Mocal Easy Clean oil tank dimensions

[bsimon]

Anybody have a 6.3 quart Mocal Easy Clean DS tank that could be measured? I'm looking for the maximum OD over the clamp that holds the two halves together. Think and Pegasus show the tank being 6.5" in diameter, but this is rather ambiguous as I'm not sure if it's the absolute MAX dimension.

 

I'm reconnoitering the removal or trimming of the victim's foot well to make room for a DS tank in my car as well as Alaskossie's new Duratech installation. Needless to say, space is at a premium in both chassis.

[Birkin42]

I can't help you with dimension on the Mocal tank.

I am dry sumping my S2000 engine and went with a custom Peterson tank. By custom I mean they started with one of their standard tanks and allowed me to dictate the size and location of all the fittings as well as the location of the add on extrenal vent/overflow tank and breather. To boot, the cost of the complete tank and breather was cheaper then the Mocal tank you are looking at. They didn't charge anything extra for the custom since they make all tanks to order anyway.

It took a few weeks to get, but the finished part looks great. They do really nice work.

I went with their 7" drag tank which seemed to fit perfect in front of my shorted passenger foot well.

They offer a large range of tanks so you should be able to find one that works for you.

Their catalog isn't too great for dimensions, but I believe you can get most of this off their web site or you can contact them direct.

[bsimon]

Jack,

 

Thanks for the tip. :thumbs:

 

I called Peterson and found an acceptable off-the-shelf tank. If I deal directly, the tank is $304 plus $52 for clamps. That's 40 bucks cheaper than the going rate for a Mocal with no clamps.

 

The engineer I spoke with mentioned that the Peterson tanks don't have the O-ring issue that made the Mocal "Easy Leak" tank so famous. The tank still splits at an O-ring, but he claims they never have complaints about leaking.

 

The overall diameter is 8" and overall height is 15.5". The tank split clamp is only 7" not counting the pinch bolt.

 

 

[Birkin42]

Didn't know Peterson had an 8" tank. My catalog only shows a 6, 7 & 9" diameter tanks but my catalog is not the latest and greatest. I think their diameter spec's are for the OD of the body of the tank and not the max OD. Maybe what you are calling an 8" tank is the same as my 7" tank?

Peterson seems to use 2 styles for a joint to split the tank. My 7" tank uses a bolt together joint. It looks like Mocal uses some kind of a band clamp that I'm guessing pinch the O-ring. The flanges are fully CNC machined and look like they do a good job of sealing their tanks. I believe they are slowly coverting all their new tanks to this style.

Wait unitl you look inside. They definitely put a lot of technology into controlling the oil flow in the tank.

The cost for my tank including breather was about the same $300 with the mounting brackets being extra. I thought this was a pretty good value especially for a made to order tank.

 

Jack

[bsimon]

As you suggest, their tank sizes are based on the OD of the spun body, in this case 6". The 8" dimension takes into account the pinch bolt and the inlet fitting. The band clamp's basic OD is 7"

 

I see there is a light weight 1.5 gallon tank with the bolted split. I'm going to call them back an see about the one.

 

[bsimon]

Here's the poop on the Peterson "lightweight" oil tank.

 

The lightweight and drag tanks have a bolted split that replaces the standard band clamped split. The tank construction is identical in every other way, including material thickness. The 1.5 gallon bolted split tank is 14 oz. lighter than the clamped version. All the ports are male AN fittings in the lightweight version. The clamped version uses female AN o-ring ports.

 

The only downside I can see to the 6" lightweight tank is they only have 6 bolts at the split. There would be less choices on how one could clock the inlet and outlet.

 

Peterson said they will add another vent fitting to the lid for $30.00. Current lead time is one week.

[Birkin42]

My 7" drag tank has an 8 bolt flange.

If clocking the fittings are a concern, why don't you specify their locations when you order. As long as you keep the inlets (near the top) tangential (to promote swirl and keep the oil away form the central beather pipe) I think you can pretty much get them to put the fittings wherever you want. I did that with mine for no extra charge. I even had them upsize the outlet to the pump to the next size up fitting for no extra charge.

I have a CAD model of the 7" drag tank that I bought. I created this to help explain to Peterson exactly what I wanted. It is relatively accurate as I adjusted the sizes to actual once I recieved the tank. The model is in SolidWorks but I can also send it as a 2D AutoCAD dwg or pdf of the drawing. Thought it may be of interest or could help.

