Accusump / Oil pressure advice

[Coz]

I know that Don. Thank you actually for looking out.
Sometimes the simplest things can be missed.

It's been a busy week...But I will get to moving that bracket soon
Lot to get done by Jan 14th...

http://nsxprime.com/forum/showthread.php?p=1513771#post1513771

First event for the NASA-AZ new year. Points you know

If you see anything you think I missed, always say something.
It happens at my age.......

Not trying to give you a hard time.
Ideally both sides. They should be as close to the end cap as possible.
I have mine mounted in the trunk at the same spot. I was able to get both clamps at the ends.

Good Luck.

Later,
Don

 

[Coz]

Hrant,
Best piece of advice I can give you...MOVE IT !...I spent 3 years crawling under my car reading and servicing it.

When getting down gets as hard as getting up, it's easier to deal with in the trunk :wink:

Trust me on this :biggrin:

Coz and Don, good feedback. I'll ask Shad to test these. Also, this quote caught my eye: Keep the dust cap on the air valve to prevent the introduction of dirt into the air end of the unit.

Not sure if the dust cap is on or not. If not, perhaps enough dirt is flowing from the oil cooler to get into the air valve? Since the Accusump is mounted inside the fender, I have to jack the car, take the bottom fender covers from under and then do all the readings ...... at my age, my bones like this to be done on a lift :tongue:

 

[Canton_Nick]

I have been having some problems with my Moroso valve (with electric start hook up at the cruise control). Recently, it has leaked and Shad twice tried to clean it up - something seems to cause it to block the flow/pressurizing (occasionally) and yet again, this just after some 150 miles it did it again!

When fully operational, I can hear the valve open and the pressure starts at about 25 psi when dumping oil. When it is temperamental - after sitting for a week or two, you hardly hear the valve open and the pressure is just about 5-7 psi. So I guess it must be losing pressure (set at about 60-65 psi) and leaking since I see oil in the fender liner and the floor behind the rear tire - the Accusump is located inside the rear fender.

I too heard the issues with the previous Canton valves, if the newer Canton valve is "now" the better valve, perhaps it is time to swap this headache ..........

After getting off of the telephone with you a few minutes ago i decided to read back through this as you sent me a link and I think i may have a solution to this issue.

When we spoke I walked you through a leakdown/precharge reset test. The precharge is supposed to be at around 7-10 psi of air pressure with NO oil in the unit. (basically if the accusump has 7-10 psi of air on the air side and the oil starts to pressurize the sump, it will double that 7 psi as the piston gets pushed back further into the sump compressing the air so the accusump can always have a positive charge to discharge the oil.)

You have stated that you guys have 60-65 psi in there. I may be mistaken and you may have 65 psi in the unit when the vehicle is running and the precharge is correct BUT if you have 65 psi of air pressure with no oil and you start that vehicle, the 65 psi is going to double and triple causing the unit to act like it is hydraulically locked. That will cause the pressure relief valve to release oil as a safety precaustion because the pressure in the accusump is well above its rated pressure.



Just as a note i will walk through the leakdown/reset precharge procedure. Anyone who may be having similar issues may want to give this a look as well because it may solve some un answered questions.

1. Open the accusump valve with the vehicle OFF. (if using an electric style valve, power the vehicle on but do not start the engine)

2. Pressurize the air side of the accusump to 80 PSI. Double check with a tire gauge to ensure the gauge on the accusump is accurate.

3. Let that sit for 60 second to ensure that the accusump is free of any oil or fluids.

4. Double check the pressure and adjust back to 80psi if any pressure was lost due to trapped oil.

5. Let the accusump sit for 24 hours without starting the vehicle. (You may have the valve powered off at this time)

6. After 24 hours, return to the accusump and check to see if the pressure in the gauge is still at exactly 80 PSI. If it has dropped even 1 PSI, you may have a small air leak inside the unit or at the gauge etc. This must be tracked down before the accusump can be used again otherwise the unit will slowly leak out the precharge and will not serve it's purpose.

