Hi Guy's, need help yet again! Fortunately it's my old 1999 GSXR750 SRAD (injection) that's the problem though. I have finally got her started after I think 7 years of sitting idle in my garage. I cleaned the tank out and fitted a new fuel pump as it was completely knackered and electrically shorting out. I took the spark plugs out and poured a little engine oil into each cylinder and let it soak for a week. I then turned her over with the plugs out to make sure she wasn't seized and loosen her up a little. Anyway, put the tank back with a little fuel (2/3 pints) and she fired up almost first time Awesome! Sadly though after a couple of minutes running the engine, petrol begins to leak from the bottom of the tank. It's definitely not from the pump gasket or any of the fuel pipes. Without the engine running the leak stops and I can't find where it is coming from.
Any ideas on how to find the leak? Perhaps I can pressurise the tank somehow? If I can find the source of the leak then I can hopefully seal it from the outside. Another option would be to use a tank sealant but how do I ensure the fuel outlets and breathers don't get clogged with the sealant? I am not sure there is enough access to cap off the outlets internally.
My final thought was to buy a replacement used tank but I can only find ones suitable for carburettor versions. It's only a tatty old track bike so I don't want to spend much more cash on her.
As always thanks in advance for any help which is very much appreciated.
If you don't have a compressor in your shed, you can use an old vacuum cleaner on blow to create a bit of pressure, just seal up the gap with something. I used closed cell foam, cut for a tight fit in the filler hole. I had a compressor though, but an old vac on blow would work too.
PS, it was on the boat tank, not the bike, much bigger tank at 270L.
Run the pump without starting the bike and see if it leaks, if not leaking when not running it sounds more like pump, hoses or fuel rail than tank
Hi Steve,
The pump initialises when first turned on at the ignition but how do you keep the pump running without starting the bike? Can I just apply +12V at the connector or does I need any other inputs?
Regards
Phil
Thank Col I don't have a compressor but can hook up a garden blower👍
Not sure, but maybe turn the ignition off and on a few times and check for leaks
🤣😂🤣 Sometimes the most obvious things just pass me by🤣😂🤣
Old trick to find leaks.
Take the tank off the bike. coat it with some talcum or baby powder.
Put the tank back on.
With the bike running, wait for it to leak then turn the bike off. Take the tank off and where there is wet powder, trace it and you will find the source of your leak.
Very clever Bluey. 👍 Dont know if anyone knows, to temporary fix fuel leak not under pressure, just use hand soap. Might get you home one day.
Thanks Blue that's a top tip mate👏👏👏👍
Quote from: Big Phil on Sunday, 01 November 2020, 05:37 PM
Thanks Blue that's a top tip mate👏👏👏👍
If you are just going to use some sort of fuel tank leak repair putty. I can recommend the Permatex one.
When I first bought my 1400, I ended up finding some pin hole leaks in the tank. Repaired the first 2 leaks I found with some putty and it worked fine and is stuck solid to the tank, even now, its still stuck on.
Only reason I ended up using a tank liner is because I then found the previous owner had already put a tank liner in the tank but did a crap job of it and it was flaking off in huge chunks. I documented it in my blog on this site. So ended up cutting the base out of the tank to remove the old liner and then had it soldered back in again by a car radiator place. Then put a tank liner through it.
Hi Blue,
That's great to know. My plan, one I have found the leak, is to use a putty on the outside of the tank and was wondering which type to use. I will look for the Permatex one. I did read your thread a couple of days ago on the tank liner you had to replace. That's another reason why I don't want to use one unless I have to as it can be a nightmare if it doesn't bond properly.
Thanks again mate very much appreciated
Phil
Phil,
Replace all your fuel lines, they perish and/or harden. One will be perished and you`ll not see it. I once had a similar problem with my GSX`R1100. New fuel lines sorted it. Good luck and keep us posted :cheers:.
Big Phil.
I just followed the directions to the letter on the KBS liner kit and it worked fine. Not had any problems since putting in the liner.
Previous owner just did a crap job of it and didn't drain out the excess liner fluid. hence it just congealed into the lower areas of the tank and eventually just started coming off in big chunks as you saw in my blog photos. Big Mess.
Just takes time and some patience to get the liner to coat the whole tank.
To get the small amount of excess out and also to coat the inner breather lines inside the tank, I used an old artists paint brush that I had (which I was happy to throw away afterwards). I just used the brush to coat the inner metal breather lines in the tank. Then used the brush to "scoop" up little by little the excess liner with the tank sitting upside down. Fuel filler on the ground and I was accessing the tank via the fuel pump hole and fuel sender holes. Slow process, but I got out most of the excess liner that way.
Just find the leaks and get them soldered up by someone that knows what they are doing, liner is last resort, but if it's a track bike that will probably be the quick fix.
First off a big thank you to all of you guys who offered tips and methods to find my tank leak. However, no matter how hard I looked and the methods I used showed a leak in the tank whilst off the bike. Today the sun was shining and it was a beautiful clear day. So I gave it one more shot and got the bike outside of the garage on the roadside. Now I wouldn't have to worry quite so much about setting the garage on fire with my house and worldly goods along with it. My idea was not to panic and immediately turn off the engine but have a decent look outside in daylight to see where the leak was coming from. First off I inspected the tank again and couldn't see any sign of corrosion or cracks that would cause a leak. I fitted the tank to the bike exactly as I have done numerous times before making sure the fuel pipes were very secure but this time I loosely bolted the tank down onto the frame, no idea why I just did. Started her up again and ran her for 10 minutes and not a hint of a leak. Now totally confused I could only think the bolts had grounded the tank to the frame. Without this ground path perhaps this had caused the injectors and fuel pump to behave erratically. So I removed the tank retaining bolts, started the engine again and within 60 seconds one of the breather pipes was flying around and spitting fuel everywhere. I therefore refitted the tank retaining bolts and all was well again. WTF 😳 but hey ho 🤔 you live and learn🤗🤗🤗
Is it possible that the pump and or injectors were spitting fuel out of one of the breather pipes due to the pump and injectors not being grounded together?
That doesn't make sense to me, the pump etc grounds via the loom to the tank not via the rubber tank mountings.
I'd suspect a split fuel pipe that opens up as you lift the tank slightly. I've had the small low pressure pipe from the swirl pot to rear of the tank split & it just dripped slighty, it did it all the time though.
I totally agree it makes no sense whatsoever but it's not leaking now. One thing to mention however the tank does make a ground to the frame via the bolts located nearest the seat on my SRAD. Still completely baffled. I have fitted new fuel pipes since finding the leak so doubt that's the problem because it continued after they were changed. Anyway, it is what it is for me. The leak has gone, the bike runs, I most probably missed a leaking joint or pipe, I honestly don't have a clue but I now have a leak free bike 🤗
Phil, good news - all positives, and you have established that it wasn`t your tank :)
It could simply have been a case that in repeatedly moving the tank around fuel was sloshing about all through the system inc the breathers. Now the tank is correctly positioned and bolted, you fuel lines are correctly routed etc. all will be well.
Give her a run round the block a couple of times, nobody will notice ;)....... :onya:
Your probably spot on with that analysis Dave. I would love to be able to run her around the block a couple of times but I have the chain and sprockets to replace, the brakes to rebuild and fork seals to change before she will be anywhere near safe to ride. Labour of love now she running though😍 She might be a decrepit old SRAD but she's given me so such fun in the past on track I can't let her rot away anymore. It's verging on criminal how I've neglected her over the last 7 years.😞