Clutch question

[n4mwd]

I've got the two side cover gaskets (new). I still need a new oil screen gasket.

Can the head gaskets be reused? If they are like other engines I've rebuilt, they are made of metal.

11004-1312 Head Gasket, Upper
11009-1572 CYLINDER BASE GASKET

What others do I need? Does anybody make a gasket set for these things?

I haven't split one of these engines before so I don't know what's involved.

[Racer x]

The gaskets are metal but it is stamped and dented to form seals. When you clamp the gasket you flatten it out. I scrub them with a scotch bright and spray them with copper coat then let it dry completely.

The engine is easy to work with . Just clean everything really well. Follow the manual and don't force anything.

There are bolts in the oil filter housing and under the starter. Don't forget them when you split the case

[n4mwd]

Is it mandatory to remove the heads? Or can I just leave them alone?

[alex.s]

you can take off the bottom without removing the head dont know if youll be able to see allthe bearing surfaces without taking the crank out

[n4mwd]

If I understood racerx correctly, it sounds like I can just yank out the crank with rods and pistons still attached.

BTW, do the two halves just go back together with plain blue RTV?

[Racer x]

Not pistons . You can take the crank out with the rods still bolted to the crank. But you have to remove the pistons.
If you just want to look for junk I the case . Leave the top end together. You can remove the bottom of the case and pull out the trans and get to all the places metal can hide.

[Motofool]

Originally Posted by n4mwd

I took the oil screen off to check it and surprise - there was a bunch of metal flakes in there. ......... There were all assorted sizes - little dusty ones and several jumbo ones.

There is no apparent source for those steel flakes.
How thick are them?
Could they be just little particles glued together adopting the shape of the mesh?
I have never seem steel flakes inside an engine.

[n4mwd]

There is an assortment of sizes. There are several just like the one in the penny picture. They are foil like and definitely made of steel.

What do you guys use for "liquid gasket" to seal back the two halves? I was thinking of using Blue RTV, but I'm concerned it might not hold up to oil.

[alex.s]

i think the rtv i use is black

maybe the flakes are from this:

[n4mwd]

Originally Posted by alex.s

i think the rtv i use is black

maybe the flakes are from this:

I've been working all morning trying to figure out a way to mount it in my engine stand. I've seen other people hook it to the two rear engine mounts, but that means I can't split the case since one is on the bottom. I need to hook to the top rear mount and also the front mount. Fun for sure.

Anyhow, the assumption that the debris came from the clutch is probably a good gamble. I doubt the main bearings are damaged unless the guy ran it without oil or something. So far there has been no indication of that. Now that you pointed that out, I think I'll just put it back together and see what it does when its actually running since I never actually saw it do that. I may end up splitting it anyway, but for now I'll just chance it. It may also give me the opportunity to check the oil screen after a few miles to see if there are more shavings there.

[alex.s]

K just be careful, if it is a bearing and you run it for long, you could turn a bearing replacement into a bearing, crankshaft, piston, cylinder and head replacement.

[n4mwd]

Originally Posted by alex.s

K just be careful, if it is a bearing and you run it for long, you could turn a bearing replacement into a bearing, crankshaft, piston, cylinder and head replacement.

I may have to take the engine right back off, but the thing is that I have no idea what exactly was going on when the guy said "The oil pump is bad and the engine is making noise." It could have been and probably was the clutch mess making noise and/or the unsync'ed carbs. At least this way I can hear it run and decide for myself what kind of noise it is.

Anyhow, I finally finished making my angles for the engine stand. It takes longer for me to do stuff because the garage is a mess. Now its off to the hardware store to buy some grade 8 bolts for mounting the angles to the stand.

[alex.s]

Originally Posted by n4mwd

I may have to take the engine right back off, but the thing is that I have no idea what exactly was going on when the guy said "The oil pump is bad and the engine is making noise." It could have been and probably was the clutch mess making noise and/or the unsync'ed carbs. At least this way I can hear it run and decide for myself what kind of noise it is.

Anyhow, I finally finished making my angles for the engine stand. It takes longer for me to do stuff because the garage is a mess. Now its off to the hardware store to buy some grade 8 bolts for mounting the angles to the stand.

yeah you should be able to tell pretty quickly

[Racer x]

Honda bond to go between the case half's. NO RTV. There is not much steel in there. Foil like that looks like bearing material to me. Do you still have the bits. Can you photo more.

[n4mwd]

Here is another photo. Not as much detail as I'd like, but there are several smaller flakes on the screen at the bottom and a larger on top. The piece in the foreground is a rather substantial hunk of steel. The photo resolution is 1024x768. You can see a little better full size.