[bsimon]

Thanks Jack,

 

I'll take you up on that. Solidworks files are fine.

 

YHM

[Birkin42]

I just emailed them to you.

If you don't recieve them or need me to use your ftp site, let me know.

[RDROCKT]

Hi Gents,

If I can jump in here, I would like to ask a couple of questions.

I am dry sumping my S2000 engine as well. I'm not sure that I have selected the right sized tank and would ask what criteria you are using to determine this. Also, how about the size of the pump, # of stages and diameter of the lines.

At present I am using AN-12 lines for all scavenge, pressure and vent lines. The pressure regulator bypass is AN-10. I am using a 4 stage Aviaid pump with a 1.5" pressure stage. What would you recommend for the scavenge stage(s) sizing?

The tank is a 17.5" tall, 6" diameter (7.5 quart) with AN-12 return inlets and supply outlet. The stock vent holes on top are 3/8" NPT that I have relocated and opened to an AN-12 fitting.

Have you been able to test your system on the track?

I have an old version of Solidworks so your drawings may not work; could you send a PDF of your tank?

Thanks

[Birkin42]

Chuck,

 

Just to start off with, I have purchased all the dry sump parts for my car, but I am now where near having it running or on the road yet, so what I am doing is not proven. I think I've done my homework so I think it should work out, but time will tell.

 

I am using a Peterson 3 stage pump, 1 pressure & 2 scavenge. Both scavenge sections are for the oil pan. I have no plans to directly scanenge the head.

My pump has std 7/8" sections for all 3 stages. Peterson pumps gerotor type so sizing of sections may not be comparable to the make and model of pump you are using.

 

For the pressure section:

Ultimately what you need to do is match (slightly exceed) the pressue & flow demands of the engine.

The std S2000 internal oil pump is rated at 58.4 litres/min at 6000 rpm and the relieve is set at 85 psi.

At the 9000 rpm red line, the flow works out to 87.6 litres/min or 23.1 usgpm.

Obviously you want enought oil flow to make sure you don't loose oil pressure. Assuming Honda sized their pump correctly, matching the flow should be fine. Providing significantly more flow is just waisting hp and creating extra heat in the oil as it is relieved over the bypass.

The flow of my pumps pressure section is 16.3 usgpm at 3000 rpm and has a 5000 rpm limit.

I ended up with a drive ratio of 2:1 so my max pump speed will be 4500 rpm and flow will be 24.5 usgpm.

All of this sizing was discussed and approved by a tech from Peterson. They said this should be fine for a relatively stock motor with the stock red line.

I am using a single AN-12 line to connect the outlet of the pump to the engine which matches what you are doing.

The pumps internal relief is internally piped to the scavenge return to tank port. Your AN-10 should be fine as long as the pump is not grossly oversized.

The standard size fitting on my pump and tank for the line feeding the pressure pump was also an AN-12. From my industrial hydraulics experience I felt this was too small and thought going up to an AN-16 line will only help insure the pump doesn't cavitate.

 

For the scavenge section:

I guess this all comes down to how much vacuum you want to draw. The theory is that more vacuum = more hp. I wasn't too concerned with this and was more concerned with very limited space for the pump, lines, etc so I only went for 2 scavenge sections. Peterson recommended that as long as I had 2 scavenge sections that were the same size as the pressure section, I should be fine. This of course is totally dependant on getting the scavenge pickups in the pan in the right spot that they are sucking oil and not just air.

For line size, I am going with 2 AN-12 hoses to the pan, 1 for each section.

For the return to tank I am running a single AN-16 line. My pump has the option of internally manifolding the outlets together, so I am doing this to keep the number of lines down.

I would recommend using 1 AN-12 hose per section for both the inlet and outlet. You can manifold the return to tank lines and run 1 line. This line should be at least one size up from the pressure out line size.

You should consider running scavenge filters in the lines from the pan to the pump just to protect the pump.

 

The Tank:

You tank size should be OK. I doubt you will be able to run 7.5 quarts in it. I'm guessing that is its total internal volume. You can only partially fill these tanks as you have to keep the oil away from the inlet and breather. I don't know how much you'd actually be able to run in your tank but likely something like 2/3 full.

