Topic: removing stuck pistons, rotating engine to get cam loose,brake fluid

[crusierlover]

My manual is for the 79.It says use dot 3.I doubt that is made.I have dot 4, have seen dot 5.I heard dot 5 is only for newer bikes with certain pad material.The fluid has nothing to do with touching the disc, so dont know why it would matter.

I am going back as much original as i can on my z.But the rear signal lights are mounted to a nice luggage rack.It bolts to several places, is very sturdy.But I want clean.I am taking it off.Where were the rear signals mounted.The pics of z bikes have a rear tailight cowling with the tailight built in.But my aircleaner opens on the left, and the battery is on the right, all z trademarks.I am not going to waste time looking for a cowling.I have 3 sets of pipes.2 4 pipe sets, and the original 4 into 2.I posted pictures of the one header and muffler i took off last night.Totally utterly destroyed by rust.I think I can salvage 4 headers.Then somehow manage to get either 2 or 4 mufflers attached from somewhere.Maybe jc whitney megaphones.I dont want to spend 400 for a mac.

I was so happy to find the z seat and have it on.

One very smart member said to count on removing the head,  How will I get this engine torn down if the pistons rings are seized? Does partzilla or z1 enterprises or someone still make rings? With 17,000 miles i doubt it needs bored out.never used a micrometer.I see hones that mount to a drill.I guess you open it up to fit your bore then go up and down removing minimal material? Is the goal to create crosshatches? For new ring adhesion?I never once honed a motor on a truck or car. I could take the block to a machine shop, perhaps they would know how to hone a 37 year old jap motor.My manual says do not remove the carbon ridge at the top of the bores.Why? Why hone if one isnt going to do that?

Rotating the engine is necessary to get the cam loosened, to give slack to the chain.So the motor will not budge.So once i figure out how to get the head off,the the cylinder base , then the motor should turn over.Unless the gears are rusted and frozen, or the clutch discs are frozen together. That is why I am leaning towards engine #2 or # 3 to use.
  This is a pain in the ass, but I bought it messed up on purpose, to rebuild, to learn these bikes so I am  still really enjoying this.

[crusierlover]

I figure rather than cut the chain to get the head off or whatever else, like you said replace it anyway due to the rust,sitting for 12 years.Once I split the cases I may find I have a 150 pound paperweight.I am glad to have extra parts.If the atf acetone is used, which i am going to do, how much, about 2 ounces down each sparkplug hole? Even if the motor unlocks, many guys said here they did theirs that way, got the frozen pistons moving, rode several thousand more miles.I dont expect to be that lucky.If I rebuild and put all solid good parts I expect the motor to last indefinitely.I figure the primary chain is toast.It looks like an orange bar right now.No matter how long it soaked I wouldn trust it to rev up to speed and stay together.A masterlink chain is a easy replacement, and if the motor had no issues I would do that.But since this is a can of orange worms I intend once the cases are split to replace the cam chain,primary chain,rings,circlips,seals,o rings and all.This bike is not worth much even in pristine condition.But it is a great learning tool for me.I dont need this bike for a daily rider.I love its potential.

[crusierlover]

Problem is whichever ones are at tdc or bdc is where they will stay until freed up.so 2 holes can hold a lot,2 can't

[SOHC4 Cafe Racer Fan]

That is the dilemma. Shame they can't all stop mid way up... You'll find the bores at BDC are the stuck ones anyway. So they hold the most and need the most.

If you pull the head and can't get it unstuck, BBQ it (motor free from frame and away from anything combustible)

Where are the smores?

[crusierlover]

um, may I ask....Are you guys kidding? You didnt do that to get the pistons unstuck for real did you? You just did it to get rid of it.Aluminum can never be used if its heated up that much.

The cylinder block feels like steel, the head and cases are aluminum.One might ask why not just go ahead and pull the engine now? Well, because being stuck has some advantages.If it were to break loose i can apply the brakes or pop it into gear to stop the engine turning over.This frozeness also helps break loose some of the larger bolts,rotor, etc. I really think the clutch is stuck, the primary chain is rusted like an iron bar, and the rings are stuck.2 of those are easy to remedy.

If I do have to trash a block I am going to get it sterile clean, then try to find plastic containers to fit each bore.Then at a backyard barbecue-this is texas-have one bore filled with my famous salsa,one with guacamole,one with barbecue sauce,one with frijoles.2 of my friends have entered and won prizes in cookoffs for beans and ribs.Combine that with shiner bock and country music, a few friends, you got yerself a shindig.

[754]

Cast iron liners,easy to replace. If you wreck one..
Just how hot did you think it would be getting when it is running?
Aluminum has some amazing properties sometimes..

[crusierlover]

I am not kidding. And aluminum takes a lot of heat (+1,200*) before it melts. The fire is within the steel liners anyway. It doesn't get as hot as you think. Hopefully, such an effort won't be required on your end.

By the way, I used SeaFoam to BBQ my cylinders. It is flammable but doesn't have the same combustion behavior as fuel.

yum.barbecued honda with seafoam sauce.

[crusierlover]

Cast iron liners,easy to replace. If you wreck one..
Just how hot did you think it would be getting when it is running?
Aluminum has some amazing properties sometimes..

  most bikes I have seen very few have thermometers, but usually the cylinders get about 450-500,not 1200. But,hopefully it wont come to that.One good thing today, my wife says if i can get rid of all the junk in the storage shed, which is a lot, i can use it for my shop.16x20 metal building with some shelves in there already.Quite motivating for me.

[crusierlover]

Just took a closer look at the license plate on the bike.I thought it said 04.Sat for 12 years.nope.It says 84.Sat for 23 years.Yep, I figger i will have a few parts rusted out.

[754]

Exhaust port is way over 1200 degrees, I think ... And piston crown near that..

[crusierlover]

Exhaust port is way over 1200 degrees, I think ... And piston crown near that..

wow.I had no idea.

[crusierlover]

Once I start taking this thing apart, it is crusted by decades of dirt and crud, what is best for some of the engine parts like the valve covers,center and right and left to soak in.Many articles I have read says after lapping valves, honing cylinders, etc clean in solvent.I am going to use berrymans on the carbs, but will chemtool clean junk off other parts without harming it.I know to avoid rubber, painted parts.Also, I do not particularly like painted engines.That is not original.I might change my mind after trying to refurbish some of this stuff.But on like the valve covers, engine cases, do ya'll take like mothers aluminum polish, hand rub it, use a polisher attached to a drill, or what?

[754]

If it's a cb 750 the crankcase, head and cylinder are all painted.. The outer covers are also fine brushed finish, and then clear coated..

[crusierlover]

If it's a cb 750 the crankcase, head and cylinder are all painted.. The outer covers are also fine brushed finish, and then clear coated..

no,mine is 79 650z

[crusierlover]

took the chain cover off, the primary sprocket, and inside the cover was 37 years of dirt and spiders nests.man this project is a huge one.

[crusierlover]

OK.Getting these carbs off has been a major pain so far.I have loosened all the screws in the clamps from the carbs to the head, and in the clamps on the back of the carbs between that and the airbox.The manual says slide the airbox back to give more room.After i disconnect the cables it does not look like the airbox is going to move anywhere.How much room are we talking about creating, an 1/8 inch?

[grcamna2]

I think removing all the clamps will help to get those boots to flex more if you decide not to cut the boots yet.

[crusierlover]

I think removing all the clamps will help to get those boots to flex more if you decide not to cut the boots yet.

the boots I can see look in very good condition.And they cost a lot.I am not going to cut them.

[rb550four]

Are you going to paint the frame ?  just asking... anyways,  the carb issue, You could take the battery box out ,remove the chrome half of the rear fender, then the shocks , lift it up then remove the inner rear fender and air filter box ,and then the carbs should have plenty of room .
  The rubber connections...You must back out the clamp screws  fully, put your finger on the backside of the screw to be sure they are unscrewed just ready to come out ( can't just loosen them  a little , won't work). hit them with a hair dryer on hot till they get soft...just a few minutes each and they should come off no problem. Use hairdryer again while re installing them and when re installing the carbs into them...way easier , less PITA , and the softened rubber probably won't tear.
  I use mothers for the shiny bits as a finish polish.  for the time encrusted bits  I use a soft wire wheel on a bench grinder to blow through years of oxidation first ,then use buffer wheels on a different bench grinder and use black,white and sometimes green  compound, I find the rouge to be greasy burns,and is harder to get off than the other polishes. Some guys use a bunch of different sand paper grades ...by hand then buff. I think life is too short to be doing that, but to each their own.  I have found that the 650 shiny bits especially up top don't polish as easy or as nice as let's say the 550 parts do . Don't know why , but they just don't buff out clean and is always lighter in luster.

