Found a vacuum leak, first "major" repair ever, have a question...

[tasop7]

So, most people here would probably not consider this a major repair, but for me (who's most advanced thing done is an oil change), it is.

Here is my long and detailed story...

It all started with me wanting to sync the throttle bodies. I just bought a Morgan Carbtune Pro, had it delivered yesterday, and hooked it up today to sync the TB's. I was actually really excited to sync them, because it was my very first major adjustment to a bike as well. I've never been a mechanical person but have always wanted to learn about cars and bikes. Especially since I have the service manual available to me (thanks to this site :thumbup, it's really not that hard to follow instructions.

Anyway, so I got the Carbtune Pro all hooked up to the 4 throttle body synchronizing hoses, started the bike, and then immediate disapointment ! All the levels in the Carbtune rose except for the 3rd one... it didn't move one bit. My first thought was that the Carbtune might be bad, so to test it I switched positions 3 and 4... but now 3 rose and 4 was dead still on the Carbtune. So next and even simpler, I disconnected the Carbtune hose from the 3rd throttle body sync hose, and put my finger on it to see if I felt any vacuum pressure... and I sure didn't. I also checked to see if the hose had any kinks in it, but it was perfect.

At this point I really thought this was going to turn into a big project and that something was seriously wrong with the bike. My first thought was to run to this forum and frantically ask what could be wrong... but I stopped myself and said, "Ok, if you wanna learn about how this stuff works, then go learn how it works! " So I went through some basic logical troubleshooting. Not knowing much about engines, I thought maybe the 3rd spark plug could be bad or the 3rd cylinder isn't firing, etc... but all 4 header pipes were burning hot (and the bike didn't seem to be running all that bad to begin with). So I then went back to the syncing hoses and examined them closer. With a flash light, I followed the hoses all the way back under the air filter case, and just barely spotted the problem. It was a very tight and dark area, but it almost looked like there was a split in the hose. I then opened up the service manual to look up what was needed to take off the air filter case. When I took it off, here is what I found...

I cannot even begin to tell you how happy I was when I saw the split in the hose. I was just glad that it wasn't more of a major issue. So I just cut the hose where the split was, got rid of the split off piece, and reattached the hose... problem fixed! :thumbup:

I then put the air filter case back on, started the bike, and all 4 levels rose on the Carbtune. The bike definitely felt smoother without that leak as well (but I never had anything to compare it to before). By this time it was dark out and pretty late to be syncing the throttle bodies (I live in a townhouse so I didn't want to make too much noise). I'll sync them tomorrow, but one thing I did notice was that the 3rd throttle body level was definitely higher than the other 3 on the Carbtune when I started the bike.

So, my question is... Not knowing how long the bike has been running with this air leak, could this have caused any damage to anything, or just keep the bike from running as smooth as it can be?

Thanks for reading my story... I was so proud of myself lol!

 

[CZAR357]

Glad you found the problem yourself! I know I would have been if I were you! As for the question, Ill let someone else answer because I have no clue.

 

[Stumbles06]

So, my question is... Not knowing how long the bike has been running with this air leak, could this have caused any damage to anything, or just keep the bike from running as smooth as it can be?

Thanks for reading my story... I was so proud of myself lol!

Congrats on finding the problem.

As for your question, no harm would have been done by the vacuum leak, just engine running would have been crappy. Internals will be fine. :thumbup:

:rockon:

 

[Motogiro]

That's great that you found that. Think I'll check mine.

I had a vacuum leak similar to that but it was on my Jeep. I fixed the leak and noticed it would idle down very slowly when coming to a stop. I realize that my computer had learned and adjusted itself to run with the vacuum leak. I did a CPU reset and all was fine after that. Just in case you might do a CPU reset. I think all that is required is to unhook the battery for a few minutes and hook it up again. I also had a glitch that I caused on the bikes CPU and the bike wouldn't run and when I did the reset it started and has run fine ever since. Just a thought.

 

[jtarkany]

Well, gues I'll be pulling the airfilter box nest weekend and taking a look. Thanks for sharing :thumbup:

PS - While you are in there, you might want to do bd43's headlight mod if you have'nt already.

 

[tasop7]

That's great that you found that. Think I'll check mine.

I had a vacuum leak similar to that but it was on my Jeep. I fixed the leak and noticed it would idle down very slowly when coming to a stop. I realize that my computer had learned and adjusted itself to run with the vacuum leak. I did a CPU reset and all was fine after that. Just in case you might do a CPU reset. I think all that is required is to unhook the battery for a few minutes and hook it up again. I also had a glitch that I caused on the bikes CPU and the bike wouldn't run and when I did the reset it started and has run fine ever since. Just a thought.

I had to disconnect the battery to take off the air filter case. So the battery was unplugged for over an hour while I was repairing the hose and checking some other stuff. So if unplugging the battery for a little while resets the CPU, then I'm pretty sure mine was reset.

 

[FZ1inNH]

I had to disconnect the battery to take off the air filter case. So the battery was unplugged for over an hour while I was repairing the hose and checking some other stuff. So if unplugging the battery for a little while resets the CPU, then I'm pretty sure mine was reset.

Yup! You solved both issues at the same time!

Well done! It's quite a feeling to diagnose and repair something all by yourself. Great job man! :thumbup: