1997 GTX off season closed loop RV lubrication study.

[AquaEye]

Convection Current - GCSE Physics Practical.​

This is the start.
www.youtube.com/watch?v=Ph4Re3CrUmY
Have two spare 787 motors from a barnyard find. One my son shall rebuild & the other I'm going to use for numerous crazy arse experiments in RV lubrications, yes sir.
Got to construct a practical, working lab bench + a half dozen other items. Will video when I get all the ducks lined up.
Try to get it done by late April, or not.

 

[AquaEye]

So this is the basic "meat & potatoes" of the construct. Of course there will be tailored changes to product design as the study progresses.
All this is to introduce thermal difference to induce thermal convection/flow.
1ltr anodized
L X W TBD

Can be cut to length
Meh, maybe?

Order of placement within oil circuit TBD after lab bench studies.
All fitting will be 8AN with the option of changing to lessor to accommodate a smaller dia hose if warranted. (static line pressure considered)
All this to knock tank temps down as much as possible w/o compromising too much "real-estate"(?)

 

[WhiskeyD]

What are you trying to accomplish by circulating the oil? If there was a need to circulate and/or filter oil, then an oil pump would have been included decades ago. These are old engine designs and the oil bath works fine.

 

[AquaEye]

What are you trying to accomplish by circulating the oil? If there was a need to circulate and/or filter oil, then an oil pump would have been included decades ago. These are old engine designs and the oil bath works fine.

"Trying to accomplish"?
No try to it. It will occur.
What you consider "fine", I do not.
I can because I can, it's a free country.
Cancel elsewhere.

 

[WhiskeyD]

I didn’t realize we had a genius here that’s knows more than the BRP engineers

 

[AquaEye]

Trivial FYI capacity observations using XPS 2T syn oil.
1 ltr
830.9 gr
29.3 oz
1.83 lbs
12mm OEM line @ 18"
36.3 gr
1.28 oz
.077 lbs
Aftermarket oil filter
18 ml
14.8 gr
.525 oz
.033 lbs
3/8 line @ 12"
15 ml
15.0 gr
1/4 line @ 18"
13 ml
10.3 gr

 

[dougamclean]

"Trying to accomplish"?
No try to it. It will occur.
What you consider "fine", I do not.
I can because I can, it's a free country.
Cancel elsewhere.

I don't think Whiskey is trying to cancel you Aquaeye..just attempting to understand what you are building and it's desired effect, as am I.

Can you explain the experiment for the rest of the class??

Could you diagram your working model and how the components fit? And what are the old seals for?

 

[dougamclean]

I didn’t realize we had a genius here that’s knows more than the BRP engineers

I think Aquaeye is an 'outside the box' experimentalist.

An experimentalist builds strictly with function and performance in mind...willing to challenge the standard practice to add back the durability or performance the engineers left on the table in order to save in materials cost or simplify for mass manufacturing.

We all know history has a hundred examples of design issues engineers either didn't see or chose to overlook!!

The aftermarket is rife with add-ons for all manner of machine to make something out last or out perform standard engineering design...most are created by non-engineer, DIY types!!

 

[AquaEye]

I don't think Whiskey is trying to cancel you Aquaeye..just attempting to understand what you are building and it's desired effect, as am I.

Can you explain the experiment for the rest of the class??

Could you diagram your working model and how the components fit? And what are the old seals for?

To be revealed on the video in late April.
But I can tell you this much, this is not an experiment. This has already been applied to the aviation Rotax's by a few enthusiast.
Their advantage is they have the luxury of air cooled real-estate. Huge temp differential, ample flow/circulation.
Where as I, do not.
This works. It's proven, actionable science.

Convective Heat Transfer in Fluids | Efficiency, Factors & Applications

 

[AquaEye]

Little late on posting progress but life gets in the way sometimes.
Seals came in, using 1.25 expandable plugs, snugged but still able to turn. Using 1of the 3 engines from the "barnyard find".

Applied 3 bond 1211 with roller paying attention to amount applied, skim thin, or so I thought. Applied to only the surrounding RV cavity.

Imo, this is too much "squeeze out".