[crusierlover]

That is great information.I have to remove the rear wheel,swingarm also to get the primary chain out.The bike has sat since 1984, I thought it was 2004.I am about 90% sure i will be using one of my other 2 engines.But once this one is out i will still try to unlock it.I am not going to use a masterlink chain.these bikes are lowtorque and high rpm.I dont want a chain flying apart.chains seem to range from about $70 to over 200.I will get a used chain for about $75.Maybe o ring.I doubt I will pull the shock and fender but the battery box is barely in the bike so I may do that.Your advice is always so good.I appreciate it.

there is a product made by KBS for frame painting.It brushes on,looks like powder coat when finished.

[crusierlover]

http://www.jegs.com/p/KBS-Coatings/KBS-Coatings-Frame-Coater-Kits/1044197/10002/-1


enough to do 5 bikes probably

[crusierlover]

I am thinking about going with my 80 model now, using the 79 for parts.why? Because:
1.I have the title to the 80.
2.I have 20 80 engines, that turn over easily complete with carbs
3.The 80 already has a good front tire,and functioning brakes.
4.The reg/rectifier,solenoid,mainfuse are off the 80,but in a box.It looks like they all mount on the left,on the 79 its on the right.I have the solenoid and r/r in a box.
5.It has functioning brakes
6.It last ran and was titled in 2014.
7.I think I could part out the 79 to pay for fixing the 80.
.I have another 80 engine that also turns over, it has been in a garage, the carbs off, and all the head openings on the carb mounting points have been taped and sealed over to prevent water getting in the motor.

cons:
1.The handlebar controls are not on the 80(oops, yes they are).The ones on the 79 should transfer over.The throttle cable is there on the 80,just not connected to a throttle sleeve/handgrip.
2.Dont know where the disconnected components go.I have a manual,perhaps it shows there.It shows the 79 r/r placement,not the 80 model(oops,yes it does).The turn signals are off the 80 model.I was going to leave them
off.The headlight is missing, but all the connectors hanging out of the bucket are intact.My 79 sat in a garage for 23 years.
3.I do not want to open a can of worms on the electrical stuff
4.I feel defeated.But I think the 80 logically makes more sense.


I just studied my manual.The r/r mounts the same, the instrument panel,blinker connections,headlight ,handlebar controls, all the same.The battery,main fuse,solenoid are on the right on the 79,on the left on the 80.I am not sure how to lengthen the wires to reach from the right side mounting of the solenoid and main fuse on the 79 to the left side location on the 80,but its only about 8 inches.Since the starter is on the left already the stock wiring might reach from the right to the left side.I wish I was doing mechanical and not electrical right now.

[crusierlover]

pics of 80 starting point.I tried posting multiple pics,clicked on more atachments.perhaps the files are too big.

[rb550four]

Okay, I have to ask, how does one get 20 1980  650 engines that turn over with carbs? Mistype? Hope not, very impressed , now here's a guy determined to have enough parts to finish a project before he even starts.Good show. Hey ,even if it is a typo and you have 2 engines to play with...that is a really decent start too.
 I'm a fan of the 80 650 for suspension and horsepower reasons ,a fitting upgrade to the 550, but love the classic looks of the 79 even though it handles more like a  750 . Torn really. You shouldn't have any trouble parting the 79 out, but you may kick yourself about it later, after the bug really sets in and you realize there's no stopping it.
 Do you have an 81 custom with dual front disc brakes? Just asking, don't need another one.
  I'm watching your threads closely, lots of parts, lots of questions, lots of interest, and no fear....yeah, you've  been bitten. I think we're seeing another collector blooming. It's an interesting phenomenon that happens allot around here.

[SOHC4 Cafe Racer Fan]

Okay, I have to ask, how does one get 20 1980  650 engines that turn over with carbs? Mistype? Hope not, very impressed , now here's a guy determined to have enough parts to finish a project before he even starts.Good show. Hey ,even if it is a typo and you have 2 engines to play with...that is a really decent start too.
 I'm a fan of the 80 650 for suspension and horsepower reasons ,a fitting upgrade to the 550, but love the classic looks of the 79 even though it handles more like a  750 . Torn really. You shouldn't have any trouble parting the 79 out, but you may kick yourself about it later, after the bug really sets in and you realize there's no stopping it.
 Do you have an 81 custom with dual front disc brakes? Just asking, don't need another one.
  I'm watching your threads closely, lots of parts, lots of questions, lots of interest, and no fear....yeah, you've  been bitten. I think we're seeing another collector blooming. It's an interesting phenomenon that happens allot around here.

RB,

You bring up some valid points. Maybe you should build a Frankenstein-650 with all the good parts.