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redynvre · 09-02-2004, 02:21 PM

Thanks Andy,

I think these lines must have been replaced not too long ago because they look really good and firm. I have to check the paperwork to see when.

Thanks John,

I will follow your direction. From the look of it, it seems that I don't need to remove the tire. I will be ordering the Chassis manual next month but I still want to take care of this before.

What would you recommend for a rear electrical fuel pump? It seems it will requiere a 15lbs pressure capacity from what I understand.

Thank you for the help!

Francois.

ALANSD · 09-02-2004, 03:21 PM

I crawled around under my 280 and looked for a rear fuel filter, did not see one. Anyone else have one on their smaller than a 345 unit? I plan to add one and will do so this winter.

thenewkid64 · 09-02-2004, 03:37 PM

Alan,

I have 2 filters.

One on the frame rail inside the pass side front tire. A second one in the carb. I carry spares of both. I know that peter added a marine style screw on cartridge filter right at the output of his tank. I am considering the same thing. The little frame rail filters seem to clog up really fast on mine

ALANSD · 09-02-2004, 04:34 PM

I did not follow the line all the way to the front, figured any other than at the carb woudl be in back.
I will look again, thanks.
I have seen a the screw on type at Jeg's. Guess I will invest in one of those.

74Argosy24MH · 09-02-2004, 05:02 PM

Quote:

Originally Posted by redynvre

What would you recommend for a rear electrical fuel pump? It seems it will requiere a 15lbs pressure capacity from what I understand.

15 lbs. is too high, it will hold the needle off the seat and flood the engine. 5 or 6 lbs. will do it. You need volume more than pressure, it is a long way through small lines from the carb to the tank.

John

thenewkid64 · 09-02-2004, 05:12 PM

Quote:

Originally Posted by ALANSD

I did not follow the line all the way to the front, figured any other than at the carb woudl be in back.

Mine has an AC1 AC delco sticker on it, just to offer a reference of what to look for. It is less than 6 inches tall.

redynvre · 09-05-2004, 05:18 PM

Hello all,

I looked again for the fuel filters, and I think there are only two of them:

-1 in the frame behind the battery compartiment
-1 in the carb.

John says volume is more important than pressure, which should be then at around 8lbs, but what is a good volume? It seems some of them go pretty high, 150gpH?

Thank you all for your help!

Enjoy your long Week end!

Francois

87MH · 09-05-2004, 07:53 PM

Quote:

Originally Posted by redynvre

....John says volume is more important than pressure, which should be then at around 8lbs, but what is a good volume? It seems some of them go pretty high, 150gpH?

Francois:

8 psi should be OK. If you have a carbureted engine, you just have to push the gasoline to the mechanical fuel pump......most 454's have a regulator built into the mechanical fuel pump which sends the "excess" volume of gasoline back to the fuel tank (this decreases the pressure to the float in the carb). This is not the case in newer fuel injection systems - they do not have a mechanical fuel pump.

150 gph should be fine - I have recorded a low of 4 mpg at cruise - figure 60 mph - this works out to 15 gph - I would not go too much less than 150 gph - at full throttle (taking off from a stop or pulling a steep grade) the 4 bbl carb is going to suck a LOT of go juice.

redynvre · 09-09-2004, 05:07 PM

Thanks! I will let you guys know how it went!

I just need to figure out how to wire the electric pump!

krowsea · 09-09-2004, 07:20 PM

Quote:

Originally Posted by shinola345

I had power when I first started to investage the problem. I've not had a chance to look it over today but will this afternoon. There are two connections on the oil sending unit. I assume one of them is for the pump, same color white. does'nt seem to be any power to the unit. I'll check the fuse box also. should be in the glove box.
Have a good weekend. lobsters are soft shell this month .

One quick thought, although you may have already verified this. The oil pressure safety switch is there for a reason. If the engine has low oil pressure, the safety switch won't allow the pump to deliver fuel. There's supposed to be a start bypass terminal, but on some older switches, if the oil level is too low, the switch won't open and the fuel pump will never run. Have you checked your engines oil level?

John-Boy

krowsea · 09-09-2004, 07:24 PM

Quote:

Originally Posted by redynvre

Thanks! I will let you guys know how it went!

I just need to figure out how to wire the electric pump!

If you can tell me the brand or model of pump (or color, red=Holley #12-801, blue= Holley #12-802 and so on), I can probably tell you how to wire it. If you're purchasing a new pump, make sure it's a 'rotary vane' type, not diaghram, and spend the extra bucks for a fuel pump relay, you and the pump will be much happier.

John-Boy

krowsea · 09-09-2004, 07:46 PM

Quote:

Originally Posted by redynvre

What would you recommend for a rear electrical fuel pump? It seems it will requiere a 15lbs pressure capacity from what I understand.

Thank you for the help!

Francois.

I would recommend the Carter # P4070, or similar. It's 72 GPH @ 4-6 psi. A carbureted engine only needs 2-3 pounds at constant loads. Even a Holey Red or Blue pump would be fine though. The Holley Blue pump is a very common pump on an RV, and delivers 110 GPH @ 15psi. It's capable of pushing fuel the entire length of the coach. Holley has been having some quality control issues lately though, so it's not my first choice right now. The maximum working pressure for any carb would be 7lbs, after that the pressure holds the needle and seat open and floods the carb. It's a good idea to keep the fuel pump pressure at or near the maximum though because under a heavy sustained load, the 2-3 pounds can drop to zero.

Most RV's that have an electric fuel pump usually maintain a mechanical pump mounted to the engine. This precludes the need to run a regulator, and is the reason you need to run a rotary vane style pump, which is pretty much all you'll find on RVs. The mechanical pump (which can pull the fuel from the tank) 'is' the regulator for the system. The electric pump, which can push fuel, but is lousy at pulling it, is used to keep the mechanical pump supplied. The mechanical pump will not allow over 6 psi to go passed it. The rotary vane style pumps are not only internally bypassing, allowing the extra pressure to bleed off, but can allow (some) fuel to pass through the vanes, drawn by the mechanical pump, even if the electric pump isn't working.

I hope this helps,
John-Boy

ALANSD · 09-12-2004, 03:28 PM

Found my fuel filter. It was inside the frame rail behind the battery-starter cable line and other stuff, no wonder I could not see it. Used my big drop light to shed some on the subject.
Replaced it and the carb filter, then spent two hours playing with the filler neck hose on the radiator. Had to remove the filler neck to get the hose replaced, the 3/8 screw that hold the neck on was tough to get to.
Next- flush and redo coolant, oil&filter,and ready to go again.

redynvre · 09-13-2004, 11:39 AM

Thanks Krowsea!

I will follow your guidelines when I'll choose my electrical pump. I will try to replace the mecanical one tonight.

The Electrical one will have to wait a little since I will have very little spare time in the next future. I sure hope to do it before Thanksgiving!

Does anyone know a good book that explain wiring and how to do it? I have zero knowledge on this matter!

Thank you again all for your help!

Francois.