Post by: 110% on 18 April 2015, 12:10:17 pm
I had a problem just before winter with poor running on acceleration, and put it down to a faulty tps as I had the recounter fault showing with the counter flicking between 3 different positions. For about a year it was never caused a problem with the engine but in October with the poor running I decided to buy a second hand one and fit it to the bike. This didn't solve the poor running g on acceleration so I left it over winter and bought a brand new tps as the 2nd hand one also had resistances outside of the Haynes Manuel spec.
Having put the new one in yesterday along with a brand new air filter and new spark plugs, the problem persists. The engine idles with the choke on but when I open the throttle it stalls.
The vacuum of the carbs seems fine as I have a carb sync set, and there doesn't appear to be any leaks in the manifolds.
I think I know where my problem now lies, but I was hoping for some confirmation from people on here if you are kind enough to contribute to my problem solving.
Many thanks in advance.
Dave.
Post by: darrsi on 18 April 2015, 01:31:33 pm
Post by: Fazerider on 18 April 2015, 02:16:00 pm
Are you getting decent sparks? It's an easy check so long as you remember to let it jump to the cylinder head rather than the insulated cam cover. ;)
Check the fuel level in the carbs. If none of those show a problem I'd guess it's a case of getting the carbs off for a good clean/blow-though of the jets and passageways.
Edit: does it "get through" the rough running at higher revs? If not, a faulty fuel pump/clogged filter may simply be causing fuel starvation.
Post by: 110% on 18 April 2015, 03:50:26 pm
I was also thinking it might be the carbs need a full clean. All 4 cylinders are firing, so it's not the sparks or electrics.
I'll have to try pushing through to the higher revs. As soon as I was putting the throttle on it was instantly stalling.
(Fazerrider: The low voltage problem was solved by a new battery. This be has been expensive to maintain over the past few years!!)
Post by: His Dudeness on 18 April 2015, 05:20:36 pm
Post by: stevierst on 18 April 2015, 07:40:07 pm
Post by: 110% on 18 April 2015, 08:17:22 pm
I think I need to take the carbs out and see if the jets are blocked as I'm guessing if the idle jet is clear and air gets through with the choke open, but when the throttle opens it stalls, (and the air filter is brand new) it must be the main jets not supplying enough fuel.
Thanks very much for everyone's comments.
Last question before I take the carbs apart - are there any important gaskets/rings etc that need replacing on re-assembly if I'm stripping down the carbs?
Post by: anutz on 18 April 2015, 08:55:53 pm
see my question earlier this week...
http://foc-u.co.uk/index.php/topic,16590.0.html (http://foc-u.co.uk/index.php/topic,16590.0.html)
Post by: darrsi on 19 April 2015, 12:14:18 am
Post by: anutz on 19 April 2015, 08:06:16 am
Post by: darrsi on 19 April 2015, 08:40:40 am
if it is open could a blocked fuel filter cause issues - not sure what would block it up so bad?
If you've ever had water in your tank, via a leak around your petrol cap, then it's possible that rust could eventually clog up the fuel filter, but i would imagine that would cause below average performance rather than cutting out altogether.
Always worth changing though as they're very inexpensive and easy enough to fit.
Post by: Fazerider on 19 April 2015, 08:56:31 am
Carb gaskets: I've always been able to re-use the big ones that seal the float bowls.
I have had an O-ring that seals the brass needle valve body fail, which caused a carb to flood. This doesn't sound like your problem, but if you're pulling them out for cleaning and inspection they may not survive re-insertion… it's best to replace. There are complete pattern kits of everything rubber (and the needle valve) for the float bowls available at about £18 per carb (don't bother to look at genuine Yamaha prices), but as the little O-rings are probably all you'll need you can get a universal assortment box (http://www.ebay.co.uk/itm/201329092450) for about £5.
Taking them on and off is a bit of a faff so if you've an extra length of petrol hose and a separate petrol reservoir, it's worth checking that the fuel levels are correct while the carbs are on the workbench.
Post by: 110% on 19 April 2015, 10:00:46 am
The fuel tap is open - it is something I always forget to turn it back on after I take the tank off! I'm going to have a look at the fuel filter first following the comments from Fazerrider Darsi and Anutz.
I'll keep you posted!!!
Post by: 110% on 19 April 2015, 11:49:07 am
When I took the carbs off though there was some quite salty deposits around the insides of the carb rubbers.
<img src="http://foc-u.co.uk/MGalleryItem.php?id=2534" alt="" />
Post by: darrsi on 19 April 2015, 12:05:02 pm
I've now bypassed the fuel filter and fired it up with the same problems. It's quite dirty so I'm going to replace it anyway but it isn't the cause of the problem. The fuel pump also appears to be working fine.
