tajabaho1

I used to use premix alot.......but ever since the turbo install, I haven't

always used idemitsu though, seems to be working fine with the stock fuel pump

this one just seems unable to feed enough fuel to my car while under load

rising fuel pressure regulator fails

swoope

iTrader: (5)

in retrospect,

dumping it in first might not be the best idea.

but then again i did try lots of different types with my first pump..

i think the dumping first with unknown stuff might have been residual failure in my second pump.. clean the sock, it got better.

the wiping of the bottom of the gas tank was a clue.. both sides.

hence the new method of premixing..

that is just my opinion, i could be wrong.

btw, i am doing 5oz idemitsu ~3oz of fp+. i always over pour it.

beers

StealthTL

iTrader: (1)

I put two gallons of gas in, then dump the premix bottle, that way if there is a problem with the fill, I'm not running on 50/50 gas to oil! (happens....)

I mix real heavy, 500ml to a 50 liter fill, so 100:1, and since I started, half the bottle has been Lucas UCL - I love that stuff! People have commented that they see grey smoke when I change gear in spirited driving.....

The balance is synthetic ISO EG-D grade two-stroke of various brands.

S

swoope

iTrader: (5)

yep,

but you added smarter. and likely less experimental.

confessions come soon.

beers

mysql

When I refill, there's usually 3-5 gallons of fuel still in the bottom of the tank. So it's not like the gas tank is dry. Even so, I've mixed the premix with gas, and it combines quite well. So I don't know how the clog theory goes.

BTW, I had to drive to work today with the RX-8. The car ran perfectly normal. If it's a clog, it clearly fixes itself after cooling down.

dillsrotary

Though i'm not as knowledgable as others in this thread, i've had your exact same symptoms on an old car, turns out the fuel pump was over heating.

mdw1000

I've had the left turn fuel starvation issue with over a 1/4 tank at the track on the stock fuel pump. I wish this wasn't the case because the reduced weight would be nice. Plus not having to put gas in it two or three times during a track day

Did you do anything to prevent the issue, or did your car just never have it?

olddragger

iTrader: (3)

Ga guys been dealing with this issue about 2 yrs now.
No one has ever found out exactly what is the cause of the fuel starvation we experience. Speedsource can fix the tank for a fee and it aint cheap.
But if you are concerned over the weight of 4 gallons of gas then i guess you are ready to pay the price.
After disecting several pumps and using only deductive reasoning the best we can come up with is the sediment in the gas(we all have that some more than others) plus pre mix, plus the very small sump area that surrounds the pump all contribute to pump failure on the track. If you keep the tank at 1/2 full it allows the gas in the twin tanks to constantly wash the sediment out of the small sump area in a better way. it also provides adequete amount of gas in the tank when adding the pre mix as most will not go through the inconveinnce of pre mixing the premix.
Our pump has a high flow rate, the harness is good IF it is connected properly . I feel strongly that this is a filter problem. a friend ran flow tests on a symptomatic pump (one of mine) and a new pump and the flow rates were down over 20%. Attributed to the filter. whether 20% flow decrease can have that affect on out cars--i dont know. The pump itself was fine.
I do know when we place a new unit in the car the symptoms go away. i do know that since I have been keeping my tank at 1/2 or more at all times--i have not had a problem. Take it for what it is worth.
On the 2 pump ingenious system ole Dan did--that was great--just be careful of the safety issues (fuel cut off on turn over etc) involved.
olddragger

MazdaManiac

iTrader: (3)

Just never had it.

I did have a pump resistor pack that would overheat on long-ish trips, causing the pump to not switch up into high speed after being on the highway for an hour or more.

Outkast187

Theres no real need in mixing the oil/gas before pouring in(wont hurt anything though). Its been tested to death, and the current oils mix very well without mixing them manually. This is coming from Bel-Ray, Klotz, and MAxima themselves.

GrRx8MaZdA

damn i havent installed it yet-have it sitting in my room-and havent premixed from the day i bought the car but i m really starting to worry if this is going to fail in my turbo kit...

Scott???Any possible upgrade to fix the problem everyone seem to have???You know i cant have my car to your shop so an upgrade solution would be prefferable

tajabaho1

mysql, did you take off the pump yet?

what I've noticed is that I would lose pressure underboost only when my car has a quarter of a tank of gas left, I filled it up today and the problem has gone away, the pressure rises (64-65psi) under boost now

hopefully it goes away forever

mysql

The issue was so bad last weekend that I was on a slight incline and I wasn't able to move up the hill. The car was stalling unless I reved it above 1,000 rpm, and if I gave it any load to go up the hill, the engine would stall and die on me. I ended up waving people to go by me, put the car into reverse, and went backwards with the rear of the car going into the oncoming traffic lane, then was able to pull off the road where there were some shops (Where I had a nice hamburger at 5 Guys).

So long story short, the pump issue gradually surfaces, and if you do not stop driving immediately, it will gradually get worse till the car is unable to move. I would guestimate there is about a 5-10 minute window from the problem appearing till it's so bad the vehicle is unusable.

All of this happened without any boost, and with a full tank of gas.

I don't expect to have any work done on the pump till this weekend.

GrRx8MaZdA

Ok thats very serious mysql...There must be an upgrade soon enough...Sorry to hear

mysql

So you want an upgrade for the upgrade? lol


Let's see if Scott wants the pump back or not. When I get it off, I can snap photos to share.

GrRx8MaZdA

If something i have bought is not good i want a version which will solver the problems..Cause right now it seems everyone with this pump runs the same problem

rx8 man

iTrader: (1)

Haven't had my pump out, and not knowing what the set up really was like, I went hunting in the maunal, so have post some pics from that maunal, most would have seen this, but as a ref....

olddragger

iTrader: (3)

for all that are interested check the "? interest for fix of fuel starvation issues" look at post 198 for the flow charts. thread has pics etc
olddragger

swoope

iTrader: (5)

correct,

not a complete clog, but one that does restrict the flow..

after a hour the pump overheats and does exactly what you describe in your post #96.

if you shut it off for about 5 or 10 min it will run just fine. i was confusing it as a coil issue. replaced the coils and problem was still there..

i also replaced the fuel pump resistor mention by mm. did not change a thing.

since the sock was cleaned all is running fine..

beers

mysql

that sounds logical, a combo of both sock clog and pump overheating mix.

from my viewpoint, regardless if the filter is changed, or the car sits overnight, the results are identical. I bet I don't have an issue with the pump for a few months before I see it again. It seems like I need to be driving it a good hour or so before I stand a chance of the problem surfacing. Like I said before, if the pump is clogging, that is worse news than if it was simply defective. One appears to be defective design, the other would be just defective.

Will try to get the pump out this weekend.

slavearm

To be honest I never had any issues with the pump in my two years or so.

mysql

heh. So that's 2 people in here with problems, one person without, and 2 PM's of people with problems.

Who else has one?

Jedi54

iTrader: (7)

^^^ whoa, those are not odds I would want in Vegas.

maxxdamigz

iTrader: (1)

I have a mazsport pump. No issue with the pump its self. I did have issue with the FPR immediately after installation. Mazsport warranteed the FPR even though I had purchased the fuel pump a year prior (it sat in the shipping box at the shop for a year). Pump has run fine for 4200 miles. I run very little premix 2 stroke and on some of my long trips (200 highway miles with basically no boost) none at all. My preference would to be to get my OMP modified for a slightly higher flow running off an external oil reservoir and not premix at all. Hopefully I can get that together before the spring.

mysql

You describe what I have in place Sohn adapter, with an external container. And accessport for higher OMP flow rates.

I still like premix though. It's all through the fuel instead of just at the edge of the seals. The 2008 and earlier cars have 2 nozzles and they are angled out towards the side seals, ignoring the center of the apex.