Shhhhh.... Quiet Fairey

[Bassplayer]

Just fitted a Halyard silencer to the stbd engine (port tomorrow) started up both engines and wow what a difference! They claim 40% noise reduction and it is all of that. Most impressed. B*gger of a job, had to cut away a panel below the aft vanity unit and another below the aft heads. New panels needed to allow for the silencer. Glad I bought a cheap multi saw to cut the hose.

Soooo, tomorrow the port one - looks a whole lot easier.

Next week, lift and wash and new transducer for the plotter, then the lpg injection. Got the necessary to do this now.

Also managed to buy a very cheap Frigoboat a/c unit.

So a quiet, powerfull, economical, cool Fairey.

 

[Latestarter1]

Just fitted a Halyard silencer to the stbd engine (port tomorrow) started up both engines and wow what a difference! They claim 40% noise reduction and it is all of that. Most impressed. B*gger of a job, had to cut away a panel below the aft vanity unit and another below the aft heads. New panels needed to allow for the silencer. Glad I bought a cheap multi saw to cut the hose.

Soooo, tomorrow the port one - looks a whole lot easier.

Next week, lift and wash and new transducer for the plotter, then the lpg injection. Got the necessary to do this now.

Also managed to buy a very cheap Frigoboat a/c unit.

So a quiet, powerfull, economical, cool Fairey.

Good call, Halyard is real nice quality gear 3,000% better than Vetus stuff, doubt if you need to do exhaust back pressure check as you are using Halyard, you certainly would do if using Vetus!

Just spotted the LPG injection??

 

[burgundyben]

Mine has straight through 3.5 inch exhausts about 8 foot long, they make a racket and I love it!!

 

[Bassplayer]

Just spotted the LPG injection??

Just about to install. I have done the fuel cons tests pre wash off of bottom (the boat not mine) then will compare to the lpg figs.
If successful I will be offering this as a conversion commercially.
In case you didn't catch my earlier posts, this involves about 5-10% lpg injection into diesels with hopefully 30%+ improvement in power/economy.

 

[Latestarter1]

Just about to install. I have done the fuel cons tests pre wash off of bottom (the boat not mine) then will compare to the lpg figs.
If successful I will be offering this as a conversion commercially.
In case you didn't catch my earlier posts, this involves about 5-10% lpg injection into diesels with hopefully 30%+ improvement in power/economy.

No, passed on my blind side.

Nothing new, guys from Australia have been doing it for years.

I had oversight of project in 2002 with major UK distribution company. At the time emissions reduction was the key driver. Yes you will see big improvement in torque/power and smoke reduction. Cranfield had done a study of common rail diesel with sequential inlet port propane injection, resuts look encouraging and a paper has been published.

Yes, the large amount of excess air of turbocharged diesel engine has potential, even at rated rpm you are not stoichiometric, so extra power generated by LPG fumigation will give you a big positive boost.

Now the downsides power equals heat, do you know if cooling system can accomodate extra heat.....power equals heat.

Have you tested on a dyno? I was present when engine ran away on the dyno due to lack of fumigation control. Uncontrolled events DO occur, the results are terryfing.

At WOT the old Ford Dover/Dorset valve temperatures can get real marginal and unlikely that you have benefit of forged steel Sabre main bearing caps.

Finally, have you notified your insurance company?

My only advice with the benefit of experience of LPG fumigation is 'do not do it'. Initial results will be amazing, after that buget for replacing both engines.

Sorry to be so negative.........

 

[Latestarter1]

Bassplayer,

I took the trouble to read your earlier post.

Just remember one basic rule 'Propellers move boats, not the engines'.

As I have quoted before think of your engine control as akin to cruise control on a car. You set the revolutions, the governor on the fuel pump responds by producing sufficient fuelling to hold those revolutions and deliver the horsepower demand of the propeller. Take a look at your propeller law curve, there is only one place that the propeller is demanding maximum power that engine can provide, that is at rated speed, at anything below rated rpm propeller always demands less than engines potential power, adding greater potential across the rev range is pointless.

