87 vmax 540


I will make a note and check my VK books at home and check back next week.. Generally , it will need to not interfere with ability to get wide open throttle and cable
shouldn't dangle at idle.....
My older engine direct injected into the manifolds and my newer one into the fuel stream before the fuel pump ...
Reasons told ,, when you slowed down from high rpm with direct , the rpm would fill the crank with extra oil and sputter when reapplying the throttle..
Newer stream version worried me that wide open put lots into fuel line just in time to be rich when you back down,... if you idled for a while and used that up
and then had a WOT run , ALL the lean mix is going in ????
BUT mine had been killed by someone previous using an ether can to start it and unannounced to me and I didn't pick up on it until the piston had
flaked into the ports and pin 3/6" through the wall .... Never batted an eye on performance ,,, just wouldn't idle.
Ron

is yours direct or stream
 
Been a long time since I've done one and would have to dig out my service manual to be sure but this is as I remember.

Things for sure- adjustment is done midway on the cable. There is a spot there where the outer sheath is split with and adjuster in it. You have to pull back the outer rubber that keeps water out to see it.

First as with all Yamaha injection the carbs must be adjusted first. Idle and airs screws set. Cable and throttle pull set so idle and WOT will happen. Once that's set and oil pump cable adjuster is exposed hold the thumb lever in the wide open position and adjust the cable so there is a little freeplay in the middle at the adjuster. If you look at the cable end that slides into the adjuster it has a little dot or round dent in it. That is the freeplay mark. Pushed into the adjuster you shouldn't see it. Pulled out until you feel resistance you should. It's not much. About .010.

This gives the pump full stroke at WOT without binding throttle action at all.

The 540 Vmax injects oil into the fuel lines just upstream of the fuel pumps. This is the BEST system out there. Yamaha started doing it with the 540 and has done it with all their higher end sleds ever since. This system allows the fuel pumps to mix the oil so it is even properly dispersed through the engine.

The lean/rich thing Hydraulic Ron is talking about is a myth. Completely untrue but has been getting regurgitated for years because people don't understand how oil injection works. Many people think the system is varying flow to change ratio and if true would create these mythical lean/rich mixtures. Truth is the oil system varies rate because it must do so to keep a consistent even ratio. The carburetor is a varying rate fuel delivery system that changes how much gas is given to the engine depending on RPM and load. The oild system must be able to match that ability to stay even. That's why it changes delivery rate.

opsled
 
Ready rider .... I copied the pages including if you had stripped it apart and the shaft height settings .. PM me your email if needed ..
..
Opsled ,,, thanks as that is the first time someone has worded how it works in such a way it made sense to me and the difference on the newer engines ...
So in my mind if the sled was working at 50;1 ... the upstream method will always pump the correct amt to try and hold that ratio in the fuel line .. makes sense.
....
I need to have a look at my engine as the orig came with the fuel line injection and the engine I found to replace it was older , diff reed size and older design,, SR540 possibly ?
..
My fluid drives are all old style and most of the miles were put on a 74 TL433(bought new) ... almost all bush trail... The eng / converter slips until about 35mph and around 3600rpm
and it was a miser on oil about a quart of oil to 20 gallon (imp) of fuel used.... and ran well and pretty clean... The 643 versions either came to me seized or
with the oil injection unhooked and being mixed . Any of the 433 I took apart that were seized generally looked like they seized sitting with no scoring.
.
Thanks for the schooling
Ron
 


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