The highly polished roller worked against a uniform application. Too much slip & slide. Going to put some tread on the roller with sandblaster & see if application becomes controlled & predictable. Takes some practice, I reckon.
Heat sinks came in a couple days ago. Next hurdle, weld 1/4-20 studs to tank to secure HS's. Probably have to re-engineer lab bench. Right now it, looks like Jethro threw it together.
The stud sticking out of RV shaft? Got's to have rotation during lab bench run.
Later.....

 

[K20017]

Why so mysterious? Why can't you just explain what you are doing without some mad scientist preamble suspense theory you've concocted after watching a few youtube videos on fluid mechanics? What's next, you are going to re-engineer the wheels on your trailer?

 

[AquaEye]

Why so mysterious? Why can't you just explain what you are doing without some mad scientist preamble suspense theory you've concocted after watching a few youtube videos on fluid mechanics? What's next, you are going to re-engineer the wheels on your trailer?

Read the entire thread & discern, smartass.

 

[WhiskeyD]

Read the entire thread & discern, smartass.

Why wont you answer a simple question? Is it because you have no idea what you are trying to achieve besides create more leak points and things to break?

 

[WhiskeyD]

Are you trying to circulate the oil and cool it somehow? Do you think the oil bath temps cause premature wear? The whole "All this is to introduce thermal difference to induce thermal convection/flow" doesnt make sense inside of a hot boat hull.

 

[AquaEye]

Little late on posting progress but life gets in the way sometimes.
Seals came in, using 1.25 expandable plugs, snugged but still able to turn. Using 1of the 3 engines from the "barnyard find".
View attachment 69335
Applied 3 bond 1211 with roller paying attention to amount applied, skim thin, or so I thought. Applied to only the surrounding RV cavity.
View attachment 69336
Imo, this is too much "squeeze out".
View attachment 69337View attachment 69338View attachment 69339View attachment 69340View attachment 69341
The highly polished roller worked against a uniform application. Too much slip & slide. Going to put some tread on the roller with sandblaster & see if application becomes controlled & predictable. Takes some practice, I reckon.
Heat sinks came in a couple days ago. Next hurdle, weld 1/4-20 studs to tank to secure HS's. Probably have to re-engineer lab bench. Right now it, looks like Jethro threw it together.
The stud sticking out of RV shaft? Got's to have rotation during lab bench run.
Later.....

After cure, split case & it is inside as it was on the outside, entirely to much "squeeze out". Unacceptable. The 1211 did as intended, filled in two areas that had indentations/pit but the rest of the mating surface was completely devoid of 1211. Testament to precise machining @ Rotax. Blasted roller to give it some tread, & will apply even less 1211 to roller & let the weight of roller(.57lbs) dictate application thickness.


Sorry, no pics to validate this event so take it with a grain of salt..

 

[AquaEye]

Interesting observations of the RV helical gear contact patch.
One of 3 1996/97(?) Rotax 787 from "barnyard find". Unknown hrs but Pistons/cylinders suffered no major damage. Measurements jive with OEM factory specs with nominal wear. Spit balling here but I figure 150>170 hrs(?) Hell, I don't know.
Don't know if this is considered good, bad or ugly in the Rotax universe but it is what it is.

 

[shamrock246]

Interesting observations of the RV helical gear contact patch.
One of 3 1996/97(?) Rotax 787 from "barnyard find". Unknown hrs but Pistons/cylinders suffered no major damage. Measurements jive with OEM factory specs with nominal wear. Spit balling here but I figure 150>170 hrs(?) Hell, I don't know.
Don't know if this is considered good, bad or ugly in the Rotax universe but it is what it is.

The pattern looks to be to the right I guess it doesn’t matter that much in this application,I’m guessing they spring loaded it absorb torsional shock.

 

[AquaEye]

The pattern looks to be to the right I guess it doesn’t matter that much in this application,I’m guessing they spring loaded it absorb torsional shock.

My son "donated" this motor for me to play around with. He has two more that he hasn't cracked open yet but when he does, I'll be in the way with camera in hand so as to do comparisons. One motor he squirreled away has a known hrs of 250+. The motor I'm currently rebuilding (40.3 hrs) has yet to have RV gear pictured but it will happen & posted.

 

[AquaEye]

My son "donated" this motor for me to play around with. He has two more that he hasn't cracked open yet but when he does, I'll be in the way with camera in hand so as to do comparisons. One motor he squirreled away has a known hrs of 250+. The motor I'm currently rebuilding (40.3 hrs) has yet to have RV gear pictured but it will happen & posted.

