How much oil should an oil pump, pump, if an oil pump could pump oil?

[wilit]

Picked up a non running '87 Spree and I'm trying to get it back on the road. It hadn't run in a LOOOONNG time and the kid I bought it from couldn't get it running and gave up on it. Long story short, I decided to throw a new top end on it. Bought a piston and cylinder off of Amazon and figured, all those terrible reviews about out of round jugs are probably a one in a million. Well, had it soft seize on me 3 times and decided go back to the factory cylinder that's still in good shape and a piston I bought from Taz on eBay. Took the Amazon top end apart and it was d*** near dry. I thought that was weird since it was smoking when running (and smelled like 2 stroke smoke) and the original piston and cylinder seemed to be pretty well lubricated. Now I'm thinking maybe all that smoke was from the residual oil in the crankcase.

Anywhoo... Decided to test the oil pump. I pulled it off, chucked it up in a drill and spinning it at 1800rpm (max for my drill) and a microscopic amount of oil dribbles out. 1. Is this an accurate way to test the pumps function? 2A. If yes, how much oil should be dribbling out? 2B, if no, how should I test the pump?

[bonesv]

AS far as I know, the oil pump, and the lines from oil reservoir to the nipple on the intake manifold must be primed and free of any air bubbles or the motor could suffer damage. I always mix in a very small amount of 2 stroke oil in the first tank of fuel when doing break-in on a new top end. Too much oil will alter your fuel-to-air ratio which is also critical so be sure of your measurements. My un-educated guess about testing the oil pump is it either works, or it doesn't. If oil is coming out while spinning the shaft, then it should be usable. You should probably wait to hear other advice on that before making a final judgement. I believe counter-clockwise is the correct direction for spinning the oil pump.

[Meatball]

Theres a procedure explained in the service manual on how to prime the pump but Ive never used it. Priming is crucial, as Bones mentioned, to avoid running dry. What ive done to prime with 100% success is to drain the fuel tank and fill with 32:1 mixed fuel. Then pull the oil feed line from the carb (sometimes intake, depending) and run it to a CLEAR catch can. I use a simple empty water bottle with liberal amounts of tape to keep the hose securely in the bottle. REMEMBER to cap off the oil bung on carb/intake! Then mount the bottle (with oil line affixed) someplace with bungy straps, tape, wire, etc to be sure it stays put. Then simply ride it around a bit until theres a good amount of oil collected in the bottle.

At this point, I know the pump is working and all air pockets are purged. Reattach the oil line in the proper bung, drain mix fuel and add straight gas. Dump catch bottle into oil reservoir.

As Bones suggested, either the pump works or it doesnt. Ive watched the flow amount from the oil line and its very minuscule. Almost seems to ooze out in pulses rather than constant flow. It flows so slow that if you had even a ONE INCH air bubble in your line, your scoot would likely see several minutes of runtime without oil. Certainly long enough duration to cause terminal damage.

[eclark5483]

As previously stated, you'll wanna run extra oil in the tank when breaking in a new piston, standard or BBK. The problem with the Amazon kits aren't that they are out of round, the problem is with the rings which are typically junk. Easily remedied by buying a set of Honda brand rings which are still available online or from your local Honda dealer for about $20 I believe. As for how much extra oil to add, well, you mentioned 2 types, regular and BBK. I can't honestly speak from experience on the regular cylinder, but I can tell you what worked for me using dyno analysis on the BBK with oil pump. I ran 80:1 extra in the tank for 2 tanks, then I switched to 96:1. This was using Honda Pro GN2 Injector oil so I can't speak of other brands. My BBK has been 100% solid and I full throttle it all the time. This is on my 87' mind you, the 86' is my son's, also has a BBK, but is ran with a deleted pump at 32:1. Now on a stock piston, you will only need to run extra oil just for break in... for you I'm guessing you'd want 80:1, maybe a bit leaner like 85-90:1. The pump runs linear in it's output, meaning, the higher it revs, the more oil it displaces. On an 1800rpm drill spinning it, only seeing a couple drops is perfectly normal but does not indicate if the lines are properly bled. On a BBK, you absolutely will want to run extra oil in the tank after break in. the stock pump can't produce enough lubrication for the bigger piston, it was only designed for 49cc and nothing higher, so 80:1 break in and 96:1 after and you should be good. The oil pump does not fail unless teeth are broken off which is pretty rare, but the ring does fail because of natural 30+ year deterioration and can lead to excess oil seeping into the crank case. If you soft seized on a stock sized piston (or even BBK), either 1 of 2 things have happened. 1, the rings are SHIIIIIT and did not allow for proper honing/break in, or 2, you have air in the oil lines causing improper lubrication.. again.. bleed the lines per manual instruction and run extra lubrication to break in the rings. Do NOT over lubricate, this will also make you run lean and can blow the piston. The Spree is very sensitive, especially when breaking in. Good luck.

[vintagegarage]

This old post has some relevance to the current discussion.. Please have a look at:

viewtopic.php?f=3&t=12364&start=90