7. If the accusump has not leaked any pressure, we will reset the precharge. To reset the precharge all you have to do is release air pressure until the gauge reads 7-10PSI. Double check with a tire gauge to check gauge accuracy.

8. Finally, with the valve in the OFF position, start the vehicle and let the accusump pressurize.

Now the accusump is 100 ready for use again and should hold air pressure.


hope this helps.

 

[nsxnut]

Hrant,
Best piece of advice I can give you...MOVE IT !...I spent 3 years crawling under my car reading and servicing it.

When getting down gets as hard as getting up, it's easier to deal with in the trunk :wink:

Trust me on this :biggrin:

I agree... I like to be able to look at the gauge and make it easy to service.

Ideally you would like to have the Oil side of the accusump lower than the pressure gauge side. Mounting in the wheel well allows this.

Mounting in the trunk it will be horizontal. I was able to get a slight angle but not much.


> perhaps enough dirt is flowing from the oil cooler to get into the air valve?
Hrant: The dust cap prevents you from getting dust into the air side of the accusump any time you are adding air to the unit.

 

[Hrant]

Nick, thank you for the post; the steps are quite helpful.

I believe my issue has been a leak which I think we finally located it to be the pressure release valve/nut. As a trial test, Shad put a bolt to seal it and for now it seems to work as there is no noticeable leak and pump does seem to work dumping oil at about 20 psi reading.

If the issue is the pressure release valve, I assume that part is available? Also, since the max oil pressure under full boost is about 70 psi (others may have other readings but I doubt any over 100), is the pressure release valve that critical since the Accusump is rated at 175 psi?

When fully pressurized - ie with oil in the Accusump, the reading on the Accusump gauge is 70 psi which is consistent with what the manual recommends. I have forwarded your post to Shad for his reference; I believe he followed those same steps as well.

 

[nsxnut]

Nick, thank you for the post; the steps are quite helpful.

I believe my issue has been a leak which I think we finally located it to be the pressure release valve/nut. As a trial test, Shad put a bolt to seal it and for now it seems to work as there is no noticeable leak and pump does seem to work dumping oil at about 20 psi reading.

If the issue is the pressure release valve, I assume that part is available? Also, since the max oil pressure under full boost is about 70 psi (others may have other readings but I doubt any over 100), is the pressure release valve that critical since the Accusump is rated at 175 psi?

When fully pressurized - ie with oil in the Accusump, the reading on the Accusump gauge is 70 psi which is consistent with what the manual recommends. I have forwarded your post to Shad for his reference; I believe he followed those same steps as well.

Your pressure gauge is only showing you the average pressure.
The measurement point is off of the cylinder head. The accusump is connected to the output of the oil pump.

There is a phenomena hydraulic shock. If this occurs the pressure can be considerably higher. If for some reason the Piston was stuck or the accusump was completely full with oil the unit could burst without the pressure relief valve. I would try and get a replacement as soon as you can.

http://en.wikipedia.org/wiki/Water_hammer

 

[Canton_Nick]

Also, one thing i never asked is if you had the pressure relief valve teflon taped?

We leave that loose when we ship the accusump so you could install the valve. We dont recommend using pipe dope as it could leak.

Nick, thank you for the post; the steps are quite helpful.

I believe my issue has been a leak which I think we finally located it to be the pressure release valve/nut. As a trial test, Shad put a bolt to seal it and for now it seems to work as there is no noticeable leak and pump does seem to work dumping oil at about 20 psi reading.

If the issue is the pressure release valve, I assume that part is available? Also, since the max oil pressure under full boost is about 70 psi (others may have other readings but I doubt any over 100), is the pressure release valve that critical since the Accusump is rated at 175 psi?

When fully pressurized - ie with oil in the Accusump, the reading on the Accusump gauge is 70 psi which is consistent with what the manual recommends. I have forwarded your post to Shad for his reference; I believe he followed those same steps as well.