If you are correctly propped for rated rpm of 2,400 rpm (sounds like you have old Ford Dorset) more power with the same propeller will mean that your WOT speed has to stay the same. You will come up on the plane faster, however Fairey boats are not slow in this respect. To make use of the extra power you need to graunch on some more pitch, probably at least an inch.

LPG fumigation will produce large torque rise, Sabre learned real early that with the rpm constrained Ford motor pulling extra power/torque (anything over 250) the cast iron main bearing caps WILL fret, ultimately leading to spinning a main bearing, normally #5. Sabre fixed the issue by using their own design of forged steel main bearing caps and line boring the motor. This was 100% solution at even highest power output race motors.

Fairey boats do not respond well to extra weight, so far you have added mufflers, air-con, and now gas tanks........

Suggest that you do have serious conversation with your insurer and explain exactly what you are doing. Insurer may take the stance that installation needs to be checked out by qualified GasSafe technician. On the LPG program I worked on vehicles could only be serviced by fitter with Corgi registration! Insurance companies may not be aware of engine runaway risk with LPG fumigation, but you can be sure of one thing, if your vessel suddenly launches itself into another boat in the marina causing damage and or injury you will be on the rack.

 

[Bassplayer]

Hmmm...
Interesting.
OK, firstly, I am an experienced automotive and marine engineer of 40 years. I have installed a number of lpg conversions to cars.
LPG fumigation will increase power, but if you use the same power and speed as limited by the govenor and prop size, you will use less fuel as the burn is more complete. I am not aiming for more power as you rightly say the Ford Dorsets are limited to 2400 rpm and don't like loads of extra power being extracted. The idea is more complete combustion = less fuel used for the same revs/power.
There is no chance of runaway as there is an idle micro switch to cut off the lpg at the idle solenoid at tickover. There is an additional solenoid controlled by the alternator charge light. Another solenoid manually controlled at the dashboard in the wheel house and a manual valve by the tank, and a dry break connector at the tank, a gas alarm sensor in the locker which is connected to the main tank solenoid. So all bases are covered for safety. At a later date I will be mapping the gas using an ecu, which can be programmed to cut the gas if the engine over revs.
The insurance company have been told and are ok - provided it is checked out by and approved lpg fitter. I am already approved for car fitting, but would get an independant fitter to check it.
LPG fumigation is being used a lot in the commercial vehicle world with good results. i.e. minimum 30% fuel saving (governed engines again) and 80% particulate reduction.
Weight of silencers? About 10kg
A/C system about 20 kg.
Gas tank about 35kg
Not a lot, considering a full load of diesel is 1000kg!!
Or 2 fat persons 200kg
Or fill up the water tanks completely 100kg
Etc ad nauseam

I appreciate your comments - but I have thought this through. I will be happy to put my hand up if I am proved wrong!!!
Hopefully you will too!

 

[Assassin]

Would generally agree with Latesterter on this one, in addition considerable testing is underway on these systems and many similar gas injection systems on diesel engines, and their results are negative.

Problems from current testing have highlighted many issues, including:

Corrosion, damage, and removal of most standard diesel engine anti friction coatings.

Damage to chromium plated internal components such as piston rings.Damage to valve guides and valve stems.

Erosion of standard and composite head gaskets, only copper should be fitted.

Excess shock loadings to pistons, con rods, crankshafts, and all bearings due to the high volatility of LPG.

Massive heat rises in combustion temperature which are disproportionate to the power/engine revs.

Timing issues on older, more basic engines without electronically controlled engine management systems.

Excess wear on various rubber and rubber/plastic based components such as oil seals.

These are just some of the issues being found.

Three engine manufacturers have tried to develop engines to work with these systems, and getting them to work would increase the base price of the engine up by around 40-50% over the standard unit.

 

[vas]

Would generally agree with Latesterter on this one, in addition considerable testing is underway on these systems and many similar gas injection systems on diesel engines, and their results are negative.

