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Discussion Starter #1
Hello again!

For those of you who have followed my saga through the terrible year of 2009, I think it's time to put Vanessa down for some serious work :(

I've been fighting with the carbs since I put the V&H Cruisers on back in September (the soap opera that was 55 days). She's had trouble breathing properly since that whole debacle. I've done the smoke test to check for exhaust leaks and have found no indication of that being the issue. I decided I was going to rip the carbs off and rebuild them, but I just couldn't do it until the snow hit or until I was absolutely forced into it. Well, sad to say, I think that time has come.

Last night I took her out for a ride up to the pub to celebrate the passing of a wonderful woman- the turn out was awesome as there was standing room only in the bar as we walked outside to release memory balloons into the sky. Well, as I pulled out of my neighborhood, Vanessa started huffing and puffing like she was out of gas. As I sat at a light and played with the idle screw and throttle, she sputtered more and more until she stopped completely. Well I pushed her onto the side walk and mucked with the petcock, making sure it wasn't off or in reserve. Once I verified that, I tried to fire her up again and she wouldn't start. Then I threw the choke into full position and she started just fine- more indication there are some serious carb issues going on. Well I rode her to the pub to spend some time with friends then home again with no further issues other than minor popping and some mild sputtering.

This morning I brought her out into the sun to warm up when I started looking her over really good. To my horror, I now see she has some sort of an oil leak, though I'm not sure where it's coming from. It makes me want to tear her down that much more to make her whole again. The only problem is, as most of you who read my posts probably know, I have nearly NO mechanical knowledge. I'm hesitant to tear her down because I'm afraid she might not come back to life after. However, I refuse to take her to a shop as my last experience with doing so was so unpleasant I vowed it to be my last.

So I appeal to the good people of this forum for guidance and advice. I'm prepared to buy whatever tools will be required, though I have a good start so far. I think the time has come to put her in the man cave for the winter and tear her down. I want to remove the airbox (for an ear shave), the carbs (for a complete rebuild and possible re-jet), and possibly the motor to address the oil leak. I started to do this a week or so ago before I decided I couldn't sacrifice her to the work- I just had to get a few more miles in before hand, and now it seems impossible to postpone any longer.

Here is my starting point and the questions that follow. I'll appreciate any feedback you might have:

1) In pulling the airbox, is there a way to do this without pulling the engine completely or destroying the parts?

2) Is it possible to pull the carbs without removing the airbox? My hands are quite big and everything is packed so tightly in there I can't see a way to do so on my own.

3) What is the "best" way to detect the root cause(s) of this oil leak?

4) Anyone who has gone through rebuilding these things, can you offer some tips, advice, or even a "what to expect" list? I'm about to turn this into my primary project as I go on the hunt for a new bike. I'm gonna keep this one, but I need something reliable in the mean time.
 

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Concert connoisseur
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2,231 Posts
where does the oil seem to be leaking from. mine was in the front up over the oil filter, almost looked like it was coming out of the cylinder head. it trickled all the way down and dripped off the bike on the left side when parked back behind the shifter. it was a five minute fix and cost a buck or two for both cylinders as it was just the spark plug tube overflow. hopefully yours is the same location with all the trouble your having.
hope you get her all worked out by spring!
 

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Discussion Starter #3
There appears to be coming from the rear cylinder...

It seems to me that the cylinders are divided into a few different sections, each with a black rubber gasket between them. The top of the cylinder seems fine, but the middle joint seems to have some remnants of oil dripping down the side. More worrysome is the oil that seems to be fairly fresh at the middle of the V, and on the bottom of the engine (which is how I noticed it- there were 2 drops of oil on the floor this morning, something that this bike hadn't done before now).
 

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Adventuregeek
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162 Posts
Hey, you sure you don't have a stuck carb float? That's exactly how mine was acting when the rear float was stuck wide-open. It dumped tons of fuel into the cylinder which washed past the rings into the oil. I had what looked like oil - but was oil-soaked gasoline - leaking from the exhaust-to-head joint. It was dribbling oil about where you describe, though it did most of the actual leaking while running. While running, I got a lot of smoke out that exhaust pipe, as the extra gas and oil burned off.

If it's only a stuck float, there's a bag of easy tricks you can try without pulling the carbs. Otherwise, best of luck, and I hope you get your ride running happy soon!
 

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Discussion Starter #5
Good suggestion..