[n4mwd]

I googled HondaBond. Looks like the correct kind is "HondaBond HT." There is a HondaBond 4, but its not recommended for engines. Its basically just oil resistant silicone. I'm not sure how it differs from the black silicone RTV. However, I did read that it is much thinner, like paint, and is easier to spread.

But what worries me is whether its hard to keep it from running into areas where it doesn't belong - like into bearings.

Anyhow, regarding the particles. I've had the screen off two other Ninjas, and I've never seen this much material before.

Regarding the gaskets, do I need to change the main output seal? Or just reuse it.

[n4mwd]

I have finished the brackets for the engine stand and that works good.

However, when trying to take everything off to split the cases, the oil banjo bolt for the oil tube is being really stubborn. Its starting to feel like a disaster is pending. The bolt seems to be made of some kind of super soft brass or maybe copper. The bolt was bunged up when I got to it. I tried the impact wrench on low torque, but that just nicely rounded all the corners off.

Its in a tight spot so its hard to get vice grips and tools like that on it.

I've tried using a chisel to turn it, but the chisel just cuts right through the head.

Because the bolt head was already bunged up, my theory is that the previous owner took it off and used some kind of thread locker on it. Possibly plugging something up in the process, resulting in the metal shavings I found earlier.

So I'm going to try heating it with a torch to see if that frees it.

[alex.s]

oh crap

good news and bad news i guess

[n4mwd]

Originally Posted by alex.s

oh crap

good news and bad news i guess

I went to Harbor Freight and bought a
9 Piece 3/8" Drive Metric Bolt Extractor Sockets

Worked like a champ. No torch either. However, my theory about the PO using locktite on that bolt just got busted. I still need to buy a new bolt, but they aren't that bad.

I also got my new clutch cover and clutch basket assembly. The old clutch cover was definitely bad. Somehow the pin was bent. I haven't measured it yet, but my best guess is that the original clutch basket assembly is not defective judging by the new one.

I think I have most everything ready to split the case.

[n4mwd]

I split the case and it looks like that was the correct decision. The bearings look OK except for the rod bearings. Those look like aluminum foil. Essentially, they are gone. The rods could be shaken back and forth on the pins before I unbolted them. Definitely not a pretty sight.

The other crank bearings seem OK.
The balancer bearings looks OK.
The transmission looks OK, but I can't get it to go into 2nd or above.

The case was peppered with little piles of steel flakes. The oil screen was just the tip of the iceberg.

Next up: I have to figure out how to remove the cam chain so I can get the crank out and see how much damage is there.

Also, with all that debris in there, I need to look at the transmission bearings to make sure they haven't been damaged.

[alex.s]

Originally Posted by n4mwd

I split the case and it looks like that was the correct decision. The bearings look OK except for the rod bearings. Those look like aluminum foil. Essentially, they are gone. The rods could be shaken back and forth on the pins before I unbolted them. Definitely not a pretty sight.

The other crank bearings seem OK.
The balancer bearings looks OK.
The transmission looks OK, but I can't get it to go into 2nd or above.

The case was peppered with little piles of steel flakes. The oil screen was just the tip of the iceberg.

Next up: I have to figure out how to remove the cam chain so I can get the crank out and see how much damage is there.

Also, with all that debris in there, I need to look at the transmission bearings to make sure they haven't been damaged.

trans does that. the output shaft and the other side need to spin at different speeds. you can reach in and move one to get it to slide in. hopefully its just the bearings and not all the way through the bearings? maybe you can get away just replacing the bearing surfaces which are pretty cheap. buying a new crank is kinda expensive :/ i wonder if the piston was hitting the head at all. have you looked at the pistons or head yet?

make sure if you do save the poor thing you thoroughly clean all the debris out, the wrong little piece stuck in there could cause a world of hurt later on.

[n4mwd]

The crank pin bearings are shown in the attached photo. Essentially, they're gone. The crank pins look a bit rough.

Anybody turned Ninja cranks down before? What's the process?

But more importantly, what the heck caused the crank bearings from getting oil? I don't want to put it back together until I know that.

[alex.s]

:/

same thing happened to kevins 636. oil pump and everything else seemed alright, but those crank journal bearings blew out. he replaced the entire crank and pistons and rods with a used set from a running engine.

probably cheaper/more cost effective to buy a new engine unfortunately. if you're in it for the experience, you can take the crank to get it checked and machined and put on new bearings. or just buy a different crank/rods/pistons

[Motofool]

Originally Posted by n4mwd

The crank pin bearings are shown in the attached photo. Essentially, they're gone. The crank pins look a bit rough.

Anybody turned Ninja cranks down before? What's the process?

But more importantly, what the heck caused the crank bearings from getting oil? I don't want to put it back together until I know that.

Yikes!