When I took the carbs off though there was some quite salty deposits around the insides of the carb rubbers.
<img src="[url]http://foc-u.co.uk/MGalleryItem.php?id=2534[/url] ([url]http://foc-u.co.uk/MGalleryItem.php?id=2534[/url])" alt="" />
I'd imagine over the years the airbox has breathed in moisture from either wet salty roads in winter, and could have even been owned by someone living by the sea before.
Nothing to worry about anyway.
Post by: 110% on 19 April 2015, 12:24:58 pm
Top tip: When removing the carbs, it makes it much easier to release the 2 throttle cables at the handlebar end to give yourself even more slack in the cables at the carb end to remove them from the bracket.
Post by: unfazed on 19 April 2015, 01:41:05 pm
I've now bypassed the fuel filter and fired it up with the same problems. It's quite dirty so I'm going to replace it anyway but it isn't the cause of the problem. The fuel pump also appears to be working fine.
When I took the carbs off though there was some quite salty deposits around the insides of the carb rubbers.
<img src="[url]http://foc-u.co.uk/MGalleryItem.php?id=2534[/url] ([url]http://foc-u.co.uk/MGalleryItem.php?id=2534[/url])" alt="" />
That is normal enough on a bike in the condition yours appears to be in the picture, clean them out with a vacuum cleaner and wipe them with WD40 which will make putting the carbs back on easier. Wipe the carb inlets the same way. To help putting them back on push back the airbox housing back as far as you can and tighten the 2 bolts. This stops the air box moving around when trying to refit the carbs
There is another inline filter where the petrol hose pipe fits on the centre carbs T piece. Be carefull removing it as the fitting between the carbs is plastic and you don't want to break it. See pic. This filter is usually forgotten, it just needs to be cleaned if it is dirty.
When cleaning the jets do not be tempted to poke steel wire through them, steel is harder then brass and can enlarge the jet, if crud needs to be dislodged use a bristle from a brass wire brush. I have found the cellulose thinners is good to clean the jets, but not for use on hands or rubber O rings. Remember to clean the emulsifier tubes also called the jet holders. On top of the emulsifier tube (jet holder) there is a seat which the needl goes through and is kept in position by the emulsifier tube( jet holder), it is a push fit, be careful it does not fall out with out you realising.
Post by: 110% on 19 April 2015, 02:05:27 pm
I think once these are all cleaned out it might work again!!
Post by: unfazed on 19 April 2015, 02:14:10 pm
Thanks for the reply unfazed. I think I've found my problem. There is a white goo in every float tray that's clogging the jets.
I think once these are all cleaned out it might work again!!
Taking the jets out to ensure they are clean will save taking the carbs off again.
Mosty likely a mixture of water and fuel, was the bike out in the weather or under a cover and idle for a while?
Post by: 110% on 19 April 2015, 02:17:26 pm
Carb 3/4 now. Ive got carb cleaner to clean all the jet etc and trying to do a decent job cleaning. I might have it sorted before sun down!
Post by: 110% on 20 April 2015, 09:31:39 pm
On turning the ignition the fuel filter obviously kicked in and took longer than usual to stop pumping and then all it took was a few cranks of the starter to get the fuel flowing through the system again, but once fired up it was roaring with the throttle open.
I've tried to attach some photos of the white gunk that had built up in the carbs. It was almost like the gelatin from a pork pie but not as tasty!
FZS600 clogged carb1 |
FZS600 clogged carb2 |
Post by: anutz on 20 April 2015, 09:43:23 pm
Need to do my carbs now...
Post by: anutz on 20 April 2015, 09:43:59 pm
Post by: 110% on 20 April 2015, 09:52:53 pm
The O-rings to the main jets I also left on as they were. They seemed like they were in good condition so again I didn't bother replacing them and soaked them carb cleaner with the jets.
If you're looking at taking your carbs apart soon, some of the screws were really tricky to remove without tearing the heads off, but a bit of WD40 left to soak and a knock with a hammer did the trick of loosening them.
Post by: 110% on 20 April 2015, 09:57:46 pm
Post by: Ebme Geek on 21 April 2015, 11:14:19 am
And if you have any water sloshing around the bottom of your tank you will get a little bit picked up every now and again and it's going to be a recurring problem :rolleyes
Check the drain tube is clear that drains the area under the filler cap.
and check the face that the rubber seal of the cap goes down onto is not rusty, mine was, cleaned it with scotch bright pad, treated it with loctite rust converter, let it dry and put a light smear of silicon grease on it - happy days ;)
Post by: 110% on 21 April 2015, 01:14:28 pm
Post by: darrsi on 21 April 2015, 01:25:49 pm
It's cheap on EBay.
