Thumper Club Forum
Technical => Bike Problems/Questions => Topic started by: Danxup on August 30, 2019, 02:54:35 PM
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Fuel in the crank case .. been stood probably 4 weeks with fuel in tank and tap on prime.. running all standard stuff . Any ideas? Its also leaking out of the oil seal on gear linkage i assumed thats just because the petrol has thinned the oil.. help me....arrrgh
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I'm not an srx specialist or anything, but the easy route for petrol into the engine is straight down the intake. Or even from the carb into the airbox then from the airbox into the engine via breather tubes. In both cases the problem is the float valve passing.
Whatever you do make sure you drain it all and renew the whole quantity oil i'd say.
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Ditto, no SRX specialist either, but it's a common failing of Japanese bikes of the era to not have a carb overflow, so if the float valve is sticking, the fuel will find its way into the crankcase either straight through the carb intake or through breathers as Andrew says.
My F650 did this a couple of times till I rebuilt the carbs, infact it leaked enough fuel into the crankcase to cause a hydraulic lock!
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Cheers . .. im bloody stuck for time more than owt .. thanks for replys
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well well, i've had this happen to me on my SRX6 a while ago.....
first thing is to strip the fuel tap and get a service kit for it, not expensive...
second.... shouldn't leave in 'prime' ... this allows fuel into the carbs all the time (the whole idea of 'prime', should be set to 'on' or 'res' ... which are opened by vacuum once the engine is running ... so 'in theory' .. with the engine stationary the fuel will be 'off', this assumes the tap is sealing properly ... hence the service kit.
3rd.... 'in theory' the float/needle valve assembly should have stopped excess fuel overflowing into the crankcase , so this will need addressing as well.
4th ... drain drain drain and drain again ....(oil tank, oil filter, crankcase, oil cooler (if you have one) ) ,anything to get rid of ALL the contaminated oil ....
5th ... refill with oil ... start make sure (with the bleed hole open) you have good oil flow..... let it tick over until it is hot. ... check everything works ok then a very gentle run, back home.... complete #4 again, then #5 .... this is important .... 'cos you're never going to get all the fuel/oil out and your 1st fill will certainly have contamination ... and a second oil change is a lot cheaper than a seize up.
drain IMMEDIATELY .... i left mine for a couple of weeks and the clutch plates swelled up and i had to strip it out wash everything and dry it all out.... believe me you don't want to be doing that!
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Sounds like pretty soul destroying stuff Steve, but sound advice all the same. The joys of classic ownership eh 😢😢
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Agree with everything SteveL has said and would emphasise the use of an additional fuel filter between the petrol feed from the tank to the fuel tap with the 'Prime', 'On' and 'Reserve' options before the carb. Also replace the float needle and check that the float needle seat and float are sound, so that they are unlikely to fail again.
Having been caught out at traffic lights, after cruising up the A9 at ~60mph, outside Newtonmore at some roadworks. Shut the throttle, cruised to a halt and promptly disappeared in a cloud of petrol vapour, as petrol spewed from the carb all over the underslung BSM exhaust; the float needle being held open by a minute particle of rust. :o Turned the ignition off and this stopped the vacuum and shut the petrol tap. Fortunately, I didn't fill the sump etc and the machine didn't ignite!
I have recently started using Westway Lubricants motorcycle oil (10w40 semi-synthetic for the SRX's and Honda Bros) and so far have not had any problems; the prices are very reasonable, especially if you buy the 20 litre drum. ;)
Link to Westway Lubricants eBay shop: Westway_Lubricants_eBay_shop (http://www.ebaystores.co.uk/Westway-Lubricants-Shop/_i.html?_nkw=10w40+semi-synthetic+motorcycle)
Link to Yambits for SRX600 1986-1991 float needle/seat kit: Yambits_srx600-carb-float-valve (https://yambits.co.uk/srx600-carb-float-valve-p-45141.html)
You may prefer to use Fowlers of Bristol for the genuine parts and their website and service are very good.
Link: Fowlers_SRX600_fuel_tank_includes_taps_parts_list (https://www.fowlersparts.co.uk/parts/4048725/srx600-1xl-1987-999-a/fuel-tank)
Link to the carburettor parts list as well: Fowlers_SRX600_carburettor_parts_list (https://www.fowlersparts.co.uk/parts/4048709/srx600-1xl-1987-999-a/carburetor)
Hope this helps you to get the old baggage up and running again. If there is anything that you don't understand, ask!
