binfordm715 : Now what do I do?! (Holley 1920 rebuild)

Now what do I do?! (Holley 1920 rebuild)
Post by binfordm715 on May 23, 2006, 12:23am

Well now what?!

http://img210.imageshack.us/img210/4...ley19205ua.jpg


The "pump diaphragm & rod assembly" I get in the kit is on the left. The old one, with the now torn-up gasket material, is on the right. See what's on the paperwork that came with the kit? That's right....just like mine. 'Course the NOS kit is probably as old as I am (eBay find), though unopened. I'll see if NAPA can do anything for me.

Also, the fuel input is different. There's a "fuel inlet seat 'O' ring seal" that I have on my "fuel inlet needle & seat assembly" that this kit doesn't include. At least that part isn't on the drawing too!

No one has any quick-n-dirty ideas about dealing with this, do they?

Re: Now what do I do?! (Holley 1920 rebuild)
Post by brute4c on May 23, 2006, 9:41am

Does Al's truck have a 1 barrel? How good are you at stealthly carb work?

Sorry to hear it Tim...that sucks...I hope there is an answer out there that isnt a big headache...

Who did you get the kit from? Was it an individual or company? Might help others avoid the issue...

Tried AB Linn? Cant say it will help but cant hurt....

Re: Now what do I do?! (Holley 1920 rebuild)
Post by robsgp on May 23, 2006, 8:31pm

Got my NOS kit from Saturn Surplus. It had the correct pump diaphragm and rod assy though I came awful close to shooting that little BB across the garage reassembling it. The kit also came with a complete fuel inlet needle and seat assy with a gasket by the hex head and o-ring on the body. My big question is where the pump rod sticks out the back of the carb there is a little plastic cam that looks broken off and nothing attached to it??

Re: Now what do I do?! (Holley 1920 rebuild)
Post by luckypabst on May 23, 2006, 10:24pm

That's the pump cam, seems to be commonly broken. Mine was and Jon hooked me up in my time of need. Probably your best bet is to find someone with a spare that dosen't mind parting with the cam.

Chris

Re: Now what do I do?! (Holley 1920 rebuild)
Post by binfordm715 on May 24, 2006, 1:11am

You had me scared there, guys! But it looks like my pump cam is in good shape. Looks new, I notice.

http://img231.imageshack.us/img231/8...closeup4el.jpg

Well, there's one thing that went my way!

Anyone got a spare O-ring for the fuel inlet needle and seat assy? I can get one at NAPA for $0.99, plus $7 for shipping!

Re: Now what do I do?! (Holley 1920 rebuild)
Post by brute4c on May 24, 2006, 9:38am

Thats the accelerator pump arm...I have seen a few in a white/yellowed color...

When I bought my truck it had a dead spot off the line...traced to the acelerator pump arm being broken...so I found a junkyard 230 with a good pump arm and swapped that on...lasted about 2 years, then it broke...so then I had to buy a "rebuilder" carb with a good arm on it to get another one...BUT instead of mounting that arm to the carb, thinking it would only break again, I took it to the local machine shop and had them make one out of aluminum...no more problems.

I sent the stock type arm to Chris...the aluminum one went with the carb out east when I changed to the 2 barrel setup...someone else needed the whole thing.

Re: Now what do I do?! (Holley 1920 rebuild)
Post by robsgp on May 24, 2006, 8:00pm

Mine was the yellowed broken plastic variety. Maybe I'll try making one. Great information thanks. BTW, Tim I do have an extra o-ring. Evidently my kit came with the whole assy and o-ring and gasket. You can have it. I just signed up to attend FE or I can mail it if you want it faster. Just email.
Rob

Re: Now what do I do?! (Holley 1920 rebuild)
Post by binfordm715 on May 25, 2006, 12:11am

Hey, if you need me to pull that cam thing off of there to trace it and measure it, just say the word. Wish I had a spare for ya!

BTW, NAPA was able to scare up the correct