Sputtering to a Stall

[Marshall]

Thanks guys.

I checked the ignition coil today and it read 1.9 ohms primary resistance - from what I found online anywhere from 0.4 - 2 is a good reading. And secondary resistance read 8,600 - and 6K - 15K is good from the site I looked at.

I will take out the old metal inline fuel pump, and either run with nothing for now to accurately test the fuel pump, or put in a new one. I'm assuming this WIX one will suffice? : http://www.amazon.com/gp/product/B000C9 ... sr=8-2#Ask I'l also grab the glass bowl filter while I'm at it.

If I'm lucky it's just this old inline filter that causing the problem with a blockage. I'm assuming it's not the fuel pump since I just got it rebuilt by Then and Now Auto.

Next, I'll move onto the carb. When taking this apart, will I need to buy new gaskets to put back together? most likely?

[Marshall]

*** Update on carburetor - I found out from the previous owner that she just rebuilt it, this past March. So I could assume with some certainty that it's functioning as it should.

I think the pump is not working properly, it's definitely not shooting out by any means. Culprit = old metal inline fuel filter - (I hope). please, please....

[Marshall]

Alright, SUCCESS!!

I pulled the old filter and put in a new clear one in it's place, filter innards for the glass bowl are on the way. I took apart the carburetor and cleaned it, this was most certainly the problem. I found the manual for the Rochester Carb and read through the step-by-step - then a little FaceTime with Cameron, and viola! Clean carb... And all the brass components and gasket are new, and look great, so that's a plus.

When I took off the old metal inline filter, something sizable inside was shaking around, maybe some part of the filter broke loose and failed, hence sending all the debris on to the carb.

So, problem solved! Thank you all for the help, no way I would have figured it out on my own. I'll add the carburetor to my growing list of things I now understand and can take apart and reassemble.

A few before and after pictures of the inside of the carb.
BEFORE:

unnamed-1.jpg

AFTER:

unnamed.jpg

NEW inline filter, BEFORE the fuel pump.

unnamed-2.jpg

So. I fired it up and was going to take it around the block to see how she runs... BRAKES ARE STUCK. They aren't fully locked and stuck, but very close to it. The pedal is very fully hard and only has about 1/2" of travel on it. I rebuilt the MC with the Corvette rebuild, and all the wheel cylinders are new. All the adjuster nuts are fully backed out. Prior to this they were just fine, I put probably 100 miles on the truck since doing the brakes. Any ideas on what caused this? and more importantly how to fix it? It's like the brakes are applied all the time, and there isn't the capability for them to travel back to the unexpanded state. Is there an outlet somewhere to release pressure that might be clogged? or a valve? What am I missing?? THANKS!!

[rjiggy]

Marshall,

Did you remember to install the original spacer between the fuel pump and the block when you put the rebuilt pump back in?

Also, Faux40 had an issue with his rebuilt pump and ended up doubling the spacers to get the pump to produce.

A quote from John's post:

"I also called Then & Now about the fuel pump -- won't pump when mounted with one 1/4" spacer; pumps fine with two 1/4" spacers. T&N will modify the pump's push rod "under warranty" or, he suggested making a thicker spacer and simply running that -- even when I suggested that it may not actually be the correct pump in the first place. Good folks there"

Rick

[RiverPatrol]

So. I fired it up and was going to take it around the block to see how she runs... BRAKES ARE STUCK. They aren't fully locked and stuck, but very close to it. The pedal is very fully hard and only has about 1/2" of travel on it. I rebuilt the MC with the Corvette rebuild, and all the wheel cylinders are new. All the adjuster nuts are fully backed out. Prior to this they were just fine, I put probably 100 miles on the truck since doing the brakes. Any ideas on what caused this? and more importantly how to fix it? It's like the brakes are applied all the time, and there isn't the capability for them to travel back to the unexpanded state. Is there an outlet somewhere to release pressure that might be clogged? or a valve? What am I missing?? THANKS!!

It sounds like the master is building too much pressure. I just talked to someone else recently who had a similar situation. He had had a shop rebuild his master, but when he drove the Patrol to work by the time he got there the brakes would be locked up. If he cracked the brake line and released the pressure then the brakes were fine, until his next trip. I don't know what would cause that. I wonder if it might have something to do with the amount of shims between the master and the firewall? I seem to remember having to add or remove those shims for a similar problem.

Congratulations on the discovery in the carb. It's a good thing you're confident with tinkering with that stuff.

[Esteban]

Congratulations on solving the fuel/carb problems.

