Fuel system variations and regulated return - Diesel Forum

Tom S · 06-14-2006, 09:14 PM

I have been reading up on old posts back from the Hutchinagusta days on the fuel system mods and have some questions for those in the know.

1. What was the final verdict on the increased flow through the stock filter with a regulated return having negative effects on filtration? If this is a problem what might be a good solution? I was wondering about returning more of the fuel from an orfice at the stock regulator location.

2. Is there any advantage to feeding the heads in back and having the return at the front. My though here was having the return at the higher elevation side of the motor to assist in removing air pockets.

3. Are there any gelling issues with the pre pump filters such as the racor or the dahl? Or even some of the other simpler prefilters that are used?

Thanks guys and I trying to school up on this before I do a system on my truck. I am looking at converting to a SD based system with a regulated return or something like Bean has.

Tom

bullridin_fool · 06-14-2006, 10:02 PM

on the 94-97's the fuel is fed into the rear and returned from the front so i would imagine it won't cause any problems. thats how mine are set-up.

my system is very similiar to beans, minus the fancy hoses. i don't know about the gelling problems as i just installed it in the spring. after winter i'll be able to tell ya.

Tom S · 06-14-2006, 10:11 PM

I have noticed that there are variation in how some of the regulated return setups work and was wondering what the logic was behind them.

Tom

KRP · 06-14-2006, 10:13 PM

I've never had a problem with gelling in my Dahl filter. I don't see any reason that it would be more likely to gel than any part of the stock fuel system. As for increased flow through the stock filter, I think another filter is a good idea but have no technical basis for this other than that you are moving more fuel through the filter than in a stock application.

Tom S · 06-14-2006, 10:19 PM

I think one of the big ones on the add on filter is to protect the pump. But I noticed that back when a number of guys were getting water out of the dahl filters when the stock filter never captured any water in the bowl.

Tom

ddog · 06-15-2006, 10:30 PM

[ QUOTE ]
a number of guys were getting water out of the dahl filters when the stock filter never captured any water in the bowl.

[/ QUOTE ]

Yes, saw that too and that was adding a Dahl to a stock system. A reg return system would probably make the stock filter's poor water separation characteristics even worse. If you are concerned with gelling due to your climate, Dahl makes a heated version as does Racor. Some type of improved filtration is mandatory I would think. Iknow some of the systems eliminate the stock filter housing altogether (Beddins, maybe others)which has the benefit of making room for the Aftermarket twin HPOPs etc if you think you may go that direction in the future. You may try to PM Hutch. He was on here not to long ago in response to the "what ever happened to hutchinaugusta" thread. Check the user list he probably still pops in everyonce in a while. There was alot of information on the Texastowncar site, but tried to get there the other day and some wierd stuff was at that URL.

clamgulch · 06-15-2006, 10:35 PM

Hutch designed it so that the regulator was in line BEFORE the heads and the heads had bleed down orifices in them. Installing an aftermarket regulator AFTER the heads could lead to back flushing the pump or worse, leaving pressure in the fuel rails that could bleed down around the injectors into the injector cups- sending fuel into the oil or filling a cylinder.

Tom S · 06-15-2006, 11:01 PM

Clam do you have anymore info on the Hutch set up. After a ton of reading I have not found it. I think that the Dieselsite setup may delete the fuel bowl but not sure. I hope Bob or Dennis jump in on this.

Tom

haul_n_horses2 · 06-15-2006, 11:27 PM

[ QUOTE ]
I think one of the big ones on the add on filter is to protect the pump. But I noticed that back when a number of guys were getting water out of the dahl filters when the stock filter never captured any water in the bowl.

Tom

[/ QUOTE ]I had 8000 miles on my truck before I put the regulated return on and I drained my OEM fuel filter regularly and never saw any water in the drained fuel. My Dahl was pulling out several tablespoon every 3000 miles. I no longer bother draining from the OEM filter housing.

My regulated return feeds the rear of the heads and goes to the regulator at the front of the heads. No problems. The Dahl filter hangs down behind the transfer case and when it is well below 0º I have never had gelling problems. Even after a prolonged cold soak no gelling issues and that is with a 2 micron filter. Keep in mind that the regulated return heats the fuel in the heads and returns it to the tank.

Tom S · 06-16-2006, 12:30 AM

Your old post was one of the ones that really got me interested in that Dahl filter. My current leanings are towards a Dahl and this type of Cat Filter as as secondary after the pump. Although I was turned on to some possible Cat water separators tonight. I was also leaning towards feeding the heads in back and returning in the front.

Tom

ddog · 06-16-2006, 01:10 PM

[ QUOTE ]
I hope Bob or Dennis jump in on this.

[/ QUOTE ]

<font color="blue"> Regulated Return</font> Fuel System Variations as a title would probably get their attention quicker for a look and response. Not sure how long you have to edit the title yourself (24 hrs) IIRC. Probably could get a mod to change it for you though.

Tom S · 06-16-2006, 01:36 PM

I changed it to add regulated return to the subject line. I have found there are two versions of that cat filter a 1R-0749 and a 1R-0750. One is a few inches shorter then the other. I may have to search around and see what cat has for a primary water filter/separator that would use a similar base.

Tom