Squash Double Pumper Update - Significant Issues
 

Some of you may have seen my initial review of the Squash Double Pumper unit a few years back.
https://www.evolutionm.net/forums/ve...le-pumper.html

The systems was installed during the winter so my initial feedback was positive. However, once the outside temperatures rose several months later and started to exceed ~80F that is when the issues started to manifest. It started on a 4.5hr drive from Richmond, VA to Charlotte, NC when I noticed my fuel pressure starting to drop when driving down the highway. It got so bad the engine was starting to backfire from running lean so I had to pull the car over. Not knowing the cause I sat for several hours to allow the engine to cool and started trying to make it home. I eventually made it home, but 3-4hrs after my expected arrival.

I spoke with Squash and he felt the fuel was getting too hot so I spent a fair amount of money reconfiguring the fuel rail as well as changing my fuel filter setup. After no success I decided to pull the Double Pumper unit to see what was happening. I confirmed the fuel was getting hot because the fuel lines where extremely hot after use.

Long story short, it was determined the pumps where pressed against the bottom of fuel tank because the unit had been designed thinking the tank was 0.5" deeper. It turns out the mockup tank was somehow not accurate so all of the units where incorrectly designed. I wasn't upset because I appreciated that Squash was trying to support the community and I wanted to work with him to correct the design problem.

Fast forward to 2015 and I don't have the updated units that were promised to me starting towards the end of 2014. And after repeated calls, e-mails, facebook posts, and PM's, Squash Performance has decided they don't want to deal with the issue and even sent me a pissy response for raising my concerns on their facebook page.

Being an engineer I decided to try and resolve the issue on my own. I essentially needed to raise the pump at least 0.300" so I started by removing the double pumper assembly. As you can see below the pump is pressed against the bottom of the tank, which causes the pump to cavitate and heat the fuel. The other pump only runs when boost exceeds 12psi per my Haltech unit.

https://cimg6.ibsrv.net/gimg/www.evo...27b6585656.jpg

After the double pumper was removed you can see in the tank where the pump filters are smashed against the bottom.


https://cimg8.ibsrv.net/gimg/www.evo...27b6585656.jpg

In order to raise the pump I decided to order two additional gaskets, which are ~0.195" thick per gasket so two of them would raise the pump ~0.390".


https://cimg3.ibsrv.net/gimg/www.evo...27b6585656.jpg

Once you raise the pump the threads used to secure the housing are no longer accessible so I secured some M5x0.8 barrel nuts to engage the threads below the surface of the mounting flange.


https://cimg5.ibsrv.net/gimg/www.evo...27b6585656.jpg

The next step was to drill the holes in the double pumper to allow for the barrel bolts to pass through. The barrel bolts are ~0.275" OD so I drilled the holes ~0.300".


https://cimg6.ibsrv.net/gimg/www.evo...27b6585656.jpg

Finally, I installed the unit with the three OEM gaskets, which was a PIA. The final gasket is barely secured to the pump housing so you have to be careful that it doesn't pop off during install. After several attempts I was able to secure the unit with the additional gaskets. I had to add some washers because the barrel bolts where too long, but not that big of a deal.


https://cimg0.ibsrv.net/gimg/www.evo...27b6585656.jpg

I let the car run for a while with both pumps on and drove it around to allow the fuel to slosh with a full tank. The results thus far show no signs of leakage so we will see what happens. The real test is to let the tank run down below a quarter tank and see of the pressure starts to drop. It usually only takes 30min when the weather is warm and the tank is low for the pressure to drop. I will update the thread to see if this is a permanent fix.

I am disappointed that Squash chose to run and hide on this issue instead of working with me to resolve. I personally will never do business with Squash Performance again because of my experience. I also spent $24(barrel nuts) + $41(2x gaskets) + $5(washers).

Thank you for showing the problem as well as nice option to fix it. Very good, thorough information{thumbup.
Sorry to hear the company is not doing more to help out, this seemed like a very nice product.

I have tried to be more than fair with Squash Performance. The unit apparently has been redesigned to address the pump height issue as well as the further restricting of the supply side siphon to increase the primary pump capacity. Unfortunately, I was told in November of 2014 the new units were being anodized and would expect one soon, but that was more than 6 months ago and Squash Performance will no longer return my calls, e-mails, and PMs.

Mine has this issue as well. I spoke to Andy at Squash performance and he said I could send it in.
I figured I would just move the pumps up in the hangers and shorten the fuel lines, going off of my memory from when the pump was out.

