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Classic fuel hoses and fittings
#1

I am in the process of upgrading the Con Met fuel /water separators to Racor /turbine type units with replaceable filters .
I am currently casting about for the correct plumbing for the engine fuel hoses before removing them from the existing separator . The hoses from tank and engine have female swivel ends , thread is 1 1/16 -12  , which I believe to be 3/4 , size 12 ( on the racer it would be AN dash 12 ). I assumed the fittings would be JIC 37 degree , but the hose end clearly has SAE stamped on it , which I believe to be a 45 degree fitting . The JIC fittings are readily available , SAE not so much . Wondering if anyone could shed light ? 
Hope everyone is well out there !
Thanks,
Chris

1986 #89
VIN 007
Detroit 8V92 TA 475 HP
Allison four speed 
Chris and Sharon Hand
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#2

In my experience building generator set and power units, most fittings are SAE but not all.  It really is up to the engine manufacturer i.e., Cummins , up until recently , used 45 degree SAE fittings and hose with the AI designation whereas the AII hose and fittings used 37 degree fittings.  Most SAE fittings have a groove cut in the nut around the circumference.   Cummins and Detroit used fittings from Stratoflex, now a division of Parker Hannifin and designated as 213 with a DOT compliance.  

A lot has changed since I retired but your classic will likely have 213 hose and fittings with 45 degree.  Many suppliers stock SAE fittings and finding them is not difficult.

Gordon Jones
2000-45'-2slide-#567
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#3

Thanks Gordon , I removed the lines to the fuel / water separator for the engine , they are both 3/4 hose with female swivels, SAE size 12 . The size 12 SAE threads are 1 1/16 - 14 , whereas the JIC 12 and AN Dash 12 are 1 1/16 -12 . Evidently threads are the same across the three designs in other sizes .
I was able to source fittings locally , we'll see how the new separators work .

1986 #89
VIN 007
Detroit 8V92 TA 475 HP
Allison four speed 
Chris and Sharon Hand
Reply
#4

those old separators were problematic for sure. i ended up having to seal the bottoms with plugs to get them to stop leaking.

wise choice to replace them. there were two of them on my 90. one for the engine and one for the genny. my 90 had two tanks side by side that were plumbed together and i always left them together. 330 gallons total.

tom

2002 45'8" Newell Coach 608  Series 60 DDEC4/Allison World 6 Speed HD4000MH

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#5

Okay , I now have the new fuel /water separator for the 8V92 plumbed and filled with fuel . A little apprehensive about attempting start up .
When I removed the hoses from the original ConMet separator there was only a slight amount of fuel in the lines although the separator felt full . Both hoses go upward , head in their respective directions . The engine had been started and warmed up a few days prior to removing hoses . I am concerned ( terrified ) about getting air into the system , but it seems to have been working this way . The primary and secondary spin on filters at the engine have not been disturbed . 
I am in the middle of a very lengthy fuel aeration /stalling problem with the generator ( will post in appropriate area ) , would rather not have another nightmare ....
Appreciate any input !
Hope everyone is well ,
Thanks , Chris

1986 #89
VIN 007
Detroit 8V92 TA 475 HP
Allison four speed 
Chris and Sharon Hand
Reply
#6

