Thumper Club Forum
Technical => Bike Problems/Questions => Topic started by: athula wilson on April 07, 2008, 07:31:39 AM
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Hi all,
Got the bike running after a top end overhaul, for which I had drained all of the oil and the bike is now fitted with a Monoshock tank to the front of the engine.
And there seems to be a problem with the oil distribution pump. I filled up the oil tank and ran the bike for may be 20 seconds or so an thought I see if there is any oil circulation by removing the vacuum release screw at the to of the oil filter cover and no oil was coming and when I opened the oil filter and ran the engine there was still no oil coming. Tried this 3 or four times every time the engine must have run for about 30seconds or so maximum with out any oil coming through.
So I remove the valve access cover and poured oil from the oil tank in to the engine and as the engine was running the oil did return to the oil tank which means the scavenger pump is working.
Then I took off the oil supply hose from the tank to the engine and there was no blockage in the hose.
Then I blow in to the hole, which the oil supply hose connects to (using a piece of hose) and no air was passing. I suppose this does not mean there is a blockage but just normal pump characteristic (?). As I cannot see a reason for a blockage.
Next I removed the right hand engine cover to take a look at the distribution pump, I have the feeling that this may be behind the clutch housing (need to get myself a manual!)
Just to summarize.
No blockage in oil supply to the engine
Scavenger pump is working
No oils from the oil tank is getting circulated
Just wondering
Do I need to run the engine for longer than 30 or 60 seconds in one-go to things to start moving?
Could it be an air trap in the distribution pump?
In case I need to access the distribution pump,
Do I need to remove the clutch housing?
I need a right hand engine cover gasket, suppose applying silicone gasket is going to be bit of unwanted hassle in the long run or would you recommend it? I have seen whole set of gaskets for £40,
sorry about the long list of questions but would be very grateful to your advice/ recommendations.
Many thanks, Athula
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The feed from the oil tank to the oil pump may need bleeding. In the past I have done the following
- Disconnect the return pipe into the tank and block the outlet.
- Make sure there is at least 1 litre of oil in the tank
- Attach an airline to the breather on the oil tank.
- Using a compressor apply pressure to the oil tank, this doesnt have to be high, around 10psi will be fine.
- Kick the engine over untill oil comes out of the oil filter.
This process helps 'bleed' the pump. I'd try this before stripping the pump out.
Steve
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It sounds like you've run the engine long enough 'dry' if there is no oil circulating then any more dry running could start to damage components.
Certainly pouring oil into the rocker cover cavity is a good idea, anything up to a litre, and allow an hour or so for it to settle in the base of the engine.
If you have access to starter rollers this is a better way of bleeding the oil through, remove plug, put bike in 2nd gear then spin up on the rollers with the bleed screw removed form the top of the oil filter, you should see a spout of oil fairly quickly.
If you don't and bearing in mind you have changed from the standard oil tank to the front mounted monshock tank......review all your fittings and pipe runs....
If my memory serves me correctly....the standard oil tank does at least offer some degree of gravity feed...the front mounted one doesn't as it is lower.
and then there is the question of.....why change from the lovely purpose built twinshock oil tank to what I can only describe as the rather ugly mono shock version which spoils the lines of the bike I think....did you have a problem with the old one? and presumably you had to use the mono exhaust down pipes too?
SteveL
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The feed from the oil tank to the oil pump may need bleeding. In the past I have done the following
- Disconnect the return pipe into the tank and block the outlet.
- Make sure there is at least 1 litre of oil in the tank
- Attach an airline to the breather on the oil tank.
- Using a compressor apply pressure to the oil tank, this doesnt have to be high, around 10psi will be fine.
- Kick the engine over untill oil comes out of the oil filter.
This process helps 'bleed' the pump. I'd try this before stripping the pump out.
Steve H,
Thanks for the comment.
As I had mentioned previously, I had tried blowing into the oil inlet at the bottom base of the engine but felt blocked.
But I will try you suggestion by apply compressed air
Thanks
Steve L,
It sounds like you've run the engine long enough 'dry' if there is no oil circulating then any more dry running could start to damage components.
Certainly pouring oil into the rocker cover cavity is a good idea, anything up to a litre, and allow an hour or so for it to settle in the base of the engine.
When I opened the side cover tings looked well oiled
If you have access to starter rollers this is a better way of bleeding the oil through, remove plug, put bike in 2nd gear then spin up on the rollers with the bleed screw removed form the top of the oil filter, you should see a spout of oil fairly quickly.
No access to rollers
If you don't and bearing in mind you have changed from the standard oil tank to the front mounted monshock tank......review all your fittings and pipe runs....
There is a free flow in to and out of the tank
If my memory serves me correctly....the standard oil tank does at least offer some degree of gravity feed...the front mounted one doesn't as it is lower.
But the system presumably works fine this the single shock (same)engine?
and then there is the question of.....why change from the lovely purpose built twinshock oil tank to what I can only describe as the rather ugly mono shock version which spoils the lines of the bike I think....did you have a problem with the old one? and presumably you had to use the mono exhaust down pipes too?
Thought you would ask, but I have fitted a XT exhaust pipe with a can under the single seat that eliminates the space for a usual position of the twin shock oil tank. Unfortunately I cannot attach images to this reply.