240- Dies it look like the pumps can be raised in the hangers?

No, pumps have been raised as much as possible with the shortest possible hose. Additionally, if you look at the picture below you can see the area circled in red. This aluminum bracket secures the pumps and is fixed to the pump assembly. Therefore, even if you could shorten the hoses the pumps cannot slide up.

Apparently, the new design allows the pumps to move up, but only works with the Walbro 485's so the Walbro 400's are no longer an option. This is part of the problem because if you have Walbro 400's on your Squash Double Pumper then someone has to pay for the Walbro 485s that are required with the supposed new design.

https://cimg7.ibsrv.net/gimg/www.evo...27b6585656.jpg

OK.
I remember before I installed mine, there was more room than that. Your's definitely won't go any higher.

I have the 485s.

unfortunate that squash is treating you this way. one question - is the primary pump running full time at full voltage? if yes, that will cause fuel heating. and a comment - my walbro 400 (non-e85) lost capacity after less than one year of use. if yours overheated to the point of having no capacity at cruise, i'd say they are toast.

I cannot make sense of the situation so perhaps Squash can provide an update.


Yes, the primary pump runs full time at full voltage and has been for more than 2 years. I used to run the primary off the stock switched voltage setup, but because the siphon runs off the supply side I wanted to maximize the flow of the primary pump by running it hot wired.

Since modifying the Double Pumper to raise the pumps I have now run the tank down to empty twice and it has not lost pressure like it was prior to raising the pumps. At least up to now the pump appears to be operating with no issue. I can tell when the pressure is about to drop as the E85 gauge will slowly drop from 8-10% down to 1-2% due to a lack of flow.

I don't think the overheating of the fuel caused damage to the pump as the pumps just won't flow when the fuel temperature exceeds a certain amount. I'll continue to watch for signs of pump failure and report back if that happens.

I don't get it either, everytime I talk to them they are very helpful.

Perhaps they will tell you when the modified units will be available. I was promised a replacement unit once the new design was complete, but that clearly hasn't happened.

delete

What i dont understand is how a company makes a product and starts selling it without testing. Clearly they didnt test fit this product, or they would have seen its faults.
So fail.

Did you pull it out yet?

edit

The challenge with just removing and putting in something else is mods that had to be done to retrofit this unit. I had to cut the stock wiring harness since it was not PnP and I also had to switch to AN lines so you can't just easily swap back to stock without considerable time and expense.

My mod appears to have resolved the cavitation issue as I have not experienced a loss of pressure and the temps in Charlotte, NC have been 100F. While it did cost me ~$65 in parts it was simple to execute.

I got an inquiry regarding my comment on the siphon redesign so let me explain. The siphon is driven off the supply side, which eliminates the issue of overrunning the return line causing excessive fuel pressure at idle. However, you are taking away pump capacity because a portion of the fuel is being bypassed to run the siphon. I did some back of the envelope calculations with Squash and we estimated the amount of fuel bypassed was making my Walbro 400 flow like a Walbro 255. At my power level this was fine because the second Walbro 400 kicking on at 12psi was more than enough.

The redesign by Squash is supposedly to reduce the size of the siphon hole to decrease the amount of fuel bypassed, thereby increasing the primary pump capacity.

Since I have had great communication with Andy I wrote him and asked him to comment in this thread a few weeks ago. I am surprised he hasn't commented.....

Not sure if I can post here or not since we stopped our forum sponsorship, so if this doesn't make it through I'll know why.

Regarding the issues here - We discovered a few differences in the fuel tank depth that were not accounted for in the first design. Moving the pumps up higher was not a simple tweak to the design unfortunately.

The new updated units are finally shipping. We shortened up the unit to accommodate all tanks and generally updated the design. There is no longer any rubber hose anywhere. The pumps are sealed with o-rings. We have integrated the siphon functionality into our machined parts because moving the factory siphon over was, frankly, a PITA. We can also tune the performance of our new siphon however we want instead of re-purposing the factory one. The new design only accepts the Walbro E85 DCSS 450 LPH pumps. The new pumps also no longer have the 87psi bypass pressure. They go all the way to about 110psi.

For the people who had issues due to the pumps contacting the bottom of the tank, I apologize that the proper fix took so long to get done. Everyone who had this issue (that I know of) has already or will be receiving a replacement unit in the next week.

Did anyone receive their replacement unit? I didn't :confused:

Contact Andy.
I believe you will have to send your's to him and he will swap it and send it back.