Problems from current testing have highlighted many issues, including:

Corrosion, damage, and removal of most standard diesel engine anti friction coatings.

Damage to chromium plated internal components such as piston rings.Damage to valve guides and valve stems.

Erosion of standard and composite head gaskets, only copper should be fitted.

---

Excess wear on various rubber and rubber/plastic based components such as oil seals.

out of curiosity (and interest as I'm about to convert my petrol 2.0lt BMW car engine to LPG) do the abovementioned issues affect to some extent petrol engines as well?
Or is it the combination of diesel with LPG that is making the mess?
I know for example that the fitter on my car will add a small oil tank that will be pumping droplets of oil into the "lung" of the system (as they call it). Is it for the same reasons? Or high combustion pressures found on diesels compared to petrol engines magnify the effects?
Else a combo of 2X6lt engines with 1000lt of diesel tanks with a 200lt tank of LPG would give you a 50% + operation on the engines I'm sure I'd be interested and I'd not be alone!
Overcoming the psychological issue of hot e/r, two massive engines, and a big bomb-barrel somewhere in there...

cheers

V.

 

[Latestarter1]

I hoped that I was being a little more gentle than Assasin, however this is all fact.

Please consider this: Company set up in Wales to develop commercial LPG fumigation kit for vehicles about 15 years ago. Outfit was well recourced (Funding from Welsh Assembly Government) with two dyno beds and two potential major customers (Top ten UK hauliers).

For the reasons I set out and all the detail stuff set out by Assasin the whole properly funded project failed leaving the Welsh Assembly Government to pick up the pieces. I was the winner as I picked up some expensive AVL test cell equipment for next to nothing. You do not appear to have done any development testing or even have access to dyno for testing and yet still pressing ahead.

If we fast forward the 2012 London LEZ approved tester (Millbrook) of aftermarket systems has received no applications for heavy duty diesel LPG fumigation systems for LEZ worst case testing.

I hope I was polite im my response to your plan, however the concept of LPG fumigation has been explored and has proven to be a failure. 'If something looks too good to be true it generally is'.

Before Ulyden wades is I know that Watsila are developing medium speed (500 rpm) engines running on LPG to meet future marine emissions, however this is complex blue sky stuff, and Westport is talking to everybody! Yes I know LPG tankers are currently using a form of LPG fumigation to run medium speed main engines on the LPG boil off. However the LPG fumigation is causing all sorts of poppet valve and lubrication issues in the gas tankers, have no intention of revisting the tribology notes, but lube oils going into early shear was an issue in the field trials.

On the issue of engine runaway, these systems were developed over 20 years ago in Australia on mainly Japanese diesel engines which had Denso and Kikki in-line fuel pumps with cranky old throttle body governing, for example Nissan Patrol IDI motor. When you apply fumigation to ANY unthrottled motor motor there is always the potential of engine runaway particulary at part load when engine is responding to sudden reduction of engine load.

Bassplayer no intention of spoiling your personal enjoyment, just budget for new pair of engines and continue to play. However I get real scared when some poor smuck looking at this thinks concept could be viable and want do the same, or form an orderly queue as you put it! If anybody is even tempted to follow, and test your product liability insurance, I will have failed!

Another request is that we we do not wander off topic and go off on to LPG conversions of gasoline engines as relevant issues will be lost in a mass of smoke and windows.

 

[Assassin]

Latestarter:

My information is based on current testing of new engines, and i agree with the oil shear issues which have constantly arisen during the testing, it is a major issue and one people should be aware of.

My whole objective is simply to prevent people parting with huge wads of cash on systems proven not to work, and the expenditure of rectification work.

 

[Bassplayer]

OK. Very interesting replies.
What sort of engines have these tests been done on?
What %age of lpg has been used?
Have the tests been carried out using the same loads and revs as the stock engines, or have they been done utilising the extra power produced?
What sort of revs used and hours run for the tests?

 

[Assassin]

Do you mean what sort of engines are these tests being done on?

Most of the popular industrial, automotive, and marine engines.

Various percentages of LPG is being used, depends on which test is being done.

Tests are being done with the same loads, and the revs as they are stock engines, and within their defined or specified duty cycle, and with the increased power being used.

Exactly those revs and hours they would ordinarily be run for during their working lives.

 

[Assassin]

Lets ask more questions:

Are these tests being done with the support of manufacturers? in most cases yes, many utilise the information for future design scenarios.

How much involvement have the engine manufacturers: none, they receive relevant information and detailed analysis for the above.

Are these engines being used in real world environments? yes, without it the collected data would be worth very much less than a full evaluation.

 

[Bassplayer]

Various percentages of LPG is being used, depends on which test is being done.

This must be the crux of the matter. A low percentage is to enhance the burning of the fuel and therefore achieve the same power at the same revs for less fuel?
What percentage for what test carried out would be interesting and if it is all bad news with regard to oil shear, valve recession / burning etc have all these problems occurred regardless of the percentage of lpg?

 

[Latestarter1]

Bassplayer,

Lets get real here.....


You quoted yourself as an experienced engineer, please do not be offended but I suspect you are an extremely experienced and proficient technician, not an engineer.

The publicly funded diesel fumigation project was run by properly qualified engineers and I think that Dr Vinod Duggal one time Southampton University alternative fuels Guru was also a consultant. Engines developed were mechanical 6 and 10 liter, electronic 10.8 and 12 liter. Experiments were carried using fumigation from 5% to double figures.

The Cranfield paper is also worth purchasing.

Down to basics. Diesel injection systems unlike mechanical gasoline motors function under closed loop control, unless one introduces a secondary fuel source such as lube oil from failed turbocharger OR LPG, system then becomes 'open loop'.

The big deal with mechanical motors is knowing what the fuel pump is doing. You have real old Minimec fuel pump with RSV style governor and as I stated in earlier post (cruise control) you just set the rpm, governor in the pump adjusts the fuelling to hold the rpm set by the control lever dependant on what power the propeller is asking for, I will avoid the term throttle lever because that is a carryover from gasoline engines.

Other than taking an vital input from turbo boost pressure you know very little about the ACTUAL fueling being delivered by the pump as a dynamic of the propeller loading as control lever position is merely an indicator of required governor performance. This was always the issue with mechanical diesel engines, together with the fact that stepper motor controls were dropped real early on due to inadequate speed of response. Another very useful input as to exactly what is happening would be EGT.

Electronic engines are far easier and safer to control as you have all the data coming down the J1929/CAN data link, % engine load, boost, ambient air pressure, throttle position, rpm, etc etc. Notwithstanding all this valuble input LPG fumigation of electronic engines 'IS STILL OPEN LOOP' and therefore will always be potentially dangerous.

Rather than question others as to what test methods were employed, post me and I will be happy look at your dyno test results and point out where you are likely to run into big trouble.

I can understand totally where you are coming from, fumigation will totally transform a Ford Dorset, smoke will be cleaned up in a trice and motor will even sound sweet, akin to a common rail engine, as the faster moving flame front will take much of the 'crack' out of diesel combustion noise. You are not wrong in that the perceived advanantages are huge, sadly technology is full of big fat flaws.

 

[Assassin]

In addition to the aforementioned potential issues there are others which appear to have been overlooked, namely the additional risks of such systems and the resulting insurance issues, namely price hikes in premiums.

Insurance companies are tightening up, we are all aware of this, and one area now becoming popular is the additional risks of LPG tanks and systems aboard boats. Many LPG tanks have a certification for test for as little as 5 years, particularly those from the cheaper systems such as the Italian systems, meaning re-testing of the tanks every 5 years, this is not cheap. Insurers are taking the opportunity of "excessively loading" premiums, unjustifiably in many cases for marine installations due to these potential issues, and the fact they do not have to conform to the much more stringent regulations applied to motor vehicles.

Before even considering fitting such systems it would be wide to speak to your insurers to confirm premium rises and any conditions they may insist on.