My tank is slightly larger, being 7" diameter x 16 1/2" tall.

Again in sizing a tank to fit in a 7, size is always going to be a limitation unless you are going to totally sacrifice the passenger compartment or something.

Large is better, but I figure anything that is somewhat larger then the stock oil pan capacity should be fine.

The tank I am using has a built in breather tank and filter so this made dealing with this easy.

In your case, I would comment that your tank vent size is very small. To try and keep the oil in

[RDROCKT]

Jack,

Received the drawings and thank you. Thanksgiving travel has slowed my response.

 

I agree with all of your comments and sizing. I must say that my research has shown that there is no such thing as too large a tank unless one is concerned with space and weight! That having been said, there is always a practical limit and I am now planning to install the largest tank I can find that will fit.

 

My pump has male AN-12 fittings on all openings so I have simply used AN-12 lines everywhere. Your idea to open the supply line up to an AN-16 has me perplexed. If you have an AN-12 opening in the tank and pump, how will placing a section of AN-16 hose in the middle help you?

 

Re the return line; my pump has the scavenge stages internally linked and bypassed to a single port, eliminating the need for an external manifold, but here again the outlet fitting is an AN-12.

 

I agree with your statement about the vent line and this will be upsized forthwith and routed per your instructions.

 

I still find it hard to believe the flow that the S2000 engine requires. ~23-25 gallons per minute! That means that if you have an eight quart system, the whole thing cycles every 20 seconds! It kind of boggles the mind and leads me to believe that the volume and cooling are critical. (duh)

 

What are you planning to do to introduce the pressure line to the block? I would imagine a sandwich plate would be easiest but have not found one with large passages yet. Using the stock cooler will be a plus.

 

More as it occurs,

 

 

[Birkin42]

Hi Chuck,

 

I had Peterson put a AN-16 fitting on the tank for both the inlet (scavenge return line) and outlet (feed to pump). I believe the -16 inlet was the stock size but the outlet is normally -12.

Peterson offers a number of different size fittings for their pumps so I went with -16 for the pressure stage inlet, -12 for the 2 scavenge stage inlets, -12 for the pressure stage outlet, and a single -16 for the combined scavenge section outlet. My pump is internally manifolded like yours but has a block off plate for the 2nd scavenge stage so it has provisions for separate return lines.

Going to the -16 lines for the pump in and scavenge out may be overkill, but given the pump flow, I wanted to play it save.

Now I'm dealing with trying to get a lot of large hoses into a very cramped area.

 

I am in the process of trying to determine what I want to do with oil cooling. I have waffled all over the map on this but am currently leaning towards an external air/oil cooler mounted in front of the rad with a thermostat to control the temperature. I think you could run this with or without the stock coolant/oil cooler. I think I'm going to try an figure out how to do this so that I can go either way without significant harware changes. I was thinking of a Mocal Laminova coolant/oil cooler but am concerned about the capacity of the coolant system, the pressure drop on the oil side and packaging issues.

 

To connect the pump pressure feed to the motor, I had a few thoughts.

First you need to decide if you want to bring it in through the pan to the port in the block where the stock oil pump connects. Going this route solves a lot of problems around the stock cooler/filter, but I believe I won't do this as it complicates the custom oil pan further and adds another oil line connecting to the pan prone.

If you are not going to use the stock cooler/filter, the easiest thing is to make/buy a blocking plate to seal off the annular ring and provide a fitting to the center pressure port. I think you can buy all the stuff you need for this from Mocal and possibly others. You will need to block off the outlet port. If you want to make it yourself the female thread in the block is M22x1.5 and the thread for the stock oil filter is M20x1.5.

If you want to keep the stock oil cooler and filter, I would recommend a sandwich plate from Canton/Accusump (not sure if it has a big enough port) that provides a single port to the annular ring and with this you will need to block off the feed hole coming up the block from the stock oil pump. If you want to keep the stock oil cooler but not the filter, you could either use the same Canton/Accusump sandwich plate and with this use a remote filter blocking plate in place of the filter. You will need to pipe the inlet/outlet together. The other option is to buy just the remote filter blocking plate, plug the pressure feed port (center) and connect your pump feed to the annular ring connector. With this arrangement, you are now pumping the oil backwards through the stock cooler. To get the oil into the pressure port in the engine, take the stock fitting that goes through the stock cooler and drill some holes through this and turn a portion of the threads down. I can send you a sketch of this. I did the math on this and it should not present a flow restriction. The last thing you will need to do is block the oil feed hole coming up the block from the stock oil pump. Kind of sounds complicated but I don't think it's too bad. There may be a way you can drill a passage in the engine block to solve this, but personally I'd prefer not to modify the engine block in a way that is not reversable.

