3aj start up after re bore
 

hello, i got my xt engine rebored and put back together by my mate some
time ago.i have turned it over using jump leads for extra revs but
cannot get oil to reach filter bleed screw. should i just go ahead and fire it up and expect oil to go where it needs to without any problems.
philly.
thanks in advance

image is 2007 2012 image soon.

open it.
 

I would open the oil filter cover and see if any oil is in there at all!

Do the usual prep of plenty of rags to catch any oil. If there's no evidence of any oil then I'd think of a) blockage somewhere or b) pump failure. (Is the filter in the right way?)

If there is oil in the filter, then yeah, I'd fire it up but only a couple of seconds then switch off. If still no oil coming from the bleed screw then see above a) or b). Maybe try and turn it over with no filter in..!?!? only for a few seconds!

it's funny as whenever a 'mate' has done a job he's generally messed it up.. I stay away from those mates! LOL!!

open it
 

i forgot to say i have spark plug out but is grounded for easier swing.not
that it makes any diff. as far as my mates competence its a 100% as he
has built alot of motors to date. thanks for concern and advice Geoffshing.

First of make sure your bike is sitting level (not on side stand) and one thing i did with my 3AJ after an engine rebuild was to open the left hand inspection cover & pour oil in there to prime the pump.

I was having similar problems as yourself, so i just tried that method & it worked for me. Ive heard other guys just fire it up & hope for the best, id rather know there oil in the system.

Once i had done that i fired up the bike & unscrewed the rocker inspection cover to make sure it was lubing the camshaft, it pissed out everywhere but at least i knew it was getting oil to the top.

Mezo.

3aj start up
 

thanks for that mezo but can you be a bit more specific,i have heard to take
out clutch then oil pump and pour oil in there to prime pump.that will cost me a gasket and two o rings and one more
thing those mono cross stickers are well nice,where to buy those.
thans in advance philly.

What i did was to open the inspection screw (the big one) with a slot in the middle of the left case, i found an old plastic bottle (brake fluid i think) which fitted in the hole a treat, i then cut the side out of the bottle to allow me to pour oil directly in.

Now im not saying this is a correct way of doing it? but i wasn't getting oil to the filter bleed screw before, but after i put some oil directly in out she squirted after turning it over (switched off).

Them stickers can be found here (page down to bottom) and pay attention to the sizes, they are all different.

Mezo.

3aj start up
 

too easy mate,i will kick her in the guts in the morning.

No need to take it out on the missus mate. :innocent:

Mezo.

Past the pump
 

Best is to make sure that the oil is passed the pump, in other words that the pump suction line only contains oil. Can be done by turning the oil pump by hand (this'll cost you a clutchcover gasket of course).
The first part of the line from tank to pump can be filled by slightly loosening the 2 bolts holding the oil line flange to the engine in place. When oil starts dripping out that part is filled.

Do not start the engine before oil has passed the pump!

Auke

Hi, a few years ago now, i rebuilt my 3aj and had exactly the same problem. what i did was find a plastic bottle lid that roughly fitted over the oil tank filler. i drilled a hole in the lid & using an airline turned way down to low pressure & placed over the hole. with the sparkplug out & bleed screw at filter out, turn the engine over with the starter. worked straight away. hope this helps

So you blew air in to the oil tank via the filler cap is this correct?
and that forced it round to the filter bleed screw right?

Mezo.

3aj start up
 

helllo to all who replied,
two days ago i put the oil in to generator
inspection cover and turned motor over about 500 cc oil.but still no
oil present at bleed screw.last night i took off gen casing altogether
and the oil has been sucked in to pump. today i put another 500 cc
of oil into gen inspection hole but still no oil at bleed screw.
i had already taken the pipe off the bottom of engine from oil tank to
make oil is flowing that way. i will try airline trick tomorrow.
thanks for advice all.

Yeah Mezo, the pressure forced the oil through, but you have to turn the airline well down & have a good seal at the filler. After a few seconds i had oil pumping out of the bleed screw no problem. Dr Auke helped me with some great advice during my first rebuild of a big thumper bier i have since sold the 3aj & moved on to an xt660x but still visit this great website regularly.

2 systems
 

Pouring oil in the engine will not help. The Xt engines have 2 oil circuits and effectively 2 oil pumps, although combined into one 'pump':
1. From oil tank to pump, then on to crankshaft, big end, piston, parts of the gearbox
2. Scavenging; returning oil to the tank while a sidestream lubricates gearbox. This circuit sucks from the crankcase.

At first startup it is most important to get circuit 1 operating: if not, you'll damage first the new piston and then the rest of the indicated parts. Pouring oil in the engine will start circuit 2 only.

Follow the instructions I gave or the air pressure trick from big t.

(Dr) Auke

left?