I am guardedly optimistic that I have turned the corner on the generator,  having replaced the lift pump and sealing washers , etc . 
But now...
In keeping with 2020 , I have a fuel delivery problem to the Detroit 8v92TA , Silver mechanical .
New fuel /water separator,  Parker 1000 clone .
New primary and secondary spin on filters , Luberfiner. Old filters Fleet Guard . Primary somewhat "blacked", secondary looked pretty bad .
Fuel /water separator replaced first , engine started prior .  Old ConMet units had sludge in bowls , I'm told algae .
I should note that the coach has not been driven in almost a year,  started and warmed up at intervals , about five weeks being longest while compressor and alternator jobs were going on. 
Noticed unstable idle after separator change , might have been present before , but I was hypersensitive after changing separator. Engine wasn't " hunting " , would just drop to about 350 rpm from the normal 550 / 600. I could ease the throttle on slightly,  up to 1k rpm , then back off and idle would settle to 500 for a minute or so.  
Changed primary filter,  new one filled with fuel .
Started , ran 10 minutes.  Idle as before .
Next day , started , warmed up 15 minutes,  shut down,  changed secondary filter , new filled .
Restarted immediately,  idle issue unchanged .
After a few minutes engine not sounding strong at all , throttled up , would Rev to about 1500 , then faltered and would only turn 1k , max .
Next day , engine wouldn't start . 
Fuel present in separator bowl .
Per Detroit manual , using electric pump plumbed into secondary filter mount , pumped about a quart of fuel into system .
Engine started right up , strong idle . After short time engine faltered , I switched off .
Next : plumbed electric pump to engine fuel pump inlet hose ( after priming ) , inlet for electric pump into 2 1/2 gallons of clean fuel .
Engine fired up,  sounded great .
Fuel level in 2 1/2 gallon container dropped rapidly  (fuel returning to main tank ) , I chased it with more fuel . Once warmed to 130 degrees or so I fed throttle in lightly,  revs went to 2100 quickly ( don't like revving with no load, got away from me ) .
Maintained 1500 rpm with light throttle .
Reconnected plumbing as normal , primed , same issues after a few minutes. 
Disconnected both ends of hose from separator to primary filter , blew through it , sprayed fuel in compartment. 
BTW , on this one at least , the hoses in and out of the separator cross before heading to front /rear , hose at rear of separator heads forward to tank . 

Yesterday,  pressurized fuel tank via vent , no joy .
Fuel level in tank is about 8 1/2 inches , wondering if this too low for the vacuum of the pump to lift .
Presume there is a check valve somewhere that could be sticking . 
Very wordy and much to unpack , I know , any input appreciated.  I have a chance to make the finals if I can get this going , otherwise it will be a wash for this year , try for Spring race '21 .
Thanks , Chris.

1986 #89
VIN 007
Detroit 8V92 TA 475 HP
Allison four speed 
Chris and Sharon Hand
Reply
#7

My check valve was located 1.5 feet from the tank and we put the new check valve in the engine compartment when we replaced the fuel hoses.  When I had a similar problem as yours we suspect there was an air leak in the fuel hose and/or a clogged check valve.
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#8

Chris,
Not sure if this pertains to your situation but do you have DDEC on the 8V92TD?  Take a look at this thread that happened to me just the other day......http://newellgurus.com/showthread.php?tid=5756.  In the early stages of troubleshooting the engine did start back up but died again.  As you can read I suspected fuel related issues and took my check valve to the Detroit Shop to get a new one....it checked good in their shop.  Given what I was seeing, similar to your situation, this was most likely the culprit.  The Detroit tech. suggested several things to look at, he was extremely helpful and customer orientated.  One of which was the DDEC power.....he suggested things in order of cost escalation i.e. the cheapest first. 

Resetting the circuit breaker fixed the issue as today I took it out for a 25 or 30 mile test drive....all worked great.  I have new breakers coming and will be replacing them next week.

Steve & Doris Denton
45' Newell #525, Bath & Half
2014 Honda CRV Toad
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#9

This one isn't DDEC , mechanical only . I located the check valve yesterday , 1.5 ft from tank outlet as stated . Newell  provided an access port for the tank fitting , but valve looks tricky. Removed hose from tank , connected electric pump and pumped fuel from separate container . Watched bowl on separator,  air bubbles coming through the turbine . Once bubbles stopped I pumped a little while longer , then reconnected to tank . Primed at secondary filter previously . Engine started up , healthy idle . Ran probably ten minutes, I was beginning to think it was on it's way when tone changed . 
If I can get fuel delivered ,I want to try filling the tank and pumping more fuel forward to try and purge all air . After that , new hoses and check valve . And ball valves .
Thanks for input , any comments appreciated. 
Chris

1986 #89
VIN 007
Detroit 8V92 TA 475 HP
Allison four speed 
Chris and Sharon Hand
Reply
#10

Just two generic comments. Not trying to be a smart alec. Take a hard hard look at what you changed. If the new separator is leaking air into it , or any of the touched fittings is leaking then it would cause what you are experiencing. I am sure you have rechecked the install, but wouldnt hurt to look again.

Second thought is to put your aux priming pump into the system temporarily. Run the inlet from the tank instead of a fuel can

Richard and Rhonda Entrekin
99 Newell, 512
Subaru Outback Toad
Inverness, FL (when we're home Cool )
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