Performance Boats Forum banner

1 - 20 of 45 Posts

·
mo balls than $cents$
Joined
·
11,734 Posts
Discussion Starter #1
we took out my uncle's blown injected 547 tx-20 yesterday and we're still having injection issues. i think it doesn't have enough fuel supply volume, he used smaller lines than recommended in the enderle instructions he got from good vibrations. it's a bitch to start, you've gotta prime the shit outta it, then once it's cranked up, you gotta stay popping the primer to keep it runnin till it begins the surge. once it's surging, it does fine till we hit wot, then it'd hook ass for 3seconds, go lean and die. i think it just doesn't have big enough fuel supply lines and the high speed bypass is returnin more than the small supply lines can keep up with.

what line sizes should the tank to 80a and 80a to meter block be? he's got 1/2 tank to pump line on it now, and the line from the pump to the meter block is even smaller. i think this is the issue but needed some other opinions. he had all stainless made up and i'm trying to get him to go get some cheap bigger 1's made up today to see if it solves the fuel starvation issue at wot.

appreciate any help fellas, i'm no mechanical injection guru, just learning the stuff myself and havig fun with it:)devil
 

·
Registered
Joined
·
4,677 Posts
tom i hate that hope you and billy get it figured out,that mill sure sounds good.i remember it from the shovelnose:)hand
 

·
mo balls than $cents$
Joined
·
11,734 Posts
Discussion Starter #3
tom i hate that hope you and billy get it figured out,that mill sure sounds good.i remember it from the shovelnose:)hand
that's the prob, it did this in the shovelnose too, and he using the same lines he had in it;) i looked up the line size and it's supposed to be 3/4 i.d., no less. i called and told him to go get a hyd 3/4 i.d. line made up and we'd run the boat again saturday. bet it cures it.
 

·
mo balls than $cents$
Joined
·
11,734 Posts
Discussion Starter #6
;)
Hey Tom,Hows your beast running u happy with it
YES, I'M HAPPY:D:)devil new loader should put me where i wanted to be on motor, i added shoe depth to it last nite. i was runnin over the top of my hp range and needed to feed the pump more water. removing 100lbs worth of blown stuff will sure change a boat's attitude:D;)
 

·
Registered
Joined
·
4,677 Posts
yeah i remember it cutting out some when he was on it a bb:|errthats gotta piss you off.i remember looking at a setup at scotts here not long ago.i asked why the lines were so big and he blown injected:Dthose were some big ass lines my friend,lol!!!the fuel log he made was even bigger.you fellas will cure it with bigger lines i bet;)good luck
 

·
mo balls than $cents$
Joined
·
11,734 Posts
Discussion Starter #8
Hey Tom,Hows your beast running u happy with it
yeah i remember it cutting out some when he was on it a bb:|errthats gotta piss you off.i remember looking at a setup at scotts here not long ago.i asked why the lines were so big and he blown injected:Dthose were some big ass lines my friend,lol!!!the fuel log he made was even bigger.you fellas will cure it with bigger lines i bet;)good luck
he was wanting to get some 1250's and just carb it, but i talked him out of that and we'd put our heads together on it and get r done. we'll see saturday if its fixed, cause i don't want him having any excuses when i saw his ass off:D:)devil
 

·
Registered
Joined
·
4,677 Posts
he was wanting to get some 1250's and just carb it, but i talked him out of that and we'd put our heads together on it and get r done. we'll see saturday if its fixed, cause i don't want him having any excuses when i saw his ass off:D:)devil
hil:)he wont like that,funny how no one has given any advice:)Unsure
maybe someone will help ya:D

you think you can take him:)bulb
 

·
mo balls than $cents$
Joined
·
11,734 Posts
Discussion Starter #10
hil:)he wont like that,funny how no one has given any advice:)Unsure
maybe someone will help ya:D

you think you can take him:)bulb
there's not alot of mechanical injection gurus around during the day;) my homey fiat already pm'd everything i could wanna know, he's helped me wrap my mind around this stuff and i think i've got a pretty damn good handle on mechanicl injection now, its alot more simple than tuning a dominator, and that's the truth.

won't know till we're both runnin 100% and both have some good gas to run. he'll get nitrous too if i do:p
 

·
Registered
Joined
·
2,034 Posts
Did you get the issues straightened out?
-12 from tank to pump inlet
-10 to barrel valve
Gas or alcohol?
Wags
Tank height can make starting hard also. These pumps don't suck all that well. If the tank is pump height, an engine will usually run on the pump as soon as it fires. If the tank is on the floor or in a tunnel, it will take more priming.
 

