pstorti

I think its closer to 70K but what setup is less than half that? I like the Xpower because it is light and eliminates the need for a transmission, less space needed in the motor room, more space for the boat. Arnesons are great in the right application, but I would need the dropbox style which are not as bulletproof as the straight ones. There are very few options that can reliably handle 1250+ ftlbs at 2000 rpm, but I am open to suggestions.

pstorti

Joe here is a close up of the supply and return lines to the engine


Same view but zoomed out the painted grey line leaving the back of the filter housing is the return to the cooler


This is the FASS lift pump, the blue elbow is from the tank, the line above it goes to the engines (split by a Y), and the line at the back of the housing is the return to the tank, first removes dirt and water, then removes any air and pressurizes the fuel.




The plunger pin from inside the aneroid on top of the pump, do you know if there are different versions of these that would fit the pump and make it deliver more fuel?




This orange boot is the turbo outlet tube to the aftercooler

kidturbo

After discussing my particular EGT temps with several members and diesel tuners, I'm diffidently hitting exhaust side limitations on the turbo. The overall performance is excellent, everywhere but WOT under a heavily fueled tune. It's manageable without the water injection by just selecting a lower hp tune setting, which equals sacrificing about 5mph on top end. There is one size larger A/R housing I'd love to try before looking at bigger turbos. I've also considered shaving the wheel, or adding a waste gate, just need a good turbo guy to pitch in.

Also found that the high RPM coolant temp issue I was experiencing is mostly related to running an open loop cooling system. I recently swapped out 160 thermostats for 190's and lowered the seawater bypass pressure to help build some engine heat and increase normal operating temps to around 180F from 160F. While this greatly helped fuel economy, at WOT it's bypassing too much water and the temps creep up...

Lots of give and take when cranking up these modern diesels far above factory specs in marine use. But what other engine platform can you unlock 150-200 hp without even turning a wrench, using nothing but a laptop...

--
pstorti

are you feeding both engines with that single FASS ?

7075T6

There is a certain feeling with aluminium... but an Outerlimits SL 44-hull would do the job...
2xengines/trans/drives about 4400 lbs.

HabanaJoe

I see said the blind man, but we're kind of hijacking this thread and it's really about that beautiful hunk of aluminium! Our discussions have to do with diesels as well and more performance so I apologize for what we're doing but I think it fits in the general catagory of beating the crap out of gas boats in the long run!!!!

A few observations and concepts:

1) The Yanmars have fuel coolers on them not because in a boat like yours you need them, the Yanmars are designed to fit "general" marine applications and many, many cruisier or inboard boats have fuel tanks in the engine room. So the engine heat will help heat the fuel and in time that needs to be cooled off - hence the fuel coolers on your engines. Your tanks I'm guessing are forward of the engines, separated from the engine bay and lieing in the bilge right next to the water keeping the fuel cooler than outside air temp.

2) that FASS pump is the nuts, very cool idea but I see a problem. It's a gear style pump I think(maybe) judging where the motor is mounted, so the FASS pump can pump lots of GPM, you have the pressure cut down and therefore return most of the fuel right to the tank, I'll add heated fuel. A couple degrees adds up over time because if the Delta is 3 degrees as the whole fuel tank rises each cycle of the tank continues to raise by 3 deg until you reach whatever the max is.

3) your Yanmar fuel filter assembly has the return built into it to de-airate the fuel that is why there is a return there. The fact that the return goes through the fuel cooler says to me that your engines uses less than 10% of the fuel delivered to the fuel filter housing the rest is bypassed right back tot he tank and is cooled. That filter hosuing has a mechanism in it to restrict fuel pressure to the fuel injection pump whether it is a spring and ball or a restrictive passage but something says "hey the engine won't use all this fuel and we need to send some back to the tank"

4) I think first you need to have the fuel bypass from the FASS going through your feul cooler, I know in #1 I said the cooler is there for other applications but if there USE IT, the fuel returned from your engine is sooo small it could heat a think. The bulk of your return fuel is from your FASS pump and your filter housing, more from the FASS. Gear pumps under pressure will make heat so I think whatever advantage the cooler is giving you, you are negating it with the FASS pump - plump it through the coolers. YES your engine fuel consumption monitoring will be way off but what's the goal better performance or MPG?