I use it a few times every winter, it doesn't do any harm at all.
Saying that, if you were to have a lot of water in there it would need draining anyway and then the leak fixed.
Post by: 110% on 21 April 2015, 07:59:36 pm
It seemed fine revving it at the kerbside but then 1 min into a journey the engine randomly blips and begins to stall. If it leave it idling for a while it ticks over fine, until i get going again and whilst accelerating it runs like crap.
I think I'm going to have to completely drain the tank, and then the entire fuel system again to rule out any fuel contamination. The only other component in the air/fuel system that could be at fault is the fuel pump, but other than that I might be looking at an electrical fault from the coils??
Post by: darrsi on 21 April 2015, 08:44:13 pm
Post by: 110% on 21 April 2015, 08:58:24 pm
Post by: unfazed on 21 April 2015, 11:21:07 pm
I would suggest you remove the tank Drain the fuel out of it, than remove the fuel tap and clean the tap filter .
With the tap out drain every drop out of the tank. Refit the tap, put the tank back on but do not fit the front bolt yet.
Put about 1 gallon fuel into the tank and connect up the petrol pipe to the tap, remove the pipe from the outlet of the pump. Fit a long pipe onto the outlet and direct it into a container.
Turn on the fuel tap, turn the kill switch to run and turn on the ignition switch, the pump should pump the fuel into the container. This will do two things, prove the pump works and pump fresh fuel through the pump and filter. Refit the original petrol pipe to the pump, connect the fuel sender and lower the tank
Drain the carbs and with the the drain screws open run the pump to let fresh fuel flow through the pipes. tighten the drain screws and switch on the ignition. When the pump stops, turn the ignition off and on again, continue this until the pump stops pumping, this means the float bowls are full. Refit the tank bolt.
Now start the bike and try it.
Let us know how you get on.
Post by: 110% on 22 April 2015, 10:40:20 pm
Post by: 110% on 26 April 2015, 02:59:04 pm
I completely drained the tank, filter and pump and then finally the float bowls; took the filler cap apart to get rid of the rust and tidy it up, filled it up with some fresh petrol and away it went. One hiccup within 30 seconds but afterwards was running cleanly for 10 miles.
Does anyone want to buy 12.5l of what I assume is water contaminated petrol??!@
Post by: unfazed on 26 April 2015, 07:02:31 pm
Post by: sblar on 28 August 2023, 11:19:39 am
I'm now back on the road.Thank you so much for this very old thread. I had the exact same problem, with the exact same solution :D
I completely drained the tank, filter and pump and then finally the float bowls; took the filler cap apart to get rid of the rust and tidy it up, filled it up with some fresh petrol and away it went. One hiccup within 30 seconds but afterwards was running cleanly for 10 miles.
Does anyone want to buy 12.5l of what I assume is water contaminated petrol??!@
After testing the pump and taking the carbs apart, I found this thread.
I simply drained the tank and fill a few litres of new petrol in it. There was quite a lot of hickups still, since I didn't drain the fuel pipe, filter or float chambers, but it finally swallowed all the bad petrol and got back to normal operation.
Learning: Don't leave the bike in heavy rain for a long period with only a few litres in the tank :lol
Post by: Gnasher on 07 September 2023, 01:07:54 pm
Learning: Don't leave the bike in heavy rain for a long period with only a few litres in the tank :lol
Better still replace the filler cap seal ;)
Post by: sblar on 24 September 2023, 09:25:14 am
Post by: Gnasher on 24 September 2023, 03:16:17 pm
Rigth, except that the seal isn't sold separately and the complete filler cap is around $350 :'(
Try these
https://mtp-racing.com/Fuel-Tank-Cap-7-Holes-MTP6626__Yamaha-FZS-600-N-Fazer-RJ021-022-1998-2001_1 (https://mtp-racing.com/Fuel-Tank-Cap-7-Holes-MTP6626__Yamaha-FZS-600-N-Fazer-RJ021-022-1998-2001_1)
or
https://www.wemoto.com/bikes/yamaha/fzs_600_fazer_sp/01/picture/fuel_cap_with_spare_key (https://www.wemoto.com/bikes/yamaha/fzs_600_fazer_sp/01/picture/fuel_cap_with_spare_key)
You could also try these, you need to measure the rubber and email them. Like many parts they aren't always model specific in that they use off the shelf stuff and fit the same parts across many models to cut cost.