Yours ships out today. You should see it Friday or Monday.

It depends on the situation - 240Z's setup was pretty well modified to try to get it to fit in the tank correctly. These pumps are very resilient but when we cut the barbs off and things like that to try to get them to fit it's best to just replace them.

I have gotten an updated pump but I have not had a chance to test it myself. English Racing installed it for me and as far as I know the install went fine. I'll update as I get time to test it.

Hi Squash,

I attempted to contact several times via message and email to no avail.
What is the best method to sort out the fix for this item from Australia, as I am having to run my setup with no pre-pump filters due to the bottoming out.

My email is: bjperry@gmail.com

Cheers
Ben

One week later and it still has not arrived.

I got so many promises about the date of shipping that it was rather absurd. In the end it did finally ship. So far so good but I'm not holding my breath until I get some actual time on it and make sure I don't have any issues.

I want to update everyone that I received the new Squash Double pumper with pumps on Monday. I haven't had time to install, but I will provide pictures and update the results of the newly designed unit.

I want to post an update regarding the new revised double pumper from Squash Performance. I have been very busy so I apologize for the delay installing the new unit. The quality of the new unit appears as good as the original. I placed both units on a rack so that I could have the mounting surfaces on the same plane.


https://cimg1.ibsrv.net/gimg/www.evo...27b6585656.jpg

I then took some measurements off the table to the bottom of the filters. You can clearly see in the picture that the new unit (on the right) sits between 0.25"-0.375" higher than the previous unit. I could not get an exact measurement because the filters on the old unit had been trimmed for more clearance.


https://cimg4.ibsrv.net/gimg/www.evo...27b6585656.jpg

I then installed the new revised double pumper. I could not get the unit to install without removing the EFI fitting for the crossover tube, but that took all of 2 minutes to remove and reinstall. The new unit is now installed and running.


https://cimg8.ibsrv.net/gimg/www.evo...27b6585656.jpg

Base fuel pressure did increase by ~1.5psi due to the larger pump. I also noticed that when I kick on the second pump (with a hotwire switch) the fuel pressure jumps considerably (~8psi) more than with the previous setup. I suspect this is due to the pumps being larger as well as the new revised siphon. I have the secondary pump kick on ~12psi so I am sure I will need to retune the car under boost.

The car is on empty so I will drive it around tomorrow in the heat to make sure there are no issues and report back.

UPDATE:

I ran the car ~30miles on an empty tank and did not experience any issue so I believe the revised units work as advertised. I did have to retune the car under boost because the fuel pumps are creating more pressure in the system, but after 5-6 passes I have it dialed in.

If the previous system was able to meet target fuel pressure, then I'd say that the new system is creating an overrun condition due to too much flow through either the FPR or the return system. If possible, you might want to run the return line from the FPR into a bucket/jug and see if you get the correct fuel pressure.

Base pressure before with one pump was ~45.5psi and now base pressure with one pump is ~47psi. With the previous setup when I would kick on the second pump at idle the base pressure would jump ~4psi and now with the new setup if I kick on the second pump at idle the fuel pressure jumps ~8psi. I am essential running a base pressure of 4psi greater than before when both pumps are operating.

If adjusting the FPR can't bring the base pressure below 47 psi, then its definitely overrun from some aspect of the return system. Or if its the stock FPR, then also definitely overrun.

Roger, that is not the issue. I run an adjustable Aeromotive FPR on the end of the fuel rail and I use the stock supply line as the return so essentially a -6. Also, because the siphon runs off the supply there is no restriction in the return line. I can run both pumps hot wired and still dial it to the desired FPR at idle. At least I could with the dual 400's, but haven't tried with the dual 485's.

I want to report that I have taken the new setup through multiple tanks of gas and have experienced no issues. I believe that the new design by Squash has resolved all the previously known issues.

Hmmm...great to hear.
Hopefully my replacement turns up one day.

Still no sign of my replacement hanger I was promised.

Looks like I have a ~$1500 paperweight. :(
At least it looks nice on the shelf.

They replaced mine and very quickly I might add.
Get in touch with Andy

Great Thread, brought the unit way back in 2013 and car has sat with this being one of a few issues we had at the time.
Have just emailed Andy and hopefully receive good news

Already heard back from Andy

Top Service that cannot be faulted

Thank you very Much Andy I really appreciate it

Just an update
have a good mate moving back from usa so getting andy to hopfully ship it to him before he has to pack his container.