unseizing a VF500F

hi everyone

im new to this site and to Honda Vf and i suppose bikes in general.

a little while ago i brought a vf500f and a few other bikes in a group deal. i got 3 bikes for a steal but i couldn't get the Honda to turn over when i brought it. i believe it is seized, as i can get it to turn over no matter what i do and there was rust on the spark plugs when i pulled them out. i have put a few different types of oil into the cylinders to try and loosen them but i cant seem to figure out where i can get a socket onto the crank shaft to turn the bike over. i was guessing i would have to take the alternator engine cover than remove the flywheel. than i should be able to use a bolt to turn over the engine, is the correct. i know i should pull the engine out and get it rebuild but at this point in time the bike owes me no money so i just want to get it running, ride it and see if i like it. than spend the money fixing it right up.

any other help would be great too

thanks

 

84/85 model 500F's had "valve" issues. Most of those model engines had those issues at 20,000 plus miles. Do all four spark plugs have rust on them? Were the carbs off the engine? The bike stored outside? Fill each cylinder with Marvel Mystery Oil and let it soak for days. I have unseized a 500F engine by putting it up on the center stand and shifting the trans into 6th gear. (you'll have to turn the rear wheel several inches every time you shift) Grab a spoke on the rear wheel and pull hard in the same direction as the wheel would turn when riding it. Repeat. Sounds like your engine is seized up really good though. Mine was not. It only took 4 or 5 jerks to break it loose. If your bike is an 86 model you have better odds of not having "valve issues".
What does the engine oil look like? Is there obvious green coolant in it? Does it look like chocolate milk? Is the oil level at the full mark or above it? If the oil is "clean" that could be a good sign. Does the oil have a strong gasoline smell? (this would actually be normal if this bike has been sitting for a while without running)

 

On any engine that has an issue that serious it is best to disassemble and inspect rather than force it to try to turn over and just cause further damage.

 

Im with toe on this one. If it doesnt turn easily with the plugs out, even just a little, then you should pull it and disassemble the engine and inspect. Easiest way is to pull the heads and maybe the cylinders, try not to split the cases if you dont have to. If this bike dropped a valve and you force it then you can make any rebuild costly.

If you have a bore scope then you can do an inspection that way and make sure you look in both sided of the piston. Also look for broken bits in the oil. A broken gear can cause it not to turn. If everything checks out then use a very light oil or cutting oil to free the engine and tranny. I have used diesel fuel with success as it has some lubrication value. Do not use gasoline. That will make things worse.

Best thing, it owes you nothing, take it apart. If its too big of a job then sell as is.

 

the bike only has 20,000 km on it, so im hoping any valve issue has not had a change to happen yet. carbs are on and all 4 sparks where rusty

the bike will roll in Natural but nothing in any year. i have been trying to rotate it in a high gear but i will give it another go. i dropped the oil and it did have a slight brown tinge to it.

the guy i got the bike off said he was told it ran when he brought it but he never tried to start it and just left it fitting in his shed with the other 3 bikes. (he wanted him and his son to do them up)

i dont really have a lot of room to take the engine right out and pull it all apart and i wish i had an inspection camera because it would make this a lot easier.

what would you check and how would you check them

 

You can push the bike in neutral? Or crank the engine in neutral? Be more clear please.

If you can push but not crank then best guess is pistons and rings. Both of which you will need to do if its had water in it. Your plugs have rust so water was in it.

Have you proven the clutch yet? Put it in gear then pull the clutch in and see if you can move the bike. If you can then the tranny should be ok. If not then there is a bigger problem.

Stuck engines usually need to be taken apart, at least the heads off. A small amount of rust acts like a sand blaster on the pistons and rings. The oil trick is only to see if you can free it up before fixing it. A heat seized engine won't free up at all.

 

you can push the bike in neutral but it will no crank. i have tried the clutch and it does work (putting the bike in gear, pulling the clutch in and rolling the bike freely)

so how will i go about using oil to break the engine free to it can be cleaned (where can i put a socket on the crank or should i just keep trying to rotating the Tyre)

 

i brought 3 bikes for $700 and have sold the first two for $700 total. i was hoping to keep this bike as a second bike for myself. i want to give sport bikes a go as currently i only ride a cruiser. the big thing this bike has going for it is that it is LAMS approved (meaning novices can ride it, it would also be one of the most powerful LAMS bike you can buy). i would guess i could sell this bike as sits for around $500 if i had to guess but im hoping it doesn't need a lot of work ( it does need a new exhaust, new air filter cover and new throttle cable.) so than i would have something that was cheap that i would ride (and when its going, the last one i saw for sale had a bag BLUE paint job. double the km and they wanted $4,000 for it and it sold.

