldn't have to use my extension and a smaller socket... I held the engine still, pushed, and heard a snap. I thought that I broke the bolt loose finally, but it broke the socket itself! Holy crap these are tight.

I'm deathly afraid of breaking something or rounding out another bolt. Should these really be in this tight? Did I possibly miss something? Cylinder is definitely at TDC on the compression stroke, and I removed the smaller bolts on the outside of the cylinder already.

Is this a good place to use penetrating oil, or should I just keep muscling until they finally break loose?
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NP Vtype. I'll be doing the same once I get this engine built up...interesting stuff.

Anyhow, I'm still trying to get the hold-down bolts loose. They are REALLY tight in there. I tried rotating to TDC on the right cylinder, and breaking those loose, but they're just as tight.

Can I use penetrating oil on those, or are they in a bad location? I even called in my father to lend me a hand, and we broke the chair that the engine was sitting on because of how damn tight they are.

Are you using good quality 6 point sockets? They will help you in not rounding the heads of the bolts off.

Have you shown your uncle this thread?

Good luck!

My uncle doesn't know how to use the internet
But I'll show it to him when I get to him for the other things.

I'd been using my six point 14mm socket with my 3/8 inch drive wrench. We were able to get just one of the bolts to budge. I have a 1/2 inch drive wrench with a much larger handle, but only old 12 point sockets that I didn't trust too much. I was afraid of rounding out my bolts. I was convinced to try it with just a small amount of pressure, and everything broke loose evenly. Nice. I need to buy some 1/2 inch drive 6 point sockets now. They all came out with very minimal damage to the points. Not nearly enough to be considered rounding.

Now I'm busy knocking at it with the rubber mallet and pulling it all apart. I'll be doing the right side tonight too now that I'm on a roll.
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I don't own any breaker bars, though I think that my click type torque wrench is designed to work as one. Maybe I should grab one. None of the sockets I've used on the thing are cheap, but as you said, probably not the right type. I think if I get some good 1/2 inch drive 6 point sockets I should be fine for the right cylinder. Or maybe a breaker bar as you said.

Anyhow, after removing the rocker assembly we tried to get the head off and it just wouldn't budge. Whacked at it for a while with the rubber mallet to no avail. It looks like the PO was overzealous with gasket sealer ,as evidenced by the huge amount I found gunked up in one of the water pipes. Yikes. So I decided to spray some penetrating oil around the gasket, and let it sit for the night. Hopefully that's not a bad place to be spraying the stuff, but I figure I'm going to have to replace the gasket anyhow, so why not.
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Well I was wondering about the torque wrench because it says on the package "Left and right hand drive. Torque reading only works on right hand drive." Then says to never use it to tighten or loosen bolts. I was wondering if that was just a generic warning, or if they really put a left hand drive on the thing that literally couldn't be used.

Anyhow, still whacking at the head. I'm tempted to try FADM's idea of banging a knife or maybe a flathead screwdriver into the gasket with a hammer, but I'm afraid of destroying the seating surface for the gasket. Taking my lunch break now. Don't think I want to spend the whole day whacking on it since it's nice out.
Bandit, I understand that it would be necessary in some cases to torque something with a lefthanded thread, but it says that the torque values only work when it's set to right handed drive o.0. Which means the left hand drive is effectively useless.

Thanks for that tip though, now I know where to bang! I have an old wooden wire brush that I was using as a chisel, but didn't know where I really should have been hitting. I'll get back to it.
Agh, I should've done that instead FADM. I ended up using a flathead screwdriver, thinking that if I did it straight in I'd be fine. Well, I was fine on one of the sides, but the other has a nice little "hump" I put in. I think I may be able to smooth it out with some emery cloth or something.

Anyhow, did that and it pried the head right up. Now, for a few issues. I was doing this where I thought there would be dowels. I was thinking that the dowels on the lower part of the head would be at the same place they were on the top part of the in, the ones that reside in the rocker arm assembly. When I got the head off, there weren't any there. However, there was one smaller one that was quite a bit rusted in a separate area, and the second one that was supposed to complement it was missing. I looked around to see if maybe they flew out when I got the head off, but saw nothing. I also found a tiny O-Ring, but wasn't sure of where it came from. I sat it where I wouldn't lose it. I'll get into details of what I saw in the cylinder after I talk about the right cylinder.

