Electric fuel pump question

[SunRader78]

I have a 1978 620 Sunrader motorhome, and am having a strong smell of gas in the cab after putting in a fresh fuel filter.

Stock Carb - All the CA compliant smog equipment intact. 

 

The truck appears to have been set-up from the factory with an electric fuel pump given the OEM looking brackets for the fuel filter and pump back near gas tank.

Previous owner put this pump in:   https://www.summitracing.com/parts/atx-e8012s

With a Max PSI of 9, i'm thinking this pump is pushing way too much gas into my carbs causing the gas smell.

 

Should I swap out the pump to a low pressure unit?  If so what is a quality part i should be looking at?

--or--

Would an inline Fuel Pressure Regulator set to 3 PSI do the trick?

 

Thanks in advance.

[Crashtd420]

9 psi is definitely to much.... 

And I dont like those type of pumps but people use them with no problems....

 

I personally am using a Carter p4070 electric pump with a Holley low pressure regulator 12-804 set to 3 psi.... I also installed a cheap inline pressure gauge just before the carb.....

 

Before I installed the regulator I was at 7 psi and it would flood and make the engine run real rich.... 

 

[Stoffregen Motorsports]

Sorry Crash, I'm going to have to disagree with you on your recommendation.

 

The Carter vane pump is a good pump, but they are noisy and overkill for this application.

 

A standard old Facet cylindrical type pump is more than enough to feed a stock L series. They are quiet and very reliable, and don't require a regulator. I believe they were even standard on certain Datsun models of the 70's and 80's - https://www.pegasusautoracing.com/productdetails.asp?RecId=2698&utm_source=google&utm_medium=cpc&utm_campaign=FAC-477060&gclid=EAIaIQobChMIupi1vL3C3QIVCxhpCh1gsQbfEAQYBCABEgJbT_D_BwE

[Crashtd420]

 

34 minutes ago, Stoffregen Motorsports said:

Sorry Crash, I'm going to have to disagree with you on your recommendation.

 

The Carter vane pump is a good pump, but they are noisy and overkill for this application.

 

A standard old Facet cylindrical type pump is more than enough to feed a stock L series. They are quiet and very reliable, and don't require a regulator. I believe they were even standard on certain Datsun models of the 70's and 80's - https://www.pegasusautoracing.com/productdetails.asp?RecId=2698&utm_source=google&utm_medium=cpc&utm_campaign=FAC-477060&gclid=EAIaIQobChMIupi1vL3C3QIVCxhpCh1gsQbfEAQYBCABEgJbT_D_BwE

 

All good , just saying what I used..... 

The one you show definitely seems better than what sunraider was looking at or I think currently has installed....

 

I used the Carter because it was recommended for the weber and was supposed to not need a regulator, but that was wrong.... I think it was more recommended for a multi carb setup than a single..... 

 

So sunraider most likely what stroffgren suggested would be your easiest and best choice for your setup.... But I would still use a simple inline pressure gauge to verify the output.... 

 

[SunRader78]

Thanks for the info.  

Since my original post, I have also been reading up on the mechanical pumps, but converting to mechanical adds another layer of modification to the fuel system. 

Advantages to the mechanical is that as RPMs increase, so does the rate of fuel being fed to the carb, whereas the electric pump is just a constant flow rate. 

 

Finding a different low-PSI electric pump seems like the most reliable solution.

 

Can anyone point me to a resource for wiring a safety cut-off for the electric pump incase of an accident it will shut off and not continue to pump fuel?

 

 

[SunRader78]

3 hours ago, Stoffregen Motorsports said:

A standard old Facet cylindrical type pump is more than enough to feed a stock L series. They are quiet and very reliable, and don't require a regulator. I believe they were even standard on certain Datsun models of the 70's and 80's - https://www.pegasusautoracing.com/productdetails.asp?RecId=2698&utm_source=google&utm_medium=cpc&utm_campaign=FAC-477060&gclid=EAIaIQobChMIupi1vL3C3QIVCxhpCh1gsQbfEAQYBCABEgJbT_D_BwE

 

Thanks Stoffregen. This looks like what I need. 

I only see one wire(+) going to this unit, but my current pump has two wires.

[Crashtd420]

1 hour ago, SunRader78 said:

 

Thanks Stoffregen. This looks like what I need. 

I only see one wire(+) going to this unit, but my current pump has two wires.

 

I'll bet they are just showing you a covering over the wires in that pic... either that or its getting ground from the mounting bolt....

you probably have a power and ground ... so If the pump only had a power input you would just put your ground wire to the mounting bolt....

[Crashtd420]

4 hours ago, SunRader78 said:

 

Can anyone point me to a resource for wiring a safety cut-off for the electric pump incase of an accident it will shut off and not continue to pump fuel?

 

 

I used a basic oil pressure sender/cuttoff... not sure what brand to recommend, I got an airtex brand off ebay... reviews were good, does the trick..

 

Be careful because the oil pressure sending unit on the datsun L20b is a BSPT threaded fitting and sends out a ground  signal when there is no pressure to turn the light on.. when the engine starts no more ground light goes out....

 

This is opposite of how some of the cutoff sending units are wired, which can easily be fixed with a relay, plus the one I got would used a starter signal to activate the fuel pump while cranking.. also they are generally an NPT thread...

 

[Stoffregen Motorsports]

The Facet pump I linked will need new fittings, and they are NPT, so have a look at your layout before installation and make sure you have the proper fittings, ie- 90 degree, etc.

 

The wiring, I would snip the pigtail off your existing pump and re-use it on the new pump. Whether or not you solder the connections, you should use heat shrink on the splices to keep the weather out. You don't want a bad connection on a fuel pump.