 

As you can probably determine I am still trying to sort the system out. Any thoughts you'd have on this would be welcome.

 

[blami]

Sorry to enter this thread at such a late date but after noticing that Bob has a Caterham with the Vauxhall engine I had to ask: have you considered the Caterham dry sump system? Caterham's system is unique in the sense that the oil tank is built into the bellhousing unit, so tank placement or accessibility is not at issue.

 

I was planning on using the Caterham dry sump system on my car (in fact, I purchased the system) but I did not like how the external oil pump, mounted on the right side of the engine (and below the alternator) required that it's drive belt be routed so close to the alternator drive belt. A broken alternator belt would likely take out the oil pump belt.

 

This would not be an issue on right hand drive cars where the alternator is mounted on the left side of the engine.

 

Modifications to the Caterham drysump system could probably be made that would lessen my concerns but I never got around to attempting them.

 

I have found that the Vauxhall engine, with Caterham wet sump, windage tray, and "fuel-cell" foam in the wet sump actually has worked well for me---no oil starvation problems after 17,000 or so track miles. However oil temps were another issue, but resolved with the addition of a Mocal oil cooler.

 

Yes, my Vauxhall is Swindon tuned too--218 HP on Weber 45 DCOE carbs.

 

Good luck with your project.

 

Bart Lami, 1993 Caterham HPC

[bsimon]

Bart,

 

I looked at using the Caterham system as well. There were just enough issues with that system that I decided to go with the Pace system.

 

The Caterham bell tank tends to blow the hydraulic seal for the integrated throwout bearing. Heat from the clutch tends to french fry the seal. De-aeration is a concern since I believe the swirl section of the bell tank is a bit small in diameter to be effective. I have a bit of concern about total oil volume as well. Of course this is just my opinion. I'm sure there are a lot of CC dry sump systems out there that are working just fine.

 

I must admit there is a bit of security with the Caterham system as the pressure pump is internal. If you throw a scavenge belt, you'd still have OP until the tank is drained. With an external pressure section, if the belt parts, so does the OP...instantaneously!

 

One of the chaps on BC built a nice enclosure for the oil pump drive belt to protect it from whatever perils it might encounter. He plans to manufacture them for cheese motors. Unfortunately he has no plans for VXs or Zetecs. I'm thinking fabing something along the same lines for my car.

 

My chassis is right hand drive with the alternator on the victim's side of the engine. The hard part of fitting either the CC system or the Pace system is working around the steering shaft and under the intakes.

 

I'm currently running sump foam and the CC cast sump as you are. During some parking lot skid pad "experiments" I did see some dips in the OP after extended right hand turning. I added a 2 quart accumulator (Accusump) for peace of mind.

 

I guess there aren't many of us Vauxhall guys in the States. I've only met 2 in person and chatted with one from Canada and one from California via e-mail.

[blami]

Hi Bob,

 

Sounds like you have researched this throughly. Let us know what you think of the Pace unit once you have it sorted out.

 

I have also read about the hydraulic seal for the throwout bearing being a problem area for Caterham. I was told that this was not an issue with later bellhousings but to be honest I don't remember how the issue was supposed to have been corrected. Maybe wishful thinking.

 

You're right about there not being many 2.0 Vauxhalls in the States. I know of a couple in Ohio. It would probably be a good idea to try to collect the names and locations of owners of Vauxhall powered Sevens in the USA--we could then compare notes, sources for parts, modifications, etc.

 

What do you think?

 

Bart

 

 

[Sean]

Dry sump tank source link time:

 

http://www.petersonfluidsys.com/

 

http://www.mocalinc.com/

 

http://www.pegasusautoracing.com/

[RDROCKT]

You might want to try this link for MOCAL in the US

 

http://www.batinc.net/mocal.htm