I'll look for these tricks unless there is anything in particular you might suggest to try. At this point I'll try anything :)

I'm hoping to snap some pictures today but work and garage cleaning will take up a majority of the day... I would like to use the Akem's Razor approach and start with the path of least resistance. While I don't really WANT to do it, I'm not opposed to tearing down the whole thing and rebuilding... it's just totally new territory for me so I'd like to wade in slow.
 

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Simple Solutions
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965 Posts
Hello again!


1) In pulling the airbox, is there a way to do this without pulling the engine completely or destroying the parts?
not that im aware of... i got mine out with an engin pull ....
2) Is it possible to pull the carbs without removing the airbox? My hands are quite big and everything is packed so tightly in there I can't see a way to do so on my own.
take a wood handled hammer or equivilant and pry the sir box up for a little more clearance... now the carbs are tight in there and even tighter with the airbox but they can be removed with the box in place.... paitents losen the boots and i use a pry bar to pull the carbs off the cylinders .... pop the throttle cables off the bracket on carb... but leave them connected to the carbs till they are out its easier to connect and disconect when they are out ...
disconect the choke cable , rotate and twist the carbs out ... disconect vac lines ....

3) What is the "best" way to detect the root cause(s) of this oil leak?
u say it apears to be seaping from the headgasket ? into the v between the cylinders.... best way to detect is with a dye in the oil but i always give the motor a good cleaning then drive and see where the highest point of oil... if u are noticing between the cylinders then i would look at the oil line that connects to the inside of both cylinders ...

4) Anyonewho has gone through rebuilding these things, can you offer some tips, advice, or even a "what to expect" list?
do one side at a time so u can have a templete to put the first side back together ... bike carbs are pretty simple (in comparesion to automotive less parts ... ) for the jets to clean them the best way to get in the little hole is with an old strand of throttle cable ...

I'm about to turn this into my primary project as I go on the hunt for a new bike. I'm gonna keep this one, but I need something reliable in the mean time.
take lots of pics and keep us informed may not need anyparts but a true rebuild would include replacing all the rubber ... if a float neadle is bad those wold have to be replaced as well
 

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Adventuregeek
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162 Posts
Here are the tricks I used to free the stuck float (just in case that's what's ailing your ride) They're all on the forum, but here's a summary.

Trick 1: Shut off the fuel valve and open the stuck carb's bowl drain screw to get the gas out. Take a can of carb cleaner and stick the jet spray tube up the drain tube. Squirt carb cleaner up in there until the bowl fills, wait a few seconds, let it drain. Repeat that a couple times, then close the drain screws. (a piece of aluminum foil will make a nice drain chute to keep carb cleaner from getting all over your engine).

Trick 2: Bang on the carb bowl with a screwdriver handle or other semi-soft implement. Sometimes it unsticks the float. You'll do this one periodically as the day goes one. More hits are better than BIG hits, DON'T break anything.

Trick 3: Dump Seafoam into the tank, 1:1 can:tank ratio. My tank was half full, so half a can went in. Now time to open the fuel valve, crank it over and let the solvent-loaded fuel into the carbs. Shut it off and let it sit.

Every half-hour or so, bang on the carbs again, then run it for a minute to get fresh solvent/fuel into the carbs and past the float valve. It may clatter and rattle a bit, since the gas-soaked oil isn't lubricating right.

If that's your problem (big if...) and you're lucky, it will start running better after a few spells of hammering and soaking. I harassed mine all day as I was working outside. Once you think it will run reasonably well to drive, change the oil and filter. Now drive it and let the Seafoam flowing past the valve finish cleaning it up. You'll get smoke out that exhaust pipe until the oil and gas burn off. I started my ride with the rear pipe still smoking, and a 50-mile ride later it had cleared up totally.

Whatever it is, I hope it's something easy and you can ride again soon. Good luck!
 

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Premium Member
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3,027 Posts
I had a stuck float on the rear carb on my '93, I got it unstuck several times without having to remove the carbs, but it would always stick again. I finally removed the carbs, and found a piece of flashing on the float that was hitting the inside of the float bowl. I sanded it down, put it back together, and it worked fine thereafter. This was during the warranty period, but I wasn't about to allow a dealer to work on my bike.


Don't be in a rush to remove the engine. There are several possible causes for an oil leak that can be dealt with without removing the engine. The best way to find where oil is coming from is to clean off all the oil with spray carb cleaner, let it dry, then spray some type of antiperspirant that dries white on the general area where the oil seems to be leaking from. Start the engine, and let it idle. The tiniest bit of oil will show up very clearly. There are 2 places I would check first. One is the cam chain tensioners, the other is a cap just below the spark plug, right side in the rear, left side in the front. There are o-rings behind these plastic caps.


If you find the leak is coming from some place that would require engine disassembly to fix, consider how bad the leak is, and whether you could get away with sticking a paper towel or rag somewhere to soak up the oil, and just let it leak, unless it is leaking badly enough to cause a low oil level in a short time.


The Vulcan engine is extremely complicated, with 4 cams, 4 cam chains, 4 cam chain tensioners, and a lot of guides that go with them. If you have the Clymer manual, read the entire engine section several times, look at all the pictures and drawings, and if you have any real doubts about your ability to do the job, don't. I am a professional auto mechanic with 32 years of experience, have built several car engines, including race engines, and also worked on several motorcycle engines. I would totally dread to tear into a Vulcan 750 engine. I'm sure I could do it, but it would be tedious and frustrating. I definitely wouldn't recommend someone with limited mechanical skills try it. Jerry.
 

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The Professor
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3,147 Posts
Four tensioners?????? where's the other two?? :confused:
Actualy there are four fixed tensioners and two automatic tensioners. Two at the bottom chain guide, two at the upper chain guide above the ACCT and the two ACCT's. :beerchug:
 

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Registered
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686 Posts
Hello again!

For those of you who have followed my saga through the terrible year of 2009, I think it's time to put Vanessa down for some serious work :(

I've been fighting with the carbs since I put the V&H Cruisers on back in September (the soap opera that was 55 days). She's had trouble breathing properly since that whole debacle. I've done the smoke test to check for exhaust leaks and have found no indication of that being the issue. I decided I was going to rip the carbs off and rebuild them, but I just couldn't do it until the snow hit or until I was absolutely forced into it. Well, sad to say, I think that time has come.

Last night I took her out for a ride up to the pub to celebrate the passing of a wonderful woman- the turn out was awesome as there was standing room only in the bar as we walked outside to release memory balloons into the sky. Well, as I pulled out of my neighborhood, Vanessa started huffing and puffing like she was out of gas. As I sat at a light and played with the idle screw and throttle, she sputtered more and more until she stopped completely. Well I pushed her onto the side walk and mucked with the petcock, making sure it wasn't off or in reserve. Once I verified that, I tried to fire her up again and she wouldn't start. Then I threw the choke into full position and she started just fine- more indication there are some serious carb issues going on. Well I rode her to the pub to spend some time with friends then home again with no further issues other than minor popping and some mild sputtering.

This morning I brought her out into the sun to warm up when I started looking her over really good. To my horror, I now see she has some sort of an oil leak, though I'm not sure where it's coming from. It makes me want to tear her down that much more to make her whole again. The only problem is, as most of you who read my posts probably know, I have nearly NO mechanical knowledge. I'm hesitant to tear her down because I'm afraid she might not come back to life after. However, I refuse to take her to a shop as my last experience with doing so was so unpleasant I vowed it to be my last.

So I appeal to the good people of this forum for guidance and advice. I'm prepared to buy whatever tools will be required, though I have a good start so far. I think the time has come to put her in the man cave for the winter and tear her down. I want to remove the airbox (for an ear shave), the carbs (for a complete rebuild and possible re-jet), and possibly the motor to address the oil leak. I started to do this a week or so ago before I decided I couldn't sacrifice her to the work- I just had to get a few more miles in before hand, and now it seems impossible to postpone any longer.

Here is my starting point and the questions that follow. I'll appreciate any feedback you might have:

1) In pulling the airbox, is there a way to do this without pulling the engine completely or destroying the parts?

2) Is it possible to pull the carbs without removing the airbox? My hands are quite big and everything is packed so tightly in there I can't see a way to do so on my own.

3) What is the "best" way to detect the root cause(s) of this oil leak?

4) Anyone who has gone through rebuilding these things, can you offer some tips, advice, or even a "what to expect" list? I'm about to turn this into my primary project as I go on the hunt for a new bike. I'm gonna keep this one, but I need something reliable in the mean time.

Your answer may be in this thread:
http://www.vn750.com/forum/showthread.php?t=13383
 
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