5) to increase pressure to your fuel pump you need to bypass less from the filter housing, you can jack up the FASS pump untill it flows more fuel than the filter head can return which I think you are at that point because like you said "the primer is so hard you can't push it down" but you really need to look at where the pressure drop is? The fuel gauge on the FASS pump does tell you much you need to measure pressure on the line between the fuel filter housing and the fuel pump itself that is the pressure you need to raise.

6) the aneroid controls the amount of fuel delivered during acceleration, once you reach enough boost pressure the aneroid is rendered useless, it does nothing. The aneroid is a pollution control device so you don't make BIG smoke clouds trying to get on plane nothing more than that. What your showing me in that one picture looks like the plunger has a helix cut in it,a spiral curve - does it or is it just the angle?

I'm guessing that plunger where it is threaded on the top goes through some type of diaphram and boost either raise or lowers it- correct? The taper again I'm guessing is what allows the amount of fuel to pass around, the smaller the dia the more fuel the larger dia the less fuel, I don't know that type so I'm guessing but that is what it looks like.

You need to understand when I worked on verisons of things like that it was a simple spring and diaphram connected to a rod that simpley did not let the fuel rack advance because the rack was on a yield link - LOL

Old DDA reference non turbo engines had a solid link bar between governor and "the rack", when they tried to first put some soke limiting on turbo DDA's the solid link bar became a spring loaded bar simpley to allow time for the turbo to spool up - basic yet worked OK.

stirling

Do you diesel guys think I,m going to need lift pumps on my 440 yanmar diesels ? I plumbed the fuel lines from the fuel tank to the filter all in # 10AN and from the filter to the mechanical injection pump its #8AN .
I was/am under the inpression that the mechanical injection pump pulls enought fuel ...

HabanaJoe

I would think you want your water temps to be closer to 200deg? You said lowered the seawater bypass pressure, you mean water is going through the engine faster or slower now? If you are running an open loop meaning seawater in and back out how are you controling air in the engine?

My guess is and I could be dead wrong that water is going through the egine too fast, you are not taking out enough heat and the high temps you see might be steam pockets, again i don't know what you're cooling looks like.

We had similar problems years ago and had to add various vent lines at all the high spots to get air out of the block, remember your cylinder temps are very high, cyl head temps are boiling hot because of your EGT's (that heat is cooking those heads and goes into the water) and the high compression with the turbo makes for cavitation around your cylinders whether there and liners or not the water will still boil around the cylinders from the oscillation that is just a by-product you can't get away from.

Just think about these things sometimes what you're seeing is the result of other forces and that what it appears to be on the surface?

HabanaJoe

stirling - the fuel injections pumps do not pull any fuel at all, they are a pressurized storage area where fuel is collected before it is forced into the high pressure plunger. All inline plunger and barrel or rotary pumps have lift pumps when you look at a DB-2 (on old 6.9, 7.3 & 5.7) there are actually 3 fuel pumps, supply or lift (externally mounted) suppling a medium pressure vane pump in the DB-2 to supply presure to the rotary plungers for high pressure.

7075T6

[ATTACH=CONFIG]515469[/ATTACH]
Updated exhaustmanifold with new vent.

pstorti

Yes that one pump is overkill for the amount of fuel my engines need, but they make the same model capable of flowing up to 260GPH so unless you are putting them on a pair of 2000hp MTU's don't know why you would need more than one, I also tested it with the FASS off and the motors can still pull fuel through it, in case it died, I also changed some of the wiring to marine grade components as the FASS stuff is not made to keep out the salt, I coated the hell out of it with Corrosion X and it still looks brand new. I think it helped my MPG marginally (.1mpg) but it did help a lot with acceleration and 2 mph on top end I was impressed. I would love to have a pair of your engines in my boat the thing would fly!