• Welcome to the new SAOCA website. Already a member? Simply click Log In/Sign Up up and to the right and use your same username and password from the old site. If you've forgotten your password, please send an email to membership@sunbeamalpine.org for assistance.

    If you're new here, click Log In/Sign Up and enter your information. We'll approve your account as quickly as possible, typically in about 24 hours. If it takes longer, you were probably caught in our spam/scam filter.

    Enjoy.

Reproduction Fuel Pump- Continued problem

M

Mbgardner

Bronze Level Sponsor
I just removed the stock fuel pump. It has a spacer and 2 gaskets; THe repro from Classic Sunbeam does not come with the spacer.

Q1. Do I reuse the spacer?

Q2; Curt advised that the pump lever goes under the cam lobe. The wear spot on the stock pump arm is on the outside of the arm. That suggests to me that the flat spot on the outside curve of the arm goes against the cam lobe.

That's how I seem to recall it should go. The engine is in the car and very difficult to see. I can feel the lobe with my finger.

I test fit it without any spacer or gaskets. I had to lift the pump arm to get to fit on the studs. With the flat spot on the outside curve of the arm against the cam. I think with the spacer and gaskets, it should have the right clearance to operate in that fashion.

Thoughts? agree disagree.

Thanks. all replies appreciated. would love to get this going.

THanks again.
 
So I finally got the repro pump installed. The purpose was to eliminate the pump as the source of continued poor weber 32/36 DGV performance after rebuild; excessive fuel in the barrels during operation and continued fuel discharge into the barrels after shutting down the carb. In line Fuel pressure gauge indicated 3-4 psi. So i decided first to replace the pump.

The new pump arm is the same length as the repro one it replaced, so I reused the spacer and 2 new gaskets.

Took a lot of cranking to get fuel to the carb, but it finally started. I had my wife watch the fuel pressure gauge while I was cranking it. Had no pressure but then it started. Let it warm up a little. With some choke I checked the gauge and pressure was dead on 2 psi.

Thought i was golden. It was 80 degrees out so took the car for some shopping errands. Maybe 5-6 miles total, about 1/2 hour run time. Ran mostly ok. Still flat spot on hard acceleration into 2nd and third. I thought it was going to stall on the home stretch once. Made it home

It was idling fast so I popped the bonnet. Turn out the low idle speed. Got it to about 800 RPM. Idled pretty fine. Looked at fuel pressure guage. 0 psi. looked at clear inline fuel filter canister. Fuel was coming in in fits and spurts. Couldn't believe it was idling. Revved it up a few times. Performed ok from manual acceleration. but still 0 psi. popped off the air filter cover. Certainly had no flooding or excessive fuel squirting into the barrels as before. Parked it in the garage. and here I am.

I did squeeze the plastic fuel line between 2- 1" wide wood shims and vice grips while. The line was distorted a bit when I released the grips but was able to round it out to original shape. 3/4 full tank of gas.

Not sure what to do except remove the spacer from the fuel pump. The gauge worked with the last fuel pump and was rock steady at 2 psi before taking it for a drive and heating things up.

I suppose I could check it again cold in the morning. And take off the fuel line before the pump to see if there's adequate flow to the pump or that it is not plugged upstream


But am interested in any other suggestions.
 
pretty sure. it worked on startup. worked with prior fuel pump. and is consistent with observation of fuel dribbling into clear inline canister (after the the pump) fuel filter, i.e., 0 psi. when warm.. Like it's just the engine sucking in enough fuel to run. pump not pushing any fuel into the fuel filter then onto the carb.

Update;
Just started it cold. IMG_1436.jpgIMG_1440.jpg

First image at 1350 rpms ; still choked to run that fast. pressure at 2+ psi.
Second image a little warmer; pulled choke out 800 rpms. Note fuel level in filter canister in background (over the outlet to the carb)

So it seems like all is reasonable normal when cold. Problem i bet now is when warm. Seems to indicate to me that my next move is to install spacer on carb to intake to insulate float bowl from heat of engine. that was in the plan somewhere after installing new fuel pump.

Not sure what else could cause back pressure in the fuel line when warm. Someone mentioned something about the fuel tank filler cap, but that's so far removed from the situation, i can;t believe that's an issue. I never believe it sealed that well anyhow, other than to prevent spillover when full.
 
