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Discussion Starter #1
Hi Everybody,

This is my first post, but here goes. I bought a 2002 VN750 about 5 weeks ago with 20k miles on it. It had a few scratches on the tank, but other than that it didn't appear to have been laid over or have been left outside. It seemed like a pretty good deal so I didn't have any issue with purchasing it for $1400.

I've been driving it every day to my university without issue. I mean, it is kind of hard to get into second gear sometimes as it seems to like neutral and it had a very quiet tick (which I later found out it is likely the ACCT or maybe just natural valve ticking). Other than that it's been reliable. However, yesterday was the first time I got to take it on a somewhat lengthy cruise, and after about an hour I started getting a very loud knocking sound in what appeared to be the top back side of the rear cylinder.

I immediately pulled over and killed it, checked the oil, and made sure there was still coolant or overheated. Everything appeared to be OK, but but when I started the bike up again the ticking was still there and it changed speed with RPM. I was only about 5 miles from home when it happened, so like an idiot I decided to chance it so I cruised back at about 20 mph in 4th gear to keep the RPM's as low as possible.

About a mile from home it made a single pop and the engine instantly died. I don't know if it was hard enough of a seizure to lock the back tire or not because I pulled in the clutch and coasted it to a side street. When on the side of the road I tried to see if it would turn over but all you could hear is the starter tick and something in the engine tick with the starter so I assume it was hung up on something.

My question is this: I know there are a million possibilities that could have caused this failure and it's impossible to know what without tearing into it, but if the ACCT failed, would it cause a hard seizure like that? I'm going to have to tear the engine apart regardless but I'm trying to figure out the likely candidates beforehand. I was also wondering if there are any write-ups on taking the engine out and rebuilding it like there is on the rear spline lube/replacement thread.
 

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If the ACCT goes bad enough for the cam chain to say, jump a tooth, you can have the piston hit a valve before it closes.... And real bad things can go wrong ... Mike from the big easy had this happen on his FJR... It can happen on the Vulcan too...

There of course are a few other bad things that could have gone wrong...but won't be obvious untill the motor is opened up.
But from your post it sounds like a sucked valve to me......


KM
 

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Linkmeister Supreme
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The Reanimater
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Pull your spark plug then remove (can't think of the name right now) the pipe deal in where the spark plug goes. With that out you can see if your cam chain snapped/Broke.
 

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Discussion Starter #6
Thanks for the advice, Everyone. There is another issue where the bike seems to prefer to go to neutral when shifting from first to second. If I have to tear this engine apart anyways, I'd like to fix whatever is causing that. I have seen several threads on the issue (positive neutral finder?), but I have not seen any with a lot of images like the rebuilt link posted by OlhossCanada.


ps, the 30 second wait between searches is super lame. haha
 

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Linkmeister Supreme
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I don`t recall seeing any pics of the PNF online. My Clymer manual has some pics of the 3 small steel ball bearings the ride in raised splines on the countershaft, and lock the 4th gear in place on the shaft. (Don`t ask me to explain why it`s 4th gear, I don`t know?? I`m just writing what I read.)

Get a manual with clear pics before dismantling the tranny.
Take several digital pics of the process and lay the gears/shafts/clips out in order in some egg cartons to keep parts in order for easier and correct reassembly.
 

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This kinda' poopoo gives me nightmares. I still have stock ACCT's, and now I'm scared to get her above 6k revs. Looks like I'm gonna have to get the stronger springs or MCCT's ... man .... :doh:
 

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Linkmeister Supreme
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Into the Darkness
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Thanks for the advice, Everyone. There is another issue where the bike seems to prefer to go to neutral when shifting from first to second. If I have to tear this engine apart anyways, I'd like to fix whatever is causing that. I have seen several threads on the issue (positive neutral finder?), but I have not seen any with a lot of images like the rebuilt link posted by OlhossCanada.


ps, the 30 second wait between searches is super lame. haha
With the bike going to neutral from 1st gear to 2nd gear that's because of the neutral safety switch in the bike. Mine does it quite a bit. It all deals with lower speeds. I figured to shift mine at 4k rpm and it 98% of the time doesn't go into neutral. Anyhow that isn't something to worry about as it is natural for the switch that is in our bikes.

Sorry to hear about the difficulty you are having with your bike though. That is a bummer.
 

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Discussion Starter #12
Well, I suppose this is my problem!

Who is a good retailer that sells pistons, rings, heads, valves, and the timing chain?







 

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cheapcycleparts.com, or ronayers.com are two pretty good retailers.
E-Bay is a good place to find cylinders and heads for good prices.
There is a link here on the site that is directly linked with E-Bay to look and see who has the parts you need.
 

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This is the second thread on major engine failures because of valves and pistons failing.
I'm really scared to tear mine down to see the damage that has been done to it.
If it is a major failure, then I'm going to part it out.
I will keep this forum posted as I tear it down.
 

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Look up sparkingdogg on e-bay. He is in the process of tearing down a vulcan.
He has several that he gets into his shop, and he told me he would sell me a complete engine if I needed one.
 

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This kinda' poopoo gives me nightmares. I still have stock ACCT's, and now I'm scared to get her above 6k revs. Looks like I'm gonna have to get the stronger springs or MCCT's ... man .... :doh:
Go the mcct route. I ordered and installed the heavier springs and was not happy. Did not make much difference. Wibs conversion works good.
 

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Discussion Starter #17 (Edited)
Ok, I ordered a Piston and Jug. Still looking on Ebay for a head assembly but there aren't very many at the moment.

I do have a question regarding the water pump. Should it wobble a little bit if you push on the impeller vertically or some other direction or should it be firm in whatever it is seated to? I can move it maybe 1/8" to 1/4"

Edit: Also, does anyone have pictures of the positive neutral finder? I'm trying to debate if I should crack the case open to keep it from sticking.
 

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Discussion Starter #18
So... you'll never believe what a small world it is, but last night on Craigslist I saw an add for an "2002 Vulcan 750" for $300 dollars. It was a salvage bike but the guy said the engine was good except the front cams were warn. I drive to go pick up the bike and it ended up being in the same town where I bought mine a few months ago. Long story short, after talking to the guy a while he mentioned that the engine was from an '02 (20k miles) and the frame was from a '99 (30k miles). He said he swapped engines on it with another bike because of the front cams. He said the owner that bought it from him (and the same person who sold it to me) was well aware of this. So I offered the guy 200 bucks and took the original engine for my bike home with me.

My question is this, if the guy I bought this bike from KNEW the engine was from a '99 with 30k miles on it and never told me about it when I bought the bike. Is he liable for this?

Hopefully I can play Dr. Frankenstein and make an engine out of these two, but right before I saw this bike on craigslist I bought a rear head and jug on ebay. So I may be selling some parts on here in a few weeks.
 

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I would think so, but you need to talk to a lawyer. Might cost you $50-100 to do so, but you might get your money back from the sale. Got any friends in the legal profession that can give you a bit of free advice before perusing this???
 

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Old Truck Junkie
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I don't think that there is any legal action on this as we buy this bikes used and as is.
 
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