No Ninja's, but I know that any crank needs to be repaired in a cylindrical grinder (specialized machine shop) and then use over-sized bearings (if the factory makes them).

The metal of the bearing is soft on purpose, so when lubrication fails, it melts and somehow protects the harder surface of the crankshaft.

If that surface is only pitted, but the diameter and roundness is intact, it can be reused with standard bearings.

The service manual shows how to test the lubrication pressure; do you have a repair manual?

I agree with Alex.
How some people can cause so much damage to an engine like this one?

[n4mwd]

The crank rod journals are roughed up, but I'm not sure how bad they are. There isn't much room for turning them according to the manual. It says that acceptable diameters go from 29.984 MM to 30.000 MM (pg 8-4). And that if it gets below 29.970 MM to throw the crank away. I'm used to measuring in thousandths of an inch, but this is the first time I've seen something measured in thousandths of a millimeter.

The rod end journals on my crank are measuring about 29.64 MM. If they get turned, they will be even less than that.

I know there are ways to add metal to the journal prior to turning. I am going to take it in on Monday to see what the machine shop guy says.

I don't see any evidence that the pistons or cylinder walls are bad. I looked from the bottom and there is no signs of scoring - so for now, I'm going to leave them alone. The head was not removed.

As for why it failed, its obvious that the rod bearings didn't get enough oil, but as far as I can tell, they are the only ones that are bad. So this tells me:

A) The rod bearings need more oil than other bearings due to the pounding they take. Did Kevin's 636 fail on all rod bearings or just one or two? If all the rod bearings failed, it could be that the oil pressure was low, but not low enough to trip the oil light sensor.

B) Its possible the crank's internal oil passages are clogged. See the attached diagram. The oil is fed straight from the oil filter to the center crank bearing. From there it goes to the two rod bearings through the crank. I still need to check the crank passages, but its unlikely that both sides would simultaneously clog.

C) There are four ways that oil pressure can drop.
1) The pump fails.
2) The oil pressure regulator fails.
3) An excessive internal/external leak.
4) Some idiot ran it without oil.

I'm going to test the pressure regulator and other stuff to see if I can find anything. I would really hate to assume that it was that the guy ran it without oil. That seems like a stretch. I would be very uncomfortable putting it back together under that assumption.

In any case, its starting to look like I'm going to have to get a new crank. But I'll wait to see what the machine shop guy says.

[n4mwd]

I just got back from the machine shop. He said he could fix it for a minimum of $300. They either weld or plate the journals and then turn them to factory spec. Or I could buy a new crank. Either way, he said I also need new rods.

I asked what could cause it to do that, long story short, he said many times these bikes will get leaky petcocks (which the previous owner said he replaced) which leak gas into the crankcase. If the engine is run in that condition, the rods and crank journals are damaged because the thinned oil is inadequate to lubricate them with all the beating they take at such a high RPM that the Ninja runs at.

He said that the guy probably went into the clutch thinking that was the problem. This bike MUST have been knocking and he may have mistaken clutch basket ticking with rod knock.

Bottom line is that my project may be shelved for a while.

Lessons learned:

1) If the seller can't or wont start the engine, offer a price for the bike assuming the engine needs replacing.

2) Change the oil often and with the right stuff.

3) Don't ignore a leaky petcock and don't run a bike with gas in the oil.

Oh, and he gave me one final warning. He said that he would guarantee that if I didn't find the problem for sure that caused the bearings to fail, that the new crank would go bad too. The petcock and thin oil seem like a good theory, but how can I know for sure?

[alex.s]

we just finished kevins 636 rebuild which had pretty much identical damage. we found there was a few of what looked like orings between the oil passages transfer between pieces that looked completely melted. it plugged up one of the passages a bit. my theory is that the bike was neglected, coolant and oil got old and nasty, the bike overheated and melted the oring blocking the passage starving the bearing which gave enough clearance to slam the piston into the head cracking it in half.

you might want to take a long pipe cleaner or something softer that wont scratch as it bends/deforms and run it through all the oil passages... i have the feeling youll find one of them is jammed up with something.


looking at parts for this engine, im amazed. everything is ridiulously cheap for even new parts. you might be able to fix the engine for reasonably cheap. but like your mechanic said, if you dont find the cause, chances are its just going to break again

i dont really buy a small amount of gas in the oil causing damage like that but thats just me

[n4mwd]

Originally Posted by alex.s

i dont really buy a small amount of gas in the oil causing damage like that but thats just me

I've never heard of that before either, but the bike had sat for two years so I think their was more than a little gas in there. One thing for sure is that when I took it apart, ALL the bearings, including the bad ones, were covered in oil. He said that he recently changed the oil and then ran it like that.

I also know that the oil pump is designed for thicker liquids. There is too much slop for it to pump gasoline. If the oil was too thin, I can guarantee the pressure and volume would suffer.

But I still can't say for a fact that that was it.

So for now, its shelved until I can either find a crank with rods attached or a new engine.

The dealer lists a different part number for the 2006-2007 bikes.

13031-1247 --- 1988-2005 only
13031-0013 --- 2006-2007 only
13031-0112 --- 2008 only
13031-0120 --- 2009-2010 only

Anybody know what the differences are? Until I know for sure, I'm going to have to get the 2006-2007 cranks only.

[alex.s]

i know the timing is different between pregen and postgen. outside of that i cant tell you anything more.

was the crank case breather still attached to the airbox? if so theres not really any way the gas could have gotten into the case while it was sitting there.

i mean... you could overflow your carbs from a leaking petcock and float valves... but that small amount of gas even if it leaked directly into the cylinder i dont think would do anything but gum up the place. and i would think if the petcock and float valves gave, it would start leaking somewhat quickly (if it was dead slow, the gas would evaporate quicker than it could leak into the engine) and if it was leaking quickly, i would think it would start overflowing the gas out of the carb overflows faster than it would leak through the pilot jet into the engine...

[n4mwd]

Well the petcock theory seems to be having trouble. However, I do know that people have reported that a faulty petcock filled up their crankcase with gas overnight.

The PO said that he replaced the petcock and the carbs. When I asked about getting the old carbs, he said they were "Beyond repair". Which tells me that he tried to rebuild them and mucked them up in the process.

Anyhow, I'm open to getting a new engine if I can get one for a reasonable price. Actually, preferably unreasonably low priced.

As far as the pregen cranks, the 2006-2007 crank is about $100 cheaper at the dealer than the other pregens. However, it uses the same bearings. So its the same diameter shaft and journals.

[alex.s]

well the stroke and bore for all the years is exactly the same right? if the stroke is the same, the bearing sizes and alignment (bearings X position relative to eachother and the cam chain sprocket) are the same, i would think the only thing that could be different is the timing and angle of the cams and things like the weight. which... changing the timing i dont think would have a massive effect... outside of fine tuning stuff but i could be wrong. and the weight... depends on how much but maybe it would make it vibrate more? i really dont know.

[CZroe]

Originally Posted by n4mwd

I just got back from the machine shop. He said he could fix it for a minimum of $300. They either weld or plate the journals and then turn them to factory spec. Or I could buy a new crank. Either way, he said I also need new rods.

I asked what could cause it to do that, long story short, he said many times these bikes will get leaky petcocks (which the previous owner said he replaced) which leak gas into the crankcase. If the engine is run in that condition, the rods and crank journals are damaged because the thinned oil is inadequate to lubricate them with all the beating they take at such a high RPM that the Ninja runs at.

He said that the guy probably went into the clutch thinking that was the problem. This bike MUST have been knocking and he may have mistaken clutch basket ticking with rod knock.

Hmm. This is all entirely over my head, but my newgen's oil has smelled strongly of gas the last few times I changed it and turned dark rather quickly. I know that my petcock leaks like many other newgens because it leaked all over Casey's garage when he did my valve job. Perhaps what I thought was a rattling cam chain is actually something else? The excessive rattle noise seems to go away when fully warm, which could imply that oil finally got to one of these rods you speak of.

[n4mwd]

Well I found another Ninja 250 on Craigslist for $300. I thought that the problem was solved, but when I called the guy he said he forgot to mention that the engine was seized. Oh, well. Still not a bad deal. I let it go because I already have a bike with a blown engine. Might be OK for someone else - if they are OK with the green ones.

Anyhow, back to the crank years. The counterbalancer is the same 82-07. So that implies that the balancer gear and the weight and timing of the crank is the same. The clutch basket is also the same from 1988 which says that the main drive gear is the same. Also, the engine case is the same since 2001 so the bearing positioning is the same.

Since all the parts that the crank interacts with are the same, I have to assume that the only difference is maybe a paint job or something. Maybe they used a different manufacturing process or something. That would explain why its cheaper.

[n4mwd]

Does anybody know if the newgen engine will fit on a pregen frame?

I have been looking at photos and it looks like the mounts may be similar.

[CZroe]

Originally Posted by n4mwd

Does anybody know if the newgen engine will fit on a pregen frame?

I have been looking at photos and it looks like the mounts may be similar.

It's been discussed. IIRC, the headers won't fit and the angle is different (could cause problems getting oil from the sump). The sprocket alignment might be slightly different (see the difference in output sprockets between the generations).

[lolibater]

Just gave this a thorough read through for some evening entertainment. Hats off to you for your persistence. Did you ever get a new engine for that bike?