 

Get a can of SeaFome Deep Creep (penetrating oil) put a bunch in each cylinder through the spark plug hole, Let sit for a day or 3 then put the bike in 5th gear and rock it back and forth. Deep Creep is a rust eater and penetrating oil and is 5000% better then that WD40 crap.I've had stuff that was 40-50 years old free up that were completely frozen up with rust.

 

You're wasting your time with that engine, Bunky, as all sayin. I believe it's fair to assume nearly every VF500 engine you see out of a bike has issues by now. The few fine-running 500s are prized, and the others have stuck or damaged motors not practically repairable, New parts to replace old ones are mostly UNavailable, so a proper rebuild without new OEM parts is impossible, right ?:congratulatory: It's too bad more VF500s haven't survived the years and neglect that young riders do with their first bikes, cuz when they're good, the engine is incredibly SMMMMMMMMMMoooooooth ! A great bike when new.

(Now, i believe, just a few used, non-running 500s are passed hot potato-like, back and forth between younger, hopeful and dreaming and illusioned would-be riders, and older, disillusioned but wiser would-be riders of the VF500s of past dreams. It's never long before another hopeful guy discovers a VF500 under a porch, behind a shed, in a storage locker, in the back of a shop, neighbor's back yard, or parts in boxes that someone claimed was "VF-somethin"and stumbles here for advice, innit ?? Imagine every previous VF500 owner, likely now dead, addled, or in prison, most of 'em.)

*Piston rings and cylinders are ruined if they rust together, if that's why the engine locked up. Hondas usually have a small one-nut cover on clutch or alternator to remove for socket access for turning crank, and no oil will emerge to soil your ballet slippers.

 

I am thinking the bike had a blown head gasket and it's not worth messing with. A VF500F, not running is a real crap shoot. I bought one not running but I have a mental issue when it comes to lost homeless bikes. Tink said it best ". . . getting too close to a VF500 is like falling in love with a stripper."

Rust is not always a killer. I used to gently break Triumph engines lose by putting WD40 and 100psi air pressure on top of the effected cylinder. We used to see a lot of locked up bikes due to unvented driers in garages. I have never tried this on a V four engine. Is there rust on all the plugs?

 

yeah rust was on all the plugs.

thanks for all the info guys. i know this bike is 99% not going to be worth doing up but can we get back to the question. it will not cost me anything to try and unseize the engine and if its stuffed, its stuffed. at least i will know and i can sell it and tell the person the engine is stuffed. i cant break a broken engine. worse case i might rebuild the whole thing when i have more time. i like old bike and cars and love working on them (and i do know the painful trouble of falling in love with a stripper lol thats the idea. its looks good and feel great, but the second you stop giving it money it just stops. shit like sounds like most woman :glee

but can someone just answer this - if i remove the fly wheel than put the bolt that should hold the fly wheel on and tighten it back up, can and should i use that to turn the engine over. if not, how. i will try rocking the bike in gear at again to see if that works while i make a tool to take the fly wheel off.

 

Leave flywheel on and just use that bolt to rock the engine back and forth. As above wd-40 is junk. Its not a lube and not a cleaner yet has properties of both. And despite popular belief the wd does not stand for anything. Best to use either diesel fuel or deep creep down the plug holes. And fill the cylinders up as they have to break the rust on the walls off too. Dont worry about it going out the exhaust. It wont hurt anything. And go slow, those rings are garbage. If it does run you will tear the walls apart or wedge a piston. Both not good.
I used to get hard to find parts from a company in texas. Im not at home today/tomorrow but as soon as I can ill post there site address.

 

Rust on all the plugs? have you drained the crankcase and checked for dead fish? It could be a flood salvage bikes. It is was flood damaged then you really want to run. Electrical issues and corroded connectors are the hallmarks of bikes in standing water.

By the way, the trick is not the WD40. WD40 is crap. The trick is putting 100psi air pressure on top of the effected cylinder with WD40 in it. Believe me it works. I have never done it on a VF but I have done this on 4 or 5 Triumph twins. I would think it would work on a VF if you pulled the cams and got the valves closed.

 

Lots of flood damaged bikes floated around here after Katrina. They are huge trouble, almost as bad as a bike that has caught fire.