 

[nsx2tall]

Canton_Nick you have PM

 

[Hrant]

A quick update. After a few more tests, and changing the pressure gauge to the upgraded liquid filled Canton 24-500 (they no longer offer one with red numbers irrespective of what is in most websites!), we have determined that there are at least two leaks - so far.

First - and I learned this the hard way, DO NOT clean standard pressure gauge with any solvents except perhaps damp cloth. The fascia is plastic and it will get immediately pitted/deformed. The upgraded gauge has a glass cover and frankly it is much easier to read especially if your Accusump is in inside the fender.

(1) Oil is leaking in the "air" chamber. This means the O rings are worn out or damaged. This was the initial diagnosis by Shad last year when we started checking for the leak but we were advised to pursue other tests first since an internal leak was not common. After four visits to the shop, we determined this to be indeed "one" of the leak sources in the drop of pressure after taking the air pressurizing valve out and saw yellow oil seeping out - about a tablespoon max. We cleaned the interior thoroughly and inspected it with a probe to make sure. Pressurized it again to about 75 psi and by next day the pressure had dropped by 7 psi.

It is now holding at 62 after 48 hours but ......

(2) Even after initially finding a leak from the pressure release valve, plugging it to further test, there is still some oil seeping - visible at the bottom billet cover, and drippings on the fender bracket/nuts - this even though all the fitting are tight and the Accusump seems otherwise clean! And yes we have used Teflon to all the fittings. Unless it is leaking from the pressure valve itself (we did not put a cover cap on it); but the valve looks dry and the oil drip trace is not under it.

This has been an arduous and frankly quite an annoying chase given the amount of time that Shad and I put to address it.

I have talked to Nick at Canton who has been always eager to help and resolve this issue. We are sending the unit to Canton for further investigation. Perhaps all it needs is maintenance as in replacing the O rings; they do offer a higher grade O ring called Viton which meets aerospace standards for heat/durability. I would definitely opt for that and avoid this hassle. Perhaps there is more damage internally too because of the failure of the O ring gouging the inside wall ...... we shall see.

My recommendation to you that have 2-3 year old Accusumps - and especially those who track, check your pressure gauges even if you do not see visible oil leak. If there is a drop in pressure overnight, first look to see if there is a leak in the "air" chamber which would show colored oil (they do put some clear lubricant for the piston that would not be an internal leak). Make sure you bleed the air first ..... :wink:

 

[nsxnut]

My recommendation to you that have 2-3 year old Accusumps - and especially those who track, check your pressure gauges even if you do not see visible oil leak. If there is a drop in pressure overnight, first look to see if there is a leak in the vacuum chamber which would show colored oil (they do put some clear lubricant for the piston that would not be an internal leak). Make sure you bleed the air first ..... :wink:

There is NO vacuum chamber. Both chambers are pressurized.
The piston moves back and fort to maintain equilibrium between the two sides.
Once the accusump is charged with oil the pressure gauge reading should be your oil pressure at the accusump.

To test the piston orings open the oil valve with the motor off "empty the accusump of oil" and than pressurize the Air side.
It should not loose any pressure over time. There is a procedure to do this on Canton site.

 

[Hrant]

There is NO vacuum chamber. Both chambers are pressurized.
The piston moves back and fort to maintain equilibrium between the two sides.
Once the accusump is charged with oil the pressure gauge reading should be your oil pressure at the accusump.

To test the piston orings open the oil valve with the motor off "empty the accusump of oil" and than pressurize the Air side.
It should not loose any pressure over time. There is a procedure to do this on Canton site.

Don, don't be a smart alec :wink:

I am sure you understood my post - yes its the air chamber (my bad not vacuum). But we have done those tests that you describe and that was our first diagnosis when we called Canton last year and were advised otherwise. Shad is not a newbie. That still doesn't explain the actual leak source to the outside.