... I wonder if it might have something to do with the amount of shims between the master and the firewall? I seem to remember having to add or remove those shims for a similar problem...

Marshall, as a temporary or troubleshooting measure, backup the two nuts that secure the master cylinder, and see if that reliefs the pressure. As RiverPatrol mentioned, some shims might be missing. Did you install the piston from the Corvette master cylinder rebuild kit? If so, there could be the reason.

As Ron mentioned in your other thread: The piston in the corvette kit is an exact match other than the hole where the rod goes is not drilled as deep as the Patrol piston. I would only use the Vette piston if the Patrol piston was damaged. All you would need to do is shorten the original rod, this would be a last case scenario. You still need to free up that rod in the original piston though

[Marshall]

Thanks!! I did use the piston from the Corvette build. I've taken it apart and put in the original piston and swapped on the new rubbers. I also found a metal shim in my box of stuff from the previous owner, it's a half of the footprint of the mc where it bolts to firewall. I'll use this as well on the top of the mc to make the rod and the brake pedal more of a 90 degree junction.

I think doing both these suggestions it'll be fixed! Then I can actually use my brake adjusters and not just have them fully backed out.

[Marshall]

Update:

Brakes: Put in new master cylinder rebuild.... BUT, the cylinder plunger seal had a little knick out of it, and right on the edge. I put it in HOPING the little knick out of the rubber seal wasn't large enough to leak and relate pressure. But, unfortunately it did leak, and didn't hold pressure. SO, I was back to needing another full rebuild just to get a new rubber gasket. No one wanted to break up their rebuild kits and just sell me the seal. (I tried calling all Corvette shops I could find in the US). I was frustrated and didn't want to pay the full price for another rebuild kit, and didn't want to wait for shipping. So, I did a Google similar image search on the rebuild kit. I found many other kits that 'looked' the same, but something was off. After many dead ends, I finally found out that from 1951-1966, (I think), that about 20 GM cars had the same master cylinder dimensions. AWESOME! So I called a few shops to check on the list of cars I found it to be compatible with. I ran down the list and landed on a 1963 Chevy 1/2 Ton Pickup. This was all the same dimensions, and the rebuild kit seemed the same. So I picked it up from my local O'Reilly's for only $12. Installed it and it works! But, like the Corvette rebuild the cylinder needed to drilled out several mm for the pushrod to sit accurately.

Here's all of the other cars I found that I think all have the same master cylinder, (or at least the same rebuild kit):

1955-57 Chevy Bel Air, 150, 210, Nomad
1962-66 Bonneville, Catalina
1951-63 Chevy 1/2 Ton (what I used, and can vouch that it fits and works) BRAKEWEAR Part# 22961 NAPA Part# UP253
1965-66 Chevelle

So, now my brakes are set. (for now)

Back to fuel issues. After putting everything back in with new inline filter and a clean carb - it would run for about 30 seconds, then stop. I took apart the carb again, ran some diagnostic bench tests. The float needle was getting stuck, therefore preventing fuel through. So I saw the brass fitting was a bit snug, the needle brass casing is square, and fitting into circular space. I lightly sanded down the corners of the square - seemed better, and was't sticking. Reinstalled, same result. Would run for 20/30seconds, then stall. I took the carb back off. The rubber tip of the float needle was still sticking. So, a buddy of mine swapped in an aluminum tipped needle for me. Reinstalled - it would run, and then stall. This time ran for longer. I checked the carb and it was smoking white smoke. Looked up possible causes: now it seems the float needle isn't sealing properly, therefore letting in too much fuel and flooding. First not enough fuel, now too much.

So... My plan is to get another float needle, (one that has a little hook on the top), and drill a hole in the float arm and attached that sucker to it. The needle tip will be rubber, like original one, but with it connected to float arm, it'll prevent it from getting stuck closed. Is this the best solution? Any ideas out there? Thanks!

[RiverPatrol]

Rob is the carb meister, he should be able to tell you if you're headed in the right direction.

Great post about the master cylinder compatibility.

[moore_rb]

Marshall, it sounds to me like your float level and float drop may be set incorrectly. If the float level is set too high, then the volume of fuel allowed into the bowl can force the floats to jam the rubber tip of the needle up into the seat. It can also cause the flooding you are seeing.

I would have to look up the float level and drop specs for your Rochester carb- I have them around here somewhere, but that is my guess- to become jammed up into the seat, that needle is fighting both the force of the fuel pressure, as well as the force of gravity... It seems really odd to me that it could become stuck that easily...