Please let me know of ant other toughts
Many thanks, athula
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I've seen the piccies! :)
And it looks loverleee!!
Just you wait and see boys!
a
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I've disconected,in the past, the feed from the oil tank to the engine, beneath the front sprocket, and using a 10ml syringe (one without a leur lock) filled with oil, have forced oil through the engine. Sometimes it takes a bit of pressure but it works for me. I wonder if it is the valve stoping the oil flowing out of the oil tank into the engine sticking. You more enlightened mechanics may have the answer.
Unfortunately you may need a contact to get you a syringe.
beeman.
ps let me know if you want one.
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Unfortunately you may need a contact to get you a syringe.
beeman.
ps let me know if you want one.
Yeah MAaaan ! I wanna Syringey Thingy !
Jethro
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Hi
When you say there is 'free flow into and out of the tank' do you mean you san see oil flowing with the engine running? or just that the pipes are clear?
If the former, then the only thing i can think of is the check valve at the bottom of the right hand engine cover....it is a spring loaded ball pressed against an 'o' ring....it is there to prevent oil migrating into the sump when the engine is stationary...it might be worth checking this (new 'o' ring seals are available from yamaha.
Is there an oil cooler fitted?
are all the oil pipes definitely routed correctly?
has the oil pump been removed for any reason?
steveL
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I've disconected,in the past, the feed from the oil tank to the engine, beneath the front sprocket, and using a 10ml syringe (one without a leur lock) filled with oil, have forced oil through the engine. Sometimes it takes a bit of pressure but it works for me. I wonder if it is the valve stoping (Is this the same valve that Steve L is talking about?)the oil flowing out of the oil tank into the engine sticking. You more enlightened mechanics may have the answer.
Unfortunately you may need a contact to get you a syringe.
beeman.
ps let me know if you want one.
Thanks, let me see if I have one myself
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Hi
When you say there is 'free flow into and out of the tank' do you mean you san see oil flowing with the engine running? or just that the pipes are clear?
The pipes are clear
If the former, then the only thing i can think of is the check valve at the bottom of the right hand engine cover....it is a spring loaded ball pressed against an 'o' ring....it is there to prevent oil migrating into the sump when the engine is stationary...it might be worth checking this (new 'o' ring seals are available from yamaha.
This may be it, Is this accessible with out having to remove the clutch housing
Is there an oil cooler fitted?
No
are all the oil pipes definitely routed correctly? Yes
has the oil pump been removed for any reason? Not by me, at least
Thanks athula
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Ok, well, I need to get a few things clear in my own mind I think.....
Presumably the bike has worked ok at some stage (oil wise)?
this being the case, exactly what has happened to the machine since it last worked ok?
Yes the check valve is reached by removing the right hand casing (clutch cover) after removing the kickstart and valve lifter mechanism. But, this check valve is very much a 'fit and forget' item, if it fails it would normally fail safe...i.e. stuck open, and in fact, i'm pretty sure when these engines are tuned for racing the valve is dispensed with (to allow unhindered oil flow) as 'wet sumping' isn't a problem on a race engine as they are usually drained after a meeting anyway.
so, at the moment i'm at a loss to think where the problem might be, personally I would back track, and fit the original oil tank and pipes and try to bleed the system using all the original kit, if that works then you at least know all the internal are working ok and you can look at the parts you propose to use in the future.
SteveL
Have a look at SteveH's website for some good info about oil feed etc find it in 'links' or go here http://www.srx600.net/
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Thanks for the comment.
As I had mentioned previously, I had tried blowing into the oil inlet at the bottom base of the engine but felt blocked.
But I will try you suggestion by apply compressed air
Thanks
I would expect it to feel blocked, you are blowing into the back of the pump. The pump is a 'lobe' type pump and if its sealing properly shouldnt let much air through. The reason for turning the engine over whilst apply pressure to the oil tank is to allow oil to pass through the oil pump. If the engine isnt turned over you are trying to force oil through the clearances in the pump, which if its in good condition will be small.
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Steve L & H
thanks for the latest feed back.
I'm at a lost as well. well one thing for sure is that it is not the oil tank or any problem in supply of oil from the tank to the engine. It seems that oil is not going pass the pump for some reason.
I will give it another go this weekend and will update you all.
thanks,
A
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Got the oil circulating not sure what the problem had been just blew some compressed air, which went un hindered and then filled up the tank and things started circulating.
But did managed something stupid, I had unscrewed all but one alan screw on the oil filter cover when applying compressed air and the cast aluminum cover basically broke at the point of the remaining screw (bugger!). Any chance of a spare filter cover?.
The bike seems to be over heating a quite a bit. Mainly because it seems to be running lean, It would not run at all with out the choke. I have changed the filter and the exhaust is fairly open and very loud. Is it worth trying SRX 6 main jets. I presume the SRX6/4 carbs are the same.
Thanks,
Athula
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A) yes, got a spare filter cover, make me an offer :-)
B) good news the oil is ok now, guess SteveH was right, an airlock seemed the most likely cause
C) not sure if the 400 cab bores are the same as the 600, certainly the all the jetting will be different, might be worth casting round for a set of 600 carbs, must be some about judging by the number of people fitting twin SU's and the like.
SteveL
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A) yes, got a spare filter cover, make me an offer :-)
Steve L,
It is your call, thanks, Athula