 

[nsxnut]

Don, don't be a smart alec :wink:

I am sure you understood my post - yes its the air chamber (my bad not vacuum). But we have done those tests that you describe and that was our first diagnosis when we called Canton last year and were advised otherwise. Shad is not a newbie. That still doesn't explain the actual leak source to the outside.

I understand.

To check the pressure relief valve may you could get some clear tubing and slip that over the valve. If it leaks the oil will be on the inside of the tube.

Sounds like sending it to canton is the best.

Later,
Don

 

[Hrant]

Canton Racing tested my Accusump and indeed they found the inside O ring to be the culprit for the leak - causing a drop in the pressure overnight, as well as leaking outside the canister from the bottom. There was no internal damage or gouging of the wall which is the good news

They have refurbished it with new Viton O ring and on its way. Hopefully this is the end of it.

-----

Now for those of you who have had an Accusump for some years, you may want to consider replacing the O ring as a maintenance issue (they do state that in their manual .....) before you start seeing soaked oil on your carpeting especially if you have placed it in your daily driver trunk:tongue:

 

[NSX1145]

It defiantly sounds like your getting some pressure loss somewhere in the system while it sits. As you know, even as it sits the Accusump still holds pressure, or it should anyway as a closed system.

So when you shut the car down, the Accusump is at 80 to 90 PSI, correct ?
Then after it sits for a week or so, where's the pressure at before you start the car ?

Sure sounds like a fitting some where that's leaking Hrant and with the constant pressure from the Accusump pushing the oil out while it sits somewhere between the Accusump itself and the valve.
If the valve was stuck open, there would be no pressure in the Accusump and all the oil would end up in your pan when it's not running since that's where it would drain to.

Could be wrong, but a fitting some where would be my guess.

I just relocated my set up.

Coz,

care to share some insight to what you have for your oil supply system here? I'm doing some research into a few options like this for my own project. (Still learning)

 

[Coz]

I actually took my Accusump out of the car.
Now I run a 8 qt oil pan and a Laminova oil to water cooler.
With the pan, oil cooler and lines, I have about 10 quarts of oil in my car circulating.
If I can't catch a oil pressure problem at this point, the accusump wouldn't matter anyway and its just more weight and something else to deal with more added lines.

Coz,

care to share some insight to what you have for your oil supply system here? I'm doing some research into a few options like this for my own project. (Still learning)

 

[jones83]

[MENTION=4034]Coz[/MENTION] What oil pan are you running, and do you have pictures of your oil cooler setup with te Laminova oil to water cooler? I'm going the same rout and would love some insight in how you have yours setup.

 

[Coz]

I run the extended 8 quart oil pan, which by the way I am having some made as I type this ;-)
My Laminova set up is in the trunk.
Nick Frunzi recently had his done and it was put in the front trunk area right off the radiator tube, which is a better alternative.
Mine was done a long time ago before we started playing with other locations for it.

 

[jones83]

I feel initially hesitant to put the laminova in the front due to having to run oil lines to the front of the car. I would rather figure out a way to keep it in the rear. I've been thinking of using it in my w2a system, but I don't know how much it will affect the temps.

 

[Coz]

Thats why I ended up doing mine the way I did. Didn't want that much oil line.
I run the MASIV radiator with dual Spa fans.
30 minute session on track, my water temps never go above 214 on 100+ degree days here in Arizona.
80 to 90 degree temps, I usually run under 180 water temp and 220 oil temp on track.

I feel initially hesitant to put the laminova in the front due to having to run oil lines to the front of the car. I would rather figure out a way to keep it in the rear. I've been thinking of using it in my w2a system, but I don't know how much it will affect the temps.

 

[jones83]

Your using the largest Mocal oil to water cooler it looks like from the pic. I have been going back and forth on whether it is a good idea or not. I think finding a spot for the cooler and upgrading the radiator is the best option for me since my passenger vent is already being used.