·
Registered
Joined
·
3,869 Posts
we took out my uncle's blown injected 547 tx-20 yesterday and we're still having injection issues. i think it doesn't have enough fuel supply volume, he used smaller lines than recommended in the enderle instructions he got from good vibrations. it's a bitch to start, you've gotta prime the shit outta it, then once it's cranked up, you gotta stay popping the primer to keep it runnin till it begins the surge. once it's surging, it does fine till we hit wot, then it'd hook ass for 3seconds, go lean and die. i think it just doesn't have big enough fuel supply lines and the high speed bypass is returnin more than the small supply lines can keep up with.

what line sizes should the tank to 80a and 80a to meter block be? he's got 1/2 tank to pump line on it now, and the line from the pump to the meter block is even smaller. i think this is the issue but needed some other opinions. he had all stainless made up and i'm trying to get him to go get some cheap bigger 1's made up today to see if it solves the fuel starvation issue at wot.

appreciate any help fellas, i'm no mechanical injection guru, just learning the stuff myself and havig fun with it:)devil
Thats a simple one you are starving the motor and roasting the pump!!! get a real supply line and call me in the morning,It needs a big supply line just like it needs bypasses. M
 

·
Registered
Joined
·
3,869 Posts
Thats a simple one you are starving the motor and roasting the pump!!! get a real supply line and call me in the morning,It needs a big supply line just like it needs bypasses. M
Here comes the add on!!! that big a motor would require atleast a #12 inlet and #8 for the feeds and bypasses to the tank. M
 

·
mo balls than $cents$
Joined
·
11,734 Posts
Discussion Starter #14
we've gotten 3/4 line on the tank to pump now and 1/2 to the hat. we used 6an on the high speed bypass and idle bypass back to the tank at least 2 1/2 ft away from the supply bung on the bottom rear. we used a loop line on the shutoff valve bypass and its returning to the pump inlet.


so does this look alil better???????? gonna try it out tommorrow
 

·
Registered
Joined
·
2,034 Posts
That may work...1/2 is only a -8. On gas it will probably work. On alcohol it will be small.
If still having issues...plug the high speed to take something out of the equation.
Is it a square barrel valve or the "K" valve?
Wags
 

·
mo balls than $cents$
Joined
·
11,734 Posts
Discussion Starter #16
That will be fine.
If still having issues...plug the high speed to take something out of the equation.
Is it a square barrel valve or the "K" valve?
Wags
square.

so plugging the high speed would make the pressure stay high right? won't that hurt the pump?
 

·
Just another Wannabe
Joined
·
1,199 Posts
No. Some gurus really put a ton of pressure to these systems. If it is set up Jim Maher style, (good vibration motorsports) it is running very low PSI compared to some of the others. The pump has lots of room. We have run without high speeds on many occasions to eliminate one variable from the deal. The thing will run just fine but be a touch fat on the top end. Sounds like something this deal could use. If it is an alcohol engine, a little fat won't hurt anything, and the performance change from having a properly working high speed is very minimal.
And since it is square, please read the number on the end of the barrel valve ramp. (Where the butterfly shaft meets the barrel valve. On the end of the barrel valve spool.)
Right here;

That is the brains of the injection. And thinking about it now, it almost sounds like you have the wrong one in the barrel valve.
 

·
mo balls than $cents$
Joined
·
11,734 Posts
Discussion Starter #18
No. Some gurus really put a ton of pressure to these systems. If it is set up Jim Maher style, (good vibration motorsports) it is running very low PSI compared to some of the others. The pump has lots of room. We have run without high speeds on many occasions to eliminate one variable from the deal. The thing will run just fine but be a touch fat on the top end. Sounds like something this deal could use. If it is an alcohol engine, a little fat won't hurt anything, and the performance change from having a properly working high speed is very minimal.
And since it is square, please read the number on the end of the barrel valve ramp. (Where the butterfly shaft meets the barrel valve. On the end of the barrel valve spool.)
Right here;

That is the brains of the injection. And thinking about it now, it almost sounds like you have the wrong one in the barrel valve.
i'm alil slow at this so please be patient with me:D what may be the "wrong one" in the barrel valve. keep in mind i'm still a fresh newbie to this mechanicl injection stuff. appreciate the help you guys are giving up though, thanx guys:)devil
 

·
mo balls than $cents$
Joined
·
11,734 Posts
Discussion Starter #19
so he can run without the high speed bypass on a race gas set-up? that would damn sure boost fuel volume. we've corrected the fuel supply line size issue and are gonna take it out tommorrow for another test run. current pill is a 112 in the h.s. bypass, should this be a close starting point?
 

·
Just another Wannabe
Joined
·
1,199 Posts
There are several "ramps" or "spools" for that square barrel valve. They are replaceable units in the square aluminum unit. It does the metering of the fuel. There is one for a tunnel ram MFI that shuts the fuel completely off to the front return pad when under more than part throttle. There is nitro ramp that goes 100% fuel flow right off of idel, and a few others for gas, alcohol, etc. Having the wrong one in can create quite a headache. We really need to see that number to see which one you have.
And taking the high speed off on a gas engine does not have the leeway as an alcohol engine. Alcohol can go pretty darn fat without losing too much power. Gas, - well - Not so much.
 
1 - 20 of 45 Posts
Top