My regards, Bill
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Cheers chaps.. mum watched the baby long enough for me to remove the tank lastnight. To be fair i think most of the fuel that was in it is now in the crank case and on the garage floor . Also the fuel tap was on run not prime .. should i still over haul the tap? Or does this suggest the problem lies with the carb? Thankyou so much for all the sound advice.. knowing my luck the clutch plates will be swollen and all the lot .. bloody hell
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Also i did fit small inline filters between tank and tap some timee ago on bills advice. Gonna drain out the crank case and oil tank this morning but wont have time to start digging properly until sunday morning. Its all abit upsetting. 🤢
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You definitely need to look at the float valve. See if it's a particle in the way or wear on the taper or seat. If it's not an actual particle causing the problem there's a possibility the bike will run fine, even if the valve is slightly worn. Sometimes it's just that the amount that passes is so slight it doesn't affect the running, but will flood the float chamber if left with a constant head of fuel above it.
I suspect your fuel tap is dodgy as well, if I've understood you right. If there's an "off" position then I'd use it every time you park up.
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I'd rig up a test for the tap. I'd disconnect the hose to the carb and attach a longer one down to the floor into a jam jar or whatever. I'd try the tap in all its positions and see what happens in each position over a period of time. Just a thought. It's what I'd try if I suspected the tap.
Tbh I hate diaphragm taps and if I was keeping the bike I'd see if I could convert to a basic manual on/off/res tap (checking the flow rate) but that's just my own feeling.
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Thankyou. Yeah the diaphragm tap seems like abit of over engineering on yamahas part.. however i like the bike to be as original as possible so i think ill just bite the bullit and overhaul it.. Hopefully get the carbs off tomorrow and have a butchers.. 🤔
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All sounds like good sound advice to me Dan. The best of luck with it and keep us posted 🤞
Cheers..Michael
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Morning Dan,
If fuel tap was in 'Run' position, it would suggest that there is a fault in the fuel tap, as the diaphragm should remain closed; due to their being no engine vacuum to open it.
This does not mean that there is not a particle/foreign body/wear allowing fuel to flow into the carb and then into the engine; so the float bowl needs to be dropped and the float needle, it' seat and the pivot pin all need to be inspected for wear/obstructions. Having got this far into the guts of the carbs, I would renew the float needle, it' seat, as a matter of course, even if the wear appears minimal. You don't want your wedding tackle to be flambe'! :o :o :o
You will also note that the carburettor mountings onto the cylinder head and rubber moulded hoses leading back to the airbox can make the removal and replacement of the carbs a vexing operation! ::) Check for splits in the mounts to the cylinder head. If all appears sound I would recommend soaking all four inlet tract rubber mouldings in 'ArmorAll' in a plastic tub (no need to immerse, just give them a good coating), then a good massage. This will remove a load of dirt, if present and make the mouldings more pliable. Give the mouldings a wipe down and then use just a wee touch of 'ArmorAll' to act as a lubricant when reassembling.
I have persevered with the vacuum taps on both Sally (twin shock 600) and The Mono (SRX400 monoshock with XT600E engine). I just use 'Prime' for initial startup and then switch over to 'Run' when running. Because the threads were stripped in Sally's fuel tap body, I used epoxy resin to hold 2 pieces of threaded rod as studs into the tap body and then used self-locking nuts on the outside to hold the tap to the frame bracket. Whilst other taps may fit, the whole design/position of the tap makes it difficult to attach an alternative, neatly, so far as I am concerned.
Steady away and good health, Bill
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wot Bill said!
I'd also fit new hoses, nice new flexible ones, unlike the rock hard bu55ers you'll be removing, make reassembly so much easier (and fuel tight)
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original post says that the fuel tap was on prime. so i wouldnt rebuild the tap just yet, sounds like it wasnt at fault, cos it was on prime, not on or reserve..
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Aye johnr,
Cheers chaps.. mum watched the baby long enough for me to remove the tank lastnight. To be fair i think most of the fuel that was in it is now in the crank case and on the garage floor . Also the fuel tap was on run not prime .. should i still over haul the tap? Or does this suggest the problem lies with the carb? Thankyou so much for all the sound advice.. knowing my luck the clutch plates will be swollen and all the lot .. bloody hell
Hence the movable feast of potential jobs required! ;)
Hope you are in good fettle?
My regards, Bill
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So... drained the oil/ fuel out of the crank case snd oil tank .. had the bike on its side to make sure its all out.. checked air box which is dry thankfully.. removed fuel tap and carbs no filth in the float bowl carbs seem fine its not long since i had the tank repaired and lined and carbs cleand twice .. and replaced all pipes.. also bill did the armour all trick om your recommendation when sorting out the tank and carbs last time. Thanks by the way its good gear that..however i think while ther off ill replace needle and seat etc anyway. Havnt had time to dismantle the tap yet but i think ill just overhaul it anyway.. just realised in my haste i forgot to take out the oil filter.. probably be one night this week befor i get in the garage again now. In the mean time ill be ordering parts.. also the clutch has gone slack so im assuming ill have to replace the plates? Cheers evryone
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if your clutch was in good nick before the fuel problem, then i'd strip it, clean it thoroughly x 2, let it dry out completely, then reassemble, that worked for me.
if you're ordering a service kit for the fuel tap, .... i got mine from M&P, and although i've always been happy with their stuff, it took 3 attempts to get the right kit.
the pic on their website looks like the right one, but bears no resemblance to whats in their stores.... speak to a human, they rang up their supplier while i was on the phone and identified the right part. and i did get credit for the wrong ones, just a pain in the arse and a waste of 2 weeks. of course, i don't have the correct part number ... bunged the packet away.... what a plonker!
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Just a tip, I'd try the carbs off the bike after you've fitted new float valves and seats. Sadly, in my experience at least, the quality of carb rebuild kits is very hit and miss, and in the past it's taken me several goes to find a combination of valve and seat from several different kits before getting the valve to stop leaking.
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Bloody hell its a minefield out ther.. ill let you know how i get on.. if i didnt love how this bike rides id probably give up
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Stick wi it Dan! ;) Today the Mono was given a canter and there is nothing like a single getting into it's stride! ;D A lot of elbow grease, dosh and "Am I doing the right thing?", but very addictive! :o
My regards, Bill
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Hell yes I will defo echo Bills words there, stick with it Dan. I've been on with my "tracker project " for approximately 5 years🤣🤣... granted my accident did get in the a touch but as Bill says can't beat a decent single. Best of luck 👍.... cheers. Michael
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I will i still have the 400 on the road anyway.. im going to order the parts and oil and filters on Wednesday when i get paid. Ill let you know how i get on.. hopefully get time to get in the garage inbetween looking after baby working and life in genral.. may even take an afternoon off work once all the parts and oil arrive
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yeah, it's difficult making time for the bike(s) when you're in full time work and a family to attend to, sometimes us old buggers semi or fully retired with family all grown up and fled the nest, don't appreciate (or remember ) the difficulties.... I sold my velocette viper in 1976 when i left the raf, and didn't get another bike until 1994 when i got my #1 srx6. so i have a lot of admiration for you guys who keep your bikes and fettle away through thick and thin.
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Steve just a quick question... what did you clean your clutch plates with and how long did you leave them to dry out.. havnt got the buggers out yet but hoping to get the clutch cover off after work today. Just orderd the gasket and oil and filters.. ill be ordering rest of bits on my dinner break. Cheers
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All bits orderd. Got fuel tap kit from yambits along with float needle and seat. Hopefully get in garage sunday morning and have a go at it
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Aye Dan,
Steve may use something else, but I use Brake and Clutch Cleaner. Clean everything down with it (inside of case, metal and fibre plates, scrub with a stiff brush/tooth brush and leave to evaporate) having removed external case muck with paraffin and or AutoGlym Cleaner, before splitting the cases.
I purchase my Brake and Clutch Cleaner from my local motor factor, about £8-50 for a 5litre can.
Just be careful how you dispose of the manky stuff and do not have a fag over the top of it! :o I apologies if this is all obvious information. :-X
My regards, Bill
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Bill beat me to it.... yes, brake/clutch cleaner .... or a good proprietary degreaser ... let 'em dry as long as possible
good luck
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Cheers fellas... still havnt had chance to get in the garage. Hope the clutch plates arnt buggerd by now .. the parts are all here and the oil and filters so just got to find time now and get some break cleaner. Carbs are off and in bits fuel tap off just need to get bloody time.. ill be sure to let you know soon as ive made any progress .. thank you all so much for your input..
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Aye Dan,
WARNING!!!!!
Be careful with your rubber 'O' rings etc. in the carbs, they can be sensitive to carb or carb/brake cleaner and perish!!! :-[ :-[ :( :'( Newer 'rubber' parts are more likely to be resistant to this chemical reaction wi' the cleaner, because they are ethanol resistant; but I am cautious about this when immersing or agitating parts, with a brush, in the cleaner.
All the best, Bill
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Ey up lads.. just thought I'd give you an update.. new needle and seat in carbs . Fuel tap overhauled both ready to go back on bike. Couldn't get bloody nut off kickstart leaver today to get clutch cover off any advice? I thought id borrow my brothers impact wrench this week and try and shock it off. Or is it left hand thread.
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normal thread ..... try a bit of heat (not too much).....
i have heard of them coming off during a ride. .... with subsequent loss of a kick start lever, at about a squillion pounds a piece ... probably why it's on so tight
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Yeah when i restored the 400 the kickstart was cracked coulsnd find one for ages ended up getting one from japan for about 100 quid with postage etc.. then one came up on ebay for 30 quid a few weeks after so i snaped that up aswell so i now have a spare.. ill try abit of heat and the impact wrench tonight if i get time.. the clutch has actually cone back but i figured i might aswell have it out while im at it
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Managed to get a bit of garage time this aft got the carbs and fuel tap back on and clutch cover off anf clutch out and cleaned . Ill leave the clutch out to dry for a week or so then kett you know how i get on . Cheers for all the advice. Also one of the clutch springs is broken should i replace the lot or just the one ? 😣
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do the lot, not expensive .... just changing one is not recommended
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Right i will cheers steve. Ill get some orderd
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;) Bill
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Ey up chaps... got all the jobs done went for a steady run. Came back droped the oil replaced the filter and re filled with oil.. thought id take her for a run i got about a mile and the clutch went slack and gradually went completely.. it then dawnd on me that i mustn't of tightend up the lock nut on the clutch assembly.. i was right i droped the oil again took clutch cover off and sure enough the lock nut had come off..
Only problem now is i cant remember if ther was a washer or not . If ther was it must of found its way into the crank case..
Could it cause a total disaster? Im abit annoyed with myself to be honest..
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Aye Dan,
OH! B.....! Here is a link to the Fowlers parts lists for the clutch: SRX600_clutch_parts (https://www.fowlersparts.co.uk/parts/4048714/srx600-1xl-1987-999-a/drive-belt-and-variator)
The washer, from your description (Part number:YBS66-6), appears to have gone 'walkabout' :( I doubt if the washer will be sucked up into the oil pump, providing your strainer gauze was in good nick and unlikely to become tangled up in the gears, but slide about the bottom of the cases! :o You could try a little 'fishing', with a slim telescopic magnet, whilst the cover is off and see if you get lucky. :)
Steve may be of a different opinion about the washer floating about, but I'll leave it up to you whether you decide to leave it alone if you cannot 'fish' it out.
All the best.
My regards, Bill
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Purchased a telescopic magnet . Ill let you know how i get on. Cheers evryone
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To my knowledge (and failing memory), i don't think there was a washer on the adjusting thread .. leat, not on #1 when i put it back together a month ago .... but hey!... maybe i lost mine too :-)
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Now then.. i finally got in the garage yesterday and got the 600 back together. I fished and i fished but didnt find a washer so decided to convince myself it didnt have one on.. ive re filled with oil and run her up . Had a little ride up and down the yard and evrything seems ok . Didnt take her for a proper run as its out of tax and ill be sorning her till spring.. also the fuel seems to be staying were it should be so it looks like the new needle and seat and overhauling the tap has done the trick. Thankyou so much for all your input fellas.. ive no doubt ill be picking your brains again in the future.. next job is to drain the fuel from the 400 and the 600 for winter.. hopefully ill get in the garage again soon. For now its work and dad duties.. cheers!
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A pleasure Dan. :)
Enjoy the "Dad duties" as well, even though they can be taxing, they will use their wings in the blink of an eye; but still ask for "Dad advice many years on. ;)
Good health, Bill