https://www.ncjetski.co.uk/products/yamahagenuinefuelcapseal-yamahamarine-yagp7u78320100 (https://www.ncjetski.co.uk/products/yamahagenuinefuelcapseal-yamahamarine-yagp7u78320100)
or use a universal and cut it to size, you just need to make sure it's big enough and the same thickness.
https://www.ebay.co.uk/itm/402352153009?_trkparms=amclksrc%3DITM%26aid%3D1110006%26algo%3DHOMESPLICE.SIM%26ao%3D1%26asc%3D20201210111314%26meid%3Dcbde3ce84a1a4a2ca0afd1e7bed05454%26pid%3D101195%26rk%3D2%26rkt%3D12%26sd%3D254523940092%26itm%3D402352153009%26pmt%3D1%26noa%3D0%26pg%3D4429486%26algv%3DSimplAMLv11WebTrimmedV3MskuWithLambda85KnnRecallV1V2V4ItemNrtInQueryAndCassiniVisualRankerAndBertRecallWithVMEV3CPCAuto&_trksid=p4429486.c101195.m1851&amdata=cksum%3A402352153009cbde3ce84a1a4a2ca0afd1e7bed05454%7Cenc%3AAQAIAAABUObhgc4Nk8%252BdtAwOww4FKLaj%252FQ5qqgDlQCuqZA43WcPFUWDERCUugbbOk7XQv0JXlBfqCg2xKF3WcPghxGMFw2oSlXvfExEaMYr7I7LmrHcP6czY1wIMt0ORyKiCWt95xldincyyBx3g%252BNDW%252B%252FhWUgTaBhK6xAm%252BJIbCOMehu%252Bdwgrp%252FutCPvyb8KO9h4rrJ0zH9wH4QobXz71MGkE0ROQ1Hp%252FQIAyDYcoPyas31Fsuv%252FllmciFPrIzkYqBWNCaOlryzNJ6lf5z0%252Fm9kz5D7yymukXtC3i3DDxtPo74rqDWM1sOOWuJNnXvNL1cOWxu%252FfHQ7Nly2YFBr4k0CGFy5XUwSBBMOSVDsInvUk7n9PDPSGz0ZDz0k9TnESn%252FeaOdLHPSlfno9o6QmA%252BL47hQ0q4BoAb%252BZUBqKJYExpVSLPrJrvXn50CIVRiEvw4qgkxT%252BGw%253D%253D%7Campid%3APL_CLK%7Cclp%3A4429486 (https://www.ebay.co.uk/itm/402352153009?_trkparms=amclksrc%3DITM%26aid%3D1110006%26algo%3DHOMESPLICE.SIM%26ao%3D1%26asc%3D20201210111314%26meid%3Dcbde3ce84a1a4a2ca0afd1e7bed05454%26pid%3D101195%26rk%3D2%26rkt%3D12%26sd%3D254523940092%26itm%3D402352153009%26pmt%3D1%26noa%3D0%26pg%3D4429486%26algv%3DSimplAMLv11WebTrimmedV3MskuWithLambda85KnnRecallV1V2V4ItemNrtInQueryAndCassiniVisualRankerAndBertRecallWithVMEV3CPCAuto&_trksid=p4429486.c101195.m1851&amdata=cksum%3A402352153009cbde3ce84a1a4a2ca0afd1e7bed05454%7Cenc%3AAQAIAAABUObhgc4Nk8%252BdtAwOww4FKLaj%252FQ5qqgDlQCuqZA43WcPFUWDERCUugbbOk7XQv0JXlBfqCg2xKF3WcPghxGMFw2oSlXvfExEaMYr7I7LmrHcP6czY1wIMt0ORyKiCWt95xldincyyBx3g%252BNDW%252B%252FhWUgTaBhK6xAm%252BJIbCOMehu%252Bdwgrp%252FutCPvyb8KO9h4rrJ0zH9wH4QobXz71MGkE0ROQ1Hp%252FQIAyDYcoPyas31Fsuv%252FllmciFPrIzkYqBWNCaOlryzNJ6lf5z0%252Fm9kz5D7yymukXtC3i3DDxtPo74rqDWM1sOOWuJNnXvNL1cOWxu%252FfHQ7Nly2YFBr4k0CGFy5XUwSBBMOSVDsInvUk7n9PDPSGz0ZDz0k9TnESn%252FeaOdLHPSlfno9o6QmA%252BL47hQ0q4BoAb%252BZUBqKJYExpVSLPrJrvXn50CIVRiEvw4qgkxT%252BGw%253D%253D%7Campid%3APL_CLK%7Cclp%3A4429486)
It's also possible it's not the rubber but the tank neck that's the issue, either repair it, if possible or replace the tank, for an undamaged one.
Post by: sblar on 24 September 2023, 06:21:16 pm