Fuel System Swap....

[1BADC10]

Well... it's been quite some time since I've lurked around here.

So... here's what's been going on (aside from family & career).

Truck's been down for nearly two months since I roasted another set of 3-4 clutches AND an input drum (4L60E). Well... the drum broke, but the clutches were in better shape than expected.










I knew something worse had happened when I saw most of my 3-4 clutches in the wrong place, after I pulled the input drum out of the case.






Well... upgraded the (modified) stock separator plate with a Transgo plate. Waiting on the arrival of a set of Borg Warner HE clutches & gasket kit (along with a vac-mod part). That should take care of that. Now, about that fuel stuff. I've been having issues with the truck dying on me after driving over an hour or two in the city. After one or two assumptions, it dawned on me. Right before it would die, the pump would be REALLY LOUD! Well, the external pump I put on during the original swap wasn't designed to be a PRIMARY pump. Doh! Didn't help much that it was an EXTERNAL pump either. Well... I'm in the process of changing that, and doing a much BETTER job at it. LOL


Took these out:





These came last Friday:





These were ordered Friday:







One of 'em arrived today from Kansas. The other is still in route from Illinois:






I couldn't wait to install one of the Walbro pumps in it. I'll be doing the same on the other. Remember, my '86 Silverado C10 was originally equipped with a Quadrajet 4-bbl carb'd 262ci 4.3L V6. The original SUs were not the same as the '87 (or later) model trucks that were TBI. Everyone that mentioned upgrade, kept recommending '90 - '91 Suburban pumps. It dawned on me last Friday that my uncle once owned an '87 GMC Sierra Classic (same exact body style as mine) before he gave it to my grandfather (who traded it in for an '01 Silverado ECSB before he passed on). Duh... same truck, same tank... SU will fit mine too.

So, there you have it. I'm dying to get my metal brick back on the street again.

[HarleyDave]

Great pic's, any chance you have part #'s? Are you going to swap out the tank switching manifold with an '87? for the pressure increase now that you are pushing fuel instead of pulling?

[1BADC10]

Great pic's, any chance you have part #'s? Are you going to swap out the tank switching manifold with an '87? for the pressure increase now that you are pushing fuel instead of pulling?

Selector valve is the same (or comparable competitor) model (see attachments). One must remember to change out the hose that connect between the SU to hard line, hard line to selector valve, selector valve to hard line, hard line to filter, filter to hardline (or in my case filter to fuel rail), etc... Otherwise, one may have hose failure. I thought it was interesting that the '87s still used those old style clamps, but then again, the fuel pressures were at about half the requirement of the Gen III requirements. Worm clamps (similar to the ones provided in the Walbro kit) will be replacing those older style clamps. The engineering comes when adding relays to the switch wiring to trigger one pump at a time. I'm drinking a Budweiser now, and about to put pencil to pad. I should have that worked out in a matter minutes. Maybe I'll redraw it when I'm done & post it up. LOL


*EDIT*

Walbro 255lph Kit
Driver Side SU - Spectra Premium (P/N: FG05M)
Passenger Side SU - Spectra Premium (P/N: FG05N)
**You can go with AC Delco SUs, but prepare to pay $300 (or as cheap as $275 with a wholesale distributor)**

[GasGuzzler]

I have a new, in the box 4L60 input housing if you need it.

[1BADC10]

I have a new, in the box 4L60 input housing if you need it.

I have a spare... thanks! The one I broke was a performance builder's piece. Surpised me when it broke, but pressure is important animal in the trans world.

Built this for working on it. LOL





Spare Parts...





Going back in to reduce headache with tuning.





Vertical work to be done here (drain pan will be placed under).






I covered the table surfaces with an old tonneau cover (for now). Formica (sp?) will be the permanent surface covering. It helps get the job done.

[1BADC10]

Amazing how clean these tanks actually are after removing 22 years of collective DIRT! LOL

NOT A SPEC of sediment nor trash inside the tank... AFTER 22 YEARS of being used & abused! That's UNBELIEVABLE!!!

Driver Side




Passenger Side

[ls182]

Hey I have a problem with my set up and maybe you can help. Its a Walbro inline but when I get to a little over 1/4 tank it starves of fuel and starts bucking. Can the in tank pump be adjusted lower to pickup more fuel?

[1BADC10]

Well... I hope you didn't do like I did and possibly vapor lock the pump by installing the filter b/t the tank and the pump. That was only one part of my (potential) issues. Another part of my issue was it overheating. I won't emphasize that my external pump wasn't meant to be a "primary" pump (secondary pump that came from a ProCharger kit).

Starving for fuel is strong possibility. These tanks are not sump-type tanks, nor have baffles in them. If you got WOT from a stop, and the truck squats, then all your fuel surges to the rear of the tank. To be expected. The SUs are already less than 1/4" from touching the bottom. That's about as close as you'll get.

[ls182]

My filter is up just before the rail after my fpr. Yeah I know all about the tank not having baffles cuz I see the fuel needle move like crazy with a little more than 1/4 tank lol. Just wondering about the in tank pump cuz it looks the same length as the stock one but the Walbro has a hose on it that looks like it could be replaced with a longer one. I guess I will do a little more research. Thanks.

[1BADC10]

The Walbro pump in my pic does come with a long hose, but I cut it to fit the sender without all the excess.