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Oil pump fried or oil too thick?

2102 Views 10 Replies 6 Participants Last post by  badspeed
I am embarrassed about having such a dumbass question as my first post here. 2006 YP400V that I just rebuilt the top end after bent inlet valves. Can't get oil to the top bleed bolt. Engine has done > 50,000 so I filled it with 50/50 10W40 and Lucas oil stabilizer. Waited the obligatory 60 seconds but no oil. Back fed oil (10W40) down the bleed hole but no oil. Is the oil too thick or is the oil pump fried? Just trying to avoid pulling off most of the right hand side of the engine to get to the oil pump. OK let me have it!
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Maybe the passage is plugged?
Thanks for the reply Max! So if an oil passage is plugged I may have to take off the oil pump anyway?
I'm going to drop the thicker oil today and go with just straight 10W40 to see if that works. I also noticed that the o ring was missing from behind the oil filter. Not sure how important it may be but I'll be installing one of those as well.
I can't see why you would use that much additive of any sort in the oil. Personally, I'd have just used the oil straight out of the bottle at least until I had established oil flow. I don't know just what the oil bleed bolt looks like, but is there any way you could attach a vacuum source to the opening and try to pull the oil up through the passage? That might help establish whether the passage is clear. If the oil can be sucked up through the passage, but the pump won't push it up, it may help localize the problem.
Thanks for the advice Charon. I have successfully used this type of oil stabilizer to quieten down high mileage engines and avoid "dry start-ups" for over 35 years. I have not seen a schematic for the engine's lubrication system but it seems that the bleed bolt is near the end of the line just before the oil drips down onto the cam gear. So I do not think that I could pressurize the line back down into the pump to try and clear a suspected clog. All I would accomplish is filling up the cam area and spilling down to the crankcase through the cam chain gallery.
You could remove the valve cover and start the engine. If you did that and oil was flowing you get oil all over every thing, I know it for a fact too. Possibly the screw/line is blocked but if getting oil to valve train your probably good to go. In the manual they do have something about getting a prime on the pump.

Years ago a friend of mine who rebuilt transmissions had a can of stp with a little brush in it and would coat all moving parts with it to avoid dry starts.
This is, of course, personal opinion. I think the whole "dry start" thing is a myth. The oil DOES NOT all drain down into the crankcase leaving the engine dry. If you doubt, go to any auto salvage yard (junkyard). Look for a car with a tree growing up through it, which proves it has been there a LONG time. Pull the valve cover off, and note that the valves and rockers are still oily. To me, that is convincing evidence that the oil doesn't all drain back into the sump leaving everything dry.
That's what I was referring to. The Oil Bleed Bolt might be plugged.
Why 50% Lucas??? 20% is supposed to be max. amt.
I struck gold!!! Well, almost!
I took off the right hand engine cover (Alternator) and found gold flakes. I'm assuming it may be Phosphor Bronze from the oil pump shitting itself. The rest of the engine seems tight, so I'm hoping its not a bearing surface somewhere. Obviously the previous owner had done more analysis of the engine stoppage than he was willing to admit. The clues being :- the oil filter had its o-ring missing and the oil stainer was out of the bike!
So here's the part where I have to come clean and admit to stupidity in the extreme (I really am doubting that you all will want me on this forum once you hear)
In attempting to remove the alternator rotor from the crankshaft I mangled the end that sits inside the outside support bearing. And still didnt get the f-------- rotor off to look at the oil pump.
OK I know I'm screwed, and you have every right to make jokes about it, but just how far up s----- creek am I?
Bowed in shame,
for what its worth, I know response is a little late, but I kept up with oil changes and never removed the big hex head bolt with the spring and screen untill the other day. and there was so much crap in there about a two foot long string of silicon and black steel bits gold bits copper bits and a washer sitting in the bottom of that. I beleive it to be all from break in process I ride two up in the mountains and up steep grades often and a year ago started delivery on it putting about 200 miles a day. and since cleaning that out never saw a speck or unidentified floating object again at 28,000 now and a little worse for the wear but they are not meant for delivery vehicles but shes taking it.

2005 YP400T
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