Joffroi

I have a 1970 Cutlass SX. Almost everything under the hood has been rebuilt. The original 455 block still has under 100 new miles. I can cruise around neighborhoods but when I drive it more "aggressively" the engine starts sounding like its not getting gas. I can sometimes pump the gas and save the car, but other times the car just cuts off. The fuel filter has been replaced so I am thinking that this is a fuel pump issue maybe. Any ideas? If you all also think it is the fuel pump, where is it on the car? (New to the Cutlass Club)

Thanks

Del70

Nice car...in my opinion...it Sounds like the accelerator pump needs to be replaced

Joffroi

accelerator pump? I thought this was a straight shot mechanical connection from the engine to the gas.

svnt442

The accelerator pump is in the carburetor.

Joffroi

The carburetor was re-built the same time as the engine actually too :-/

Oldsguy

Then check the fuel filter, there may be one in the fuel inlet of the carburetor, or there could be an aftermarket one anywhere in the fuel supply line, you know, one of those plastic or metal canister type.

Joffroi

I'll double check that, but the previous owner had the filter on one of the things he recently replaced too

don71

You've said a lot of things got rebuilt or replaced, any chance the PO put a new gas cap on there? If so, just make sure its a "vented cap", thats what should be on there.

I agree that it seems to be fuel related.....er lack of fuel. There is an outside slight chance it could be ignition related. If none of the suggestions turn out to be right, it might be a cracked distributer cap....or maybe the rotor is just loosly screwed to the distributor shaft. Good luck.

silverriff

Yeah always double check these things yourself. Looks like the car has been well taken care of, but the P.O. may have done something incorrectly, you never know, especially the carb rebuild. You never know the P.O. or whomever rebuilt it may have messed with the accelerator pump, or not even replaced it to begin with.

silverriff

Also make sure the hard fuel line from the fuel pump (front lower passenger side of the engine) to the front fuel inlet of the carb. It is very easy to twist and crimp when trying to unscrew the line from the carb.

Chumley

Just curious, what is that pulley like contraption attached to the alternator bracket in the picture? Don't believe I have ever seen that ( at least my '70 SX didn't have it) Chumley

compedgemarine

Chumley, that is the cruise control vacume pod. dont see all that many these days as they tended to dry rot and eventually got tossed.

Joffroi

You're right... cruise control! alright!

olds425

You can pull the air cleaner and look in the carb while running the throrrle with the engine off, you should be able to see it spray then. Good luck.

Joffroi

Well, my Cutlass is currently at the garage. The garage called me back and told me that my engine was actually hosed and it was going to take a 6k repair / rebuild. Luckily, my co-worker knows the owner and arranged the prank call. They are actually looking at it now. Lets hope for a quick fix.

bccan

I had a similar issue w/ a 71 Cutlass years ago. Finally filled up a 2 litre soda bottle w/ fuel to supply pump. Problem went away so I knew it was in the supply system. Found that hose connecting tank to fuel line had softened up & was sucking itself shut in high flow/demand - uphill, heavy throttle. I would see if it feels soft or just replace it if it is old & see if problem persists or gets solved. It's a ten minute gamble + 6" of 3/8" hose.

Edit Note - If anyone uses this alternative fuel supply diagnostic technique, understand that w/ a couple of heavy throttle applications 2 litres of gas will provide a VERY limited, short range. Like about a quarter mile. Bring extra fuel or be prepared to hook chassis fuel line back up.

silverriff

Jeez I actually said "sh*t" outloud when I read that! Some coworker. I may be alittle sensitive about my cars, but I would have gotten off the phone and punched them in the face Well hopefully whatever they find isn't too bad. Hopefully you won't get the standard quadrajet answer I get around here in Baltimore....which is "It needs to be rebuilt". When I was having my q-jet woes, I took it to 3 different people and they couldn't get it to run right by adjusting the mixture screws, so they said " it needs to be rebuilt" Most garages (most) today don't have the time, patience, or most of the time, skill to properly diagnose a qjet. I guess it's because the 20 year old kid from Wyotec can't find the ECU to hook his scanner up to.

Joffroi

Update on the car. Apparently the fuel filter has got a bunch of crap in it (although the previous owner said he replaced it). They are going to need to replace it. I'm really hoping that the tank itself isn't rusting internally and also going to need to be replaced :-/. They are going to take it all off and check it out. I'll probably get the next update on the car tomorrow.

They also needed to do some expected turning to the carburetor and such

my72vert

In the fuel tank there is a sock type filter on the inlet tube. Sometimes it can collapse and cut off fuel flow when more volumn is needed ( full throttle ) I chased this problem for a couple of days back in the day when I worked for Olds as a tech.

sx455raidercelticfan

[quote=bccan;184561]I had a similar issue w/ a 71 Cutlass years ago. Finally filled up a 2 litre soda bottle w/ fuel to supply pump. Problem went away so I knew it was in the supply system. Found that hose connecting tank to fuel line had softened up & was sucking itself shut in high flow/demand - uphill, heavy throttle. I would see if it feels soft or just replace it if it is old & see if problem persists or gets solved. It's a ten minute gamble + 6" of 3/8" hose.

i had the exact same problem!!!!! it was so hard 2 figure out!!! my car would bog out, sometimes turn off, and studder, i found it on a fluke i had my girl giving it gas and i seen it close as soon as i replace it it ran great!!

1 more thing i try 2 never ever ever take my car 2 any shop, peroid unless i know and fully trust the person!!! im going 2 say that 80% of shops are rip offs!! i know thats harsh but its true!!! i took my 87 grand national in for a oil change because i was in a rush 2 get 2 reno and my rear end blew 30 min later! i swear they drained my rear oil because i told them i just wanted a oil change and ive seen alot of crooked stuff happen painting next 2 repair shops over the years, NO1 TOUCHS MY CARS ANYMORE!!!

Joffroi

Well, what I thought was contributing to clogging the filters was confirmed today. The previous owners let it sit so long that some moister was in the fuel tank and causing all shorts of mess. Its surprising since they spent all the money to rebuild the engine.

But they are going to need to empty and re-coat the inside of the tank. It will be about a week before I can drive my car around, but at least when I do... it will run smooth and strong.

Joffroi

After a lot of delays and finally getting the tank back, I picked up my car with the new fuel filters and lined gas tank. It runs awesome. Still "hiccups" a little in idle (but never dies) but runs just awesome. Drove it for about 40 miles yesterday at all speeds. :-)

Joffroi

After a lot of delays and finally getting the tank back, I picked up my car with the new fuel filters and lined gas tank. It runs awesome. Still "hiccups" a little in idle (but never dies) but runs just awesome. Drove it for about 40 miles yesterday at all speeds. :-)