I baught a 1998 VMAX 600 from a guy who listed it here and EBAY, as the story goes he baught it from a guy with 1900 miles on it. Took it up north where is step son blew it up because it had am pistons, so he had it honed and put new oem pistons and rings in it also a new oil pump just to be safe! He also turned the oil pump up to full rich.
Well I babied it for 200 miles, stopped every 30 min and let it cool, varried the rpms never going over 6000, at about half of the third tank of gas I opened it up on a road........ You know what happened next!!!
It lost power, I limped it to the next trail head at high rev it would smooth out but idle was Very rough. Knew the motor was junk!!!
When I contacted the seller he told me to turn the idle up till it ran "smooth enough" and take it to white star auction!!!!!!!!!
So I pulled the motor and found the pistons to be 10-15 thousands too small!!! Almost no oil used with and 3 tanks of gas burned I'm wondering why???
I am also wondering how much I can bore the cylinders???
Upon pulling it appart I found under sized pistons slopping around in the sleaves!!!! Like 10-15 thousands to small!!!!!
Well I babied it for 200 miles, stopped every 30 min and let it cool, varried the rpms never going over 6000, at about half of the third tank of gas I opened it up on a road........ You know what happened next!!!
It lost power, I limped it to the next trail head at high rev it would smooth out but idle was Very rough. Knew the motor was junk!!!
When I contacted the seller he told me to turn the idle up till it ran "smooth enough" and take it to white star auction!!!!!!!!!
So I pulled the motor and found the pistons to be 10-15 thousands too small!!! Almost no oil used with and 3 tanks of gas burned I'm wondering why???
I am also wondering how much I can bore the cylinders???
Upon pulling it appart I found under sized pistons slopping around in the sleaves!!!! Like 10-15 thousands to small!!!!!
daman
New member
Who was this yo-yo expert engine builder???? he needs a GOOD 
wtf...
anyway you need to know is it the stock plating bore? or did he have it bored and sleeved? post some pics up so we know what direction this things needs to go..
sorry you were screwed over...
wtf...anyway you need to know is it the stock plating bore? or did he have it bored and sleeved? post some pics up so we know what direction this things needs to go..
sorry you were screwed over...
I think what happened is, he tore it down to build it and found the stock bore to be over tolerance.... Instead of boreing it he honed and piston slapped it to save the money! He already had it listed when he popped it... I just can't figure out why it wasn't drawing any oil..... Could it be lack of vac pressure from the blow by????
How much cani bore the stock sleeve???
How much cani bore the stock sleeve???
daman
New member
If the cyl is junk find a good used stock one,dont sleeve it, the oil pump needs inspection to see whats the deal,was the cable hooked up and moving the pump arm?
Yeah the cable seemed to be tight and working right... The pump looks new.... But as loose as the pistons were I'm just wondering if the motor was building any vac pressure.
Is the large black hose going to the block a vac line for the oil pump???
Is the large black hose going to the block a vac line for the oil pump???
daman
New member
thats the pulser line from the crank case runs the fuel pump, we need pics,he could have put a 500cc oil pump on also they flow less cc's of oil vs the 600.thstorms said:
is the pump adjusted right??
I burned 3 tanks of gas and the oil only went down maybe a 1/4"!!!! do 500s use that much less oil???
daman
New member
not sure exact cc's..
is pump adjusted right, with throttle wide open do marks line up?
is pump adjusted right, with throttle wide open do marks line up?
Was the oil pump bleed or was there an air lock in the line?
Daman what is the difference between the 500cc and 600cc oil pump and can the 500cc be adjusted to work on a 600 cc engine
daman
New member
all i know for sure is the 500cc pump pumps less oil at operating rpms then a 600 does,i reserched this few years ago when i though i needed a new pump.mtnmaxman600 said:
i wouldnt advise it no..
horkn
New member
mtnmaxman600 said:
I can tell you the part number is different from the 500 to the 600, but other than that I don't know. You would assume that the 500cc oil pump would put a little less oil out.
daman
New member
it does....
it was past the mark at wot, the arm was almost past the extrusion at wot.....
daman
New member
if thats the case she should have been flooding with oil not starving,the pump may be bad? was it a new new pump??
it would still do 70mph..... it bleeds blue!!!
these are the only 2 I took other than shots of how awesome it looks with a set of modded precision skis on it....
the marks in the other piston are from trying to get the wrist pin out of a mangled piston...
BornYamaha
Member
Once it's repaired, and oil pump fixed/replaced, through some premix in it until your sure it's drinking the oil at the correct rate. Better safe than sorry.
Good call!!! Im never the guy to come up with the easy solution....
It sure is fun mixing gas, no long trips....
Ok so problem solved, rebuild it, take pics, mix gas and figure out oil issue...
Now the other question....
How much can I bore the cylinders????
It sure is fun mixing gas, no long trips....
Ok so problem solved, rebuild it, take pics, mix gas and figure out oil issue...
Now the other question....
How much can I bore the cylinders????