More observations.
The top 4 pics are also from a craft of unknown hours used in comparison with the bottom pics from the previous post.
Some differences in contact patch's but nothing that I would consider detrimental....I think.
Have yet to add pics of the 250+ hrs & the 40.3 hrs motors for those comparisons.

 

[AquaEye]

More observations.
The top 4 pics are also from a craft of unknown hours used in comparison with the bottom pics from the previous post.
Some differences in contact patch's but nothing that I would consider detrimental....I think.
Have yet to add pics of the 250+ hrs & the 40.3 hrs motors for those comparisons.
View attachment 69415View attachment 69416View attachment 69417View attachment 69418

RV gear @ 40.3 hrs.

 

[AquaEye]

Lab bench study mixed with positive & negative results, some questions answered. Part 1
*Engine mounted @ 46.3 deg.
*1/2" hose.
*1/2" x 3/8" x 1/2" tee.
*Imusa 1,100 watt electric single burner.
*DEI heavy Duty floor & tunnel shield reflective heat barrier.
*Kaiweets optical ind tach.
*Teslong borescope.
*Adam compact balance.
*Racetronix 1 ltr catch can, 8AN ( TANK-CT1L8B)
*Racetronix Shut-Off Valve, 1/4-Turn Ball, -8 AN ORB & JIC Female ( SOV-6208).
*XPS E-Tec 2T.
** The 4 finned heat sinks are to be applied to tank along with the "spur" of air current after rebuild/install.
I've got the real-estate to do so.
*** Take note of the orange & green lines on tank back board. Be aware that the parallax observational error mis-represents.
Green in line with supply barb while orange in line with return barb.
The 1st 6 pics are W/O CCW gear rotation & externally heated case/oil.
Fluid finding its own level is showcased. Oil level in tank height relative to oil level in RV cavity
Tank oil level purposely moved "just above" RV cavity level.
The "witness" 3/8" hose tee is located 1" BELOW tank opening.
I underestimated what I thought should have occurred, the flow was rather robust, nice surprise though.

 

[AquaEye]

Lab bench study mixed with positive & negative results, some questions answered. Part 1
*Engine mounted @ 46.3 deg.
*1/2" hose.
*1/2" x 3/8" x 1/2" tee.
*Imusa 1,100 watt electric single burner.
*DEI heavy Duty floor & tunnel shield reflective heat barrier.
*Kaiweets optical ind tach.
*Teslong borescope.
*Adam compact balance.
*Racetronix 1 ltr catch can, 8AN ( TANK-CT1L8B)
*Racetronix Shut-Off Valve, 1/4-Turn Ball, -8 AN ORB & JIC Female ( SOV-6208).
*XPS E-Tec 2T.
** The 4 finned heat sinks are to be applied to tank along with the "spur" of air current after rebuild/install.
I've got the real-estate to do so.
*** Take note of the orange & green lines on tank back board. Be aware that the parallax observational error mis-represents.
Green in line with supply barb while orange in line with return barb.
The 1st 6 pics are W/O CCW gear rotation & externally heated case/oil.
Fluid finding its own level is showcased. Oil level in tank height relative to oil level in RV cavity
Tank oil level purposely moved "just above" RV cavity level.
The "witness" 3/8" hose tee is located 1" BELOW tank opening.
I underestimated what I thought should have occurred, the flow was rather robust, nice surprise though.
View attachment 69456View attachment 69457View attachment 69458View attachment 69459View attachment 69460View attachment 69461

The 2nd 5 pics are WITH CCW rotation & externally heated case/oil.
BIG disappointment. My "expectations" totally blown out of the water.
The single burner could only muster 110 deg @ the case W/O the FIRE MARSHALL becoming involved.
I could only achieve around 91/93 deg oil temp. The incoming oil was @ 75 deg.
Temperature differance introduced but w/o the intensity of higher temps, convection is "less than".
With RV gear @ 1,900 rpm, I expected the helical gear to take flow to the next level & pass the finish line so as to overcome
that "1" BELOW" deficit with authority..Didn't happen.All that occured was a "trickle" return.
Made a vid of the whole circle jerk but opted to post the snapshots because the Johnnie Walker wisdom compels such.
The only way to validate this RV oil circuit is to take it to the lake.
NEXT: EGT.