Do you have your fuel line routed the same way as you did before you did the fuel pump swap? Or did you change the routing? Maybe experiencing vapor lock issues. I try to keep my fuel line as far from the engine block/cylinder head as possible. That fuel pressure gauge is sitting almost directly above exhaust #1 and may becoming heat soaked.
 
I have not checked my fuel pressure hot, but it is 2 psi cold. It behaves exactly as you describe. The clear fuel filter is only ever about 1/4 full and hot idle the tiniest amount bubbling in at the bottom (vertical orientation of the filter). I can't figure out why it doesn't fill up and have no idea how it runs at idle. It runs very well, so I haven't stressed about it.
 
Is that a liquid filled gauge? With temp changes they give radically different readings. Underhood= temp changes
 
Have your gas tanks been cleaned and relined? If not you may be getting paint flakes in the line and/or clogging the outlet in the crossover pipe.
 
Seems like vapor lock. fuel line routed basically over the thermostat. same as before. oil-filled gauge. fuel filter was basically empty when reading 0 psi. 2 psi as pictured with filter nearly full but cold. tanks not cleaned and lined on my watch. was thinking that route but without moving disturbing the car parked hot 0 psi on cold start following morning 2 psi and full filter.

I will install spacer insulator between carb and manifold and maybe release the fuel gauge from the head bolt away from the manifold complex. and drive it. outside temp 60 degrees now and for the next week.
will report back.
how does one remedy vapor lock?
anyone think driving with the filler cap open will influence this?

thanks
 
Mbgardner said:
Seems like vapor lock. fuel line routed basically over the thermostat. same as before. oil-filled gauge. fuel filter was basically empty when reading 0 psi. 2 psi as pictured with filter nearly full but cold. tanks not cleaned and lined on my watch. was thinking that route but without moving disturbing the car parked hot 0 psi on cold start following morning 2 psi and full filter.

I will install spacer insulator between carb and manifold and maybe release the fuel gauge from the head bolt away from the manifold complex. and drive it. outside temp 60 degrees now and for the next week.
will report back.
how does one remedy vapor lock?
anyone think driving with the filler cap open will influence this?

thanks
Click to expand...
Todays gasoline doesn't provide any help with vapor lock, it makes it worse. Depending on where you live you might be able to find gas stations that offer 100% gasoline with no ethanol, I have some around my house. Around me it's only offered in 87 tho, so you should use octane booster to prevent pinging. Give that a try, it's the cheap easy fast route and yes reroute that fuel line away from the head.

I struggled with vapor lock for a few summers before I threw the towel in and went with an electric fuel pump. My vapor lock issue was at the mechanical fuel pump. Driving at highway speeds I was fine, but sitting in traffic or stopping for a few minutes allowed to pump to become heat soaked and the fuel would vaporize and I would stall out. The quick fix to get my started and moving again was to pour a little water on the pump and I would see the glass bowl fill back up.

My permanent fix was an electric fuel pump. I installed it at the back under the trunk. Best practice is to install the pump lower then the fuel tank so that gravity plays in your favor. Have not experienced since.
 
IMG_1462.jpegIMG_1462.jpegIMG_1462.jpegWent out for afternoon drive 40 mi R/T. 7mm spacer and 2 paper gaskets between carb and manifold. Cold start choked maybe 13-1400rpms fuel pressure 5psi
IMG_1460.jpegIMG_1460.jpeg8 min later 3psiIMG_1461.jpeg
After first stop maybe 1psi. IMG_1462.jpeg
Cat was hard to start
After 2nd stop. 0psi
IMG_1463.jpeg

IMG_1463.jpeg
Hard start
Then back home. Parked. Engine off popped air filter and took short video of still recurring condition fuel vapor rising In primary; flooding in secondary. Honestly the fuel bowl did not feel warm to touch.
Will post video when I figure out how to

IMG_1460.jpegIMG_1461.jpegIMG_1462.jpegIMG_1463.jpeg
 
Have you ever cleaned/relined the fuel tanks? It is a long shot, but could there be sediment in the crossover tube that works its way to the outlet when the car is driven - and the fuel is pumping - and then settles down when the car is stopped.
 
You must log in or register to reply here.
Back
Top