Jump to content

535s front cylinder fuel leak


Tom Chapel
 Share

Recommended Posts

Hi all, I have fuel leaking from front cylinder and bike won't start.

I have spark at both plugs, fuel pump kicks in and shuts off as normal, carbs recently rebuilt with full Jadus kit.

Could it be the igniter unit?

Any useful advice gratefully received.

Ta

TC

Link to comment
Share on other sites

Do you want an ad-free experience? Join today and help support the Yamaha Owners Club.

Hi Tom, It's always difficult to tell what a problem is without seeing it! A few photos or even better a video of the problem makes it much easier. Just a few questions tho. Do you have a manual? are you sure that the new carb kit you have fitted is not the problem? usually when a bike is running well and you fiddle with it and then you get problems it's the bit's you fiddled with that caused the problem. Just sayin!

Link to comment
Share on other sites

  • Moderator

How would fuel leaking be down to the ignition circuit...🙄

Fuel issue is down to the carbs, something is off, with carbs it dont need to be by much.

Link to comment
Share on other sites

Thanks for the responses. I do have a manual and I have read it but am still unsure.

Bike is currently at the paint shop, the owner is a friend, and they have done the carbs there as the bike has had a full strip down to bare metal.

I suspect Cynic is probably correct and that there is an issue with the carbs. After talking to the shop yesterday though I was left with the impression the carbs were ok and that the igniter unit might be the issue, hence the post.

I don't get the bike back for a fortnight so I've asked them to bring it back as is and I'll sort it. Guess the first thing will be to check the carbs.

Am I correct in thinking that if the igniter unit was faulty then there would be weak or no spark?

 

Link to comment
Share on other sites

If it was running when you took it in, the place you took it to re-built the carbs, fuel now leaks from the carb feeding the front cylinder then I would suggest to you that the person who undertook the carb re-build has an obligation to correct the leak and get the bike running

  • Thanks 1
Link to comment
Share on other sites

1 hour ago, neversaydie said:

If it was running when you took it in, the place you took it to re-built the carbs, fuel now leaks from the carb feeding the front cylinder then I would suggest to you that the person who undertook the carb re-build has an obligation to correct the leak and get the bike running

Just need some mechanical advice, not business advice but thanks though.

It's not as straightforward as that anyway, they have gone way above and beyond for me on this build, the bike looks incredible, and as I say the owner is a friend. I'm not about to fall out with him over a cup of spilt petrol after the hours he's put in on this for me.

Anybody else have anything practical to offer regarding the igniter question?

cheers✌

 

Link to comment
Share on other sites

On 4/16/2022 at 5:32 PM, Tom Chapel said:

Hi all, I have fuel leaking from front cylinder and bike won't start.

A cylinder is a big thing, with many sides and holes. Where exactly is the fuel leaking from?
Through the head gasket? Through the rocker gasket? Through the carb/cylinder union?
There are not many places (or reasons) where fuel should ever be able to leak from, and you're not giving us much idea of which one it is.
Do both cylinders have good compression?

On 4/18/2022 at 10:42 PM, Tom Chapel said:

Just need some mechanical advice, not business advice but thanks though.

Seems a little rude, but that WAS the best mechanical advice... Only the bloke 'wot done it' will easily figure out what he's done.
The second best mechanical advice in this case is: If you don't know about fuel systems, don't mess with them! Leave them to the professionals.
If it was a professional that messed it up, then... If you're not going to take it back to him, a better professional would be a good idea rather than trying to tackle it by yourself (because, if YOU were a professional, you'd have done it yourself in the first place...).
If (as an amateur) you do anything to this then you run the risk of making whatever he has messed up worse (or simply giving him the option to say 'you must have done that when you took it apart') and then it will cost you twice as much to have it fixed properly.


If not caught (or a little less severe) you could have seen this problem on the road as all that great work on your bike went up in flames! And no body likes that idea..!!!

 


Something isn't right here...
You said the bike is currently in for paint.
And that your painter buddy has 'done your carbs' because it's had a full strip down.

You're not due to get it back for a fortnight (assumedly because it's still in paint), but you already know there's a problem with the fuel system, which means they've had the engine running? On a bench?
But you're going to get them to give you it back early so that: You can fix it? Isn't this what they were supposed to be doing?
What am I missing here? The timeline seems skewed somehow? Or is it just late..?

 

The bottom line here is: We need much more information!


1/ Did it leak BEFORE he took it apart?

2/ The other cylinder doesn't leak, does it fire?
3/ Do you have good compression on both cylinders?
4/ If you've had fuel leaking into your cylinder from 'possibly' a badly done carb, have you blown the head gasket through hydraulic lock while turning it over?

5/ Have you got any fuel in your engine oil?

6/ Did you notice there was a New Members Welcome Area?

7/ Has the rest of the engine been stripped?
8/ Exactly how much fuel is leaking?

9/ Photos/Videos are good!!!

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

 Share

×
×
  • Create New...