We switched the engine to TDC on the right side, and used our 1/2 inch drive wrench with the 12 point socket, because I was too lazy to go out and buy a 6 point. I told myself that if it even HINTED at slipping, I'd stop and go to the six...and I will definitely get a six when I'm torquing them back in. Well, each of the bolts came out easily using the criss cross pattern. Removed the rocker arm assembly, and whacked the head with a rubber mallet, and this one literally came right off with very little effort. It also didn't have dowels where I thought they'd be, but it did have both of the smaller dowels, also quite rusty. But it seems as if this cylinder is using a different gasket than the left is a metal type material, which reminds me of a cheese grater. The other just seemed like a normal type gasket. I didn't find any tiny o-rings on this side.

In both cylinders, the "ring" around the "cup" that the piston resides in was very rusty, but I think that that's where the water from the radiator goes. If that's the case, then that should be expected. The valves on the right side were all very very black, on the left side very black and two of them with a tinge of brown. There was no rust in the "cups" that the pistons sat in, though there was a good amount of carbon build up, and the pistons themselves had a lot of carbon and maybe a bit of a hint of rust on top.

Anyhow, excuse my noobness at engine terms, this is the first time I've ever had major components of an engine of any sort off before. I'm about to leave to finally fix my camera, and when I get home I'll take pics.
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Hmm, it was suggested to me by Mr. "You must do the piston rings!!!" that I should just bring the heads to an auto shop and have them lap them. That may make things a bit easier, depending on the price. He said that when he did it it "didn't cost much" but it was so long ago he doesn't remember the price. If it's overly expensive, I'll buy the stick and do it myself. For something like this, I want to ensure that its being done properly and as good as it can be done. I'll get the valve seals when I pony up the cash for my complete gasket set. I'm not in any hurry to do this, and it may be a few weeks until I do something to the engine again.

I heard that some kind of pin or ring or something was supposed to be swapped or switched to make setting the tappets easier in the future. Could you point out on the diagram what it is, so I don't mess with the wrong piece?

Oh, and as promised, I took some pics...but it's dark now so I wasn't able to get the very best shots of the cylinders, but I think that the shots of the heads are more than adequate:

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I was tooling around for gasket kits....found this kit here for a LOT cheaper than the ones recommended to me. It seems like it doesn't have the rear cover gasket in it, and probably is missing other things that I can't quite spot...however, Buying this rear cover and that kit would save me a lot of cash.

That just boils down to...what out of that top end kit is missing that a normal "full" kit would have? Other than rear+front cover gaskets, which seem like they can be very easily sourced for less than the price of buying a full kit.

I'm really cheap. Well, rather, really The sooner I get the gaskets the sooner I can move on to buying other things. If only my hours would pick up, I'd be fine. To think I tell my job I'm willing to work every day over the summer, and they respond by giving me LESS hours!
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I think I need pretty much every gasket...I mean, I'm doing a complete overhaul, save for the crankshaft/piston/etc. It just seems like paying 38 for the head gaskets and whatnot, and then 10-15 (after shipping) for the rear/front cover gaskets will be a lot cheaper than paying 80 bucks and shipping for a complete kit. Though, upon thinking about it a bit more..not really *too* much cheaper. So maybe I'll wait till I can scrounge up the 80 bucks.

As for storing the bits and pieces, I'll probably use pill bottles, or old plastic bottles or something. Toldja I'm cheap
. My uncle who told me that it "doesn't cost much" to get the valves lapped and seated by a shop has a valve spring compressor that he'd let me if I call that auto shop and it turns out to be too expensive, then I'll probably be able to lap the valves for 5 bucks. I'd probably be willing to spend 20-40 bucks to get them lapped just because it'd be less of a pain, but then comes the whole money issue...I could save that cash and do it myself, and be that much closer to my gaskets and all of the other bits and pieces.

And it's great that they look good to you guys. I didn't think they looked bad as much as I thought that they looked dirty. The only thing that concerns me is the rust/orange gunk in the ring around the piston...or I guess the "moat" around it would be a better term. But that's part of the cooling system I think, so that'll probably get flushed out when I run vinegar and stuff through it.
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For those that are/were following this thread, I decided to consolidate it all over to this thread over here, as now the goal is to get tihs spare engine up and running as soon as possible since my current engine just can't be trusted.

I just got the rear cover off, and now I'm trying to find the best deal on a gasket kit.
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