New Oil Pump Lines for '97 XP

[grhonk]

I went to a local Power Sports shop for some new tiny oil pump lines that go from the pump to the valve housing. These new lines appear smaller than the original ones. Is it possible the original ones are so old that they have increased in size and therefore the new ones I bought are the correct size?

 

[LouDoo]

The proper size and type is 3/32" tygon fuel hose. My local ACE Hardware store carries it, it is also used for chain saw fuel line. Use small cable ties for clamps.

Lou

 

[Sportster-2001-951C-Stock]

I went to a local Power Sports shop for some new tiny oil pump lines that go from the pump to the valve housing. These new lines appear smaller than the original ones. Is it possible the original ones are so old that they have increased in size and therefore the new ones I bought are the correct size?

The specified ID of the new tubing should be 3/32", according to my recollection.

 

[summer]

If its smaller that 3/32 you wont even get it on the nipples. Hard enough with the correct size.

 

[Coastiejoe]

I'd be VERY hesitant to use any line that I felt is smaller than the OEM line. Oil is to critical to be screwing around with the volume.

 

[Strizzo]

I'd be VERY hesitant to use any line that I felt is smaller than the OEM line. Oil is to critical to be screwing around with the volume.

its not a high volume application, if it can flow enough fuel to supply a 50cc chainsaw, it can move enough oil to keep the engine supplied. the oil pump is a positive displacement pump, so slightly smaller lines won't reduce flow, there will just be less oil contained in the lines between the pump and injector.

 

[Coastiejoe]

its not a high volume application, if it can flow enough fuel to supply a 50cc chainsaw, it can move enough oil to keep the engine supplied. the oil pump is a positive displacement pump, so slightly smaller lines won't reduce flow, there will just be less oil contained in the lines between the pump and injector.

I am sure you are correct. I just feel that going smaller caries risks. Harder for the oil to flow, can change the pressure of the flow and or the pressure required for the oil to flow.

I could be WAY OFF, it's just a logic thing to me. But logic does not always apply,,,, LOL

 

[Strizzo]

I am sure you are correct. I just feel that going smaller caries risks. Harder for the oil to flow, can change the pressure of the flow and or the pressure required for the oil to flow.

I could be WAY OFF, it's just a logic thing to me. But logic does not always apply,,,, LOL

i agree with you that smaller lines could make it harder for the pump to move oil, but like Summer said, if its that small you're not going to get it on the fittings. i did a quick calculation of the amount of oil that would have to flow through the hoses at WOT if the mixture is 40:1, which seems to be the agreed upon ratio that the pump delivers at WOT. SO:

40:1 = 3.2oz per gallon. if the 787 burns 11gal/hr, thats 35.2 oz/hr of oil, just over a quart, or .275 gallons of oil per hour. remember that there are two lines, so each piece of tubing only has to flow half that, so each one would only be flowing half that, or .1375 gallons per hour. break that down to a per-minute number and its only .58 oz. of oil per minute total flow, or .29 oz. of oil per line per minute. you could probably exceed that flow if you just hooked the oil tank feed directly to the lines let it gravity feed.

so yeah, its a good idea to keep those things in mind, but its not likely to be an issue. the only flow rates through tubing that small i could find on the internet was for tubing pumps for use in the medical realm, and only listed 1/16" (2/32") and 1/8" (4/32") tubing. their flow rate for 1/16" tubing is listed as 110ml/min of water at 72 degrees, which is 3.719 oz per minute, so you probably have a good safety margin considering the API-TC oil is a bit thicker than water.

 

[Sportster-2001-951C-Stock]

Placing aside arbitrary comparisons, if it's 3/32 id line you have then it's good to go. If not, then find the right stuff. Tygon designed for hydrocarbons is what you want, it will last much longer than anything else. Vinyl is cheap and depending on grade won't last nearly as long.

If you do find a larger id tubing which fits the barbs snugly, then use that instead(Tygon for hydrocarbons preferred) and tell me which size you decide on using please, I'll order some and test it for myself.

When I replace my oil lines (perhaps next year, I keep tygon 3/32id tubing on hand) I'm considering to test a snug fitting o-ring over the tubing as a hose clamp instead of tie wraps.

 

[Sportster-2001-951C-Stock]

What's the measurement on your barb fittings?

For reference, 3/32=0.094, the next size up would be 1/8 = 0.125

I measured some fittings here that are 0.132 behind the first barb and 0.144 behind the second barb, these are barbed fittings designed to accept a 3/32 id tubing. I have some 5/32" tubing that is too large.

So you might try 1/8"id and see how that fits your barbs. The grade I'm using is F-4040-A Tygon, it's green.

Simple physics dictates that Flow1/Flow2 = (r1/r2)^2, thus if r1 is 1/32" larger than r2 such that (0.0625/0.0469)^2, thus flow1 is 1.78x greater than flow2

Also, this doesn't account for length and non-laminar flow factors attributable to viscosity. Is glass a highly viscus fluid at room temperature?

 

[summer]

Thanks strizzo, I have a headache now. Waaaaaaaaaayyyyyyy to technical for this brain.
Anyway I bought mine from the dealer. That way I know its the right stuff and the right size. Wasn't but 4 or 5 dollars I believe. Not worth the hassle of wondering if I had the right stuff. But that's just me.

 

[Sportster-2001-951C-Stock]

grhonk! I looked into this and found an old post by Dr. Honda:

"the small lines are 1/8" ID. Some guys use fuel line for a weed-eater, some go to the dealer and buy factory replacements, but I use 1/8" ID Tygon Fuel line. (can be bought at your local hobby shop) In reality, any gasoline stable hose is fine. And yes... you can just use Zip-ties to hold the new hoses on. If you go to a hobby shop to buy hose... do not get silicone fuel line for "Glow" fuel. It will swell up, and probably die before you make it to the water."

http://www.seadooforum.com/showthread.php?29230-Oil-Lines

So based on this it seems your observation is correct, and I'm fairly certain I don't have this particular size thus I have a new item on my list, so thanks, pal! LOL!

 

[grhonk]

This thread is an example of what I have been saying all along ... "What a great forum!" I ask one simple question and I get every angle on the subject that I could possibly need. I wish to thank all of you for contributing to this thread .. this is info I cannot get from the manual or from the dealer. I truly appreciate your input.

So far in two months on this site, I have learned about how to pull an engine, breakdown an engine, find a reputable shop to overhaul (Full Bore), fixed a fuel baffle, replaced a buzzer, anticipating new turf with yellow camo, found a great cleaning product (Super Clean) that I can use on the garage floor as well as the bottom of my hull, oil line sizes, grey fuel lines, vts fuse issues, free manual downloads, SBT, and some fantastic ski enthusiasts. Need I say any more. Thanks a million.

What I did tonight is cut a section of the old line and ran a 3/32" drill bit down its inside. It was a good fit, actually, and it fit great on the pump. Then I ran it down the new line and it was a tad bit tight, and the new tubing is hard to stretch over the pump nipple. The old end where it used to attach to the pump has been stretched to about 1/8". I then took out a 5/64" drill bit and it fit good in the new line and was a tad bit loose in the old line. Now, I'm wondering if I am just a little too anal about a 1/64" dia tube difference. Nonetheless, I will go searching for 3/32" Tygon tubing, since I think this is the correct size, however, SD built in Canada might mean the original tubing is a metric size.

 

[grhonk]

grhonk! I looked into this and found an old post by Dr. Honda:

"the small lines are 1/8" ID. Some guys use fuel line for a weed-eater, some go to the dealer and buy factory replacements, but I use 1/8" ID Tygon Fuel line. (can be bought at your local hobby shop) In reality, any gasoline stable hose is fine. And yes... you can just use Zip-ties to hold the new hoses on. If you go to a hobby shop to buy hose... do not get silicone fuel line for "Glow" fuel. It will swell up, and probably die before you make it to the water."

http://www.seadooforum.com/showthread.php?29230-Oil-Lines

So based on this it seems your observation is correct, and I'm fairly certain I don't have this particular size thus I have a new item on my list, so thanks, pal! LOL!

So, SP_Stock, I ended up selling the smaller tubing back to the Power Sports place and went to Weingardens lawn and landscaping place and bought the tygon 3/32" like Lou suggested. It's yellowish and translucent.

 

[Sportster-2001-951C-Stock]

So, SP_Stock, I ended up selling the smaller tubing back to the Power Sports place and went to Weingardens lawn and landscaping place and bought the tygon 3/32" like Lou suggested. It's yellowish and translucent.

Understood. So did you determine that 1/8"id is too large for your nipple fittings?

 

[LouDoo]

The actual hose size is metric, with doesn't exactly translate to SAE fraction. It's somewhere between 3/32" and 1/8". I have 3/32" in my three ski's and have for several years, with no problems.

Lou

 

[Sportster-2001-951C-Stock]

The actual hose size is metric, with doesn't exactly translate to SAE fraction. It's somewhere between 3/32" and 1/8". I have 3/32" in my three ski's and have for several years, with no problems.

Lou

Right. it's probably 3mm id originally, which is 0.118" 1/8" is .007 larger than original.

 

[Crofoot50]

i agree with you that smaller lines could make it harder for the pump to move oil, but like Summer said, if its that small you're not going to get it on the fittings. i did a quick calculation of the amount of oil that would have to flow through the hoses at WOT if the mixture is 40:1, which seems to be the agreed upon ratio that the pump delivers at WOT. SO:

40:1 = 3.2oz per gallon. if the 787 burns 11gal/hr, thats 35.2 oz/hr of oil, just over a quart, or .275 gallons of oil per hour. remember that there are two lines, so each piece of tubing only has to flow half that, so each one would only be flowing half that, or .1375 gallons per hour. break that down to a per-minute number and its only .58 oz. of oil per minute total flow, or .29 oz. of oil per line per minute. you could probably exceed that flow if you just hooked the oil tank feed directly to the lines let it gravity feed.

so yeah, its a good idea to keep those things in mind, but its not likely to be an issue. the only flow rates through tubing that small i could find on the internet was for tubing pumps for use in the medical realm, and only listed 1/16" (2/32") and 1/8" (4/32") tubing. their flow rate for 1/16" tubing is listed as 110ml/min of water at 72 degrees, which is 3.719 oz per minute, so you probably have a good safety margin considering the API-TC oil is a bit thicker than water.

WOW !!! I feel like I just went to math class . GREAT JOB on the explanation .

 

[grhonk]

Understood. So did you determine that 1/8"id is too large for your nipple fittings?

1/8" is not the right fit. It is too sloppy for my liking. I feel 3/32" will have less chance of falling off the nipple since it is a tighter fit.

 

[Sportster-2001-951C-Stock]

1/8" is not the right fit. It is too sloppy for my liking. I feel 3/32" will have less chance of falling off the nipple since it is a tighter fit.

The proof is in the pudding, 3/32 it is! (I'm going to test this for myself though, b/c that's how I am! LOL!)

 

[Sportster-2001-951C-Stock]

1/8" is not the right fit. It is too sloppy for my liking. I feel 3/32" will have less chance of falling off the nipple since it is a tighter fit.

Looking at your photo of the tubing fitted over the barb and assuming it's 3/32 then it's not stretched much at all. Based on this, I'd agree 1/8" is probably too large for the nipples.

 

[shagy959]

just block it off mix your gas and dont worry about the problems that come with a oil pump leave the oil tank hooked up to the the line that goes into the motor for the gear and mix your gas

 

[grhonk]

just block it off mix your gas and dont worry about the problems that come with a oil pump leave the oil tank hooked up to the the line that goes into the motor for the gear and mix your gas

Just curious .. what's your gas:il ratio? (gas-to-oil)

 

[shagy959]

i like to mix all my stuff 40:1 but if you are running to rich on the plugs could always back off to 50:1 then check your plugs again

 

[summer]

OMG there is more discussion on this than what type oil to actually use. :facepalm: Just go to the dealer and buy it and its done. You know its the right size and there is no questioning. Or if not the dealer, take the pump with you and find something that's tight on the nipple. Why block off the pump and start wasting oil just because you need more oil lines. Not trying to be a bi#ch this morning but I just don't understand why the long drawn out discussion over something so seemingly simply. I could see if it was a part that was ridiculously expensive at the dealer but it's less than $5 and you have the right stuff. Anyway, that's my take on the great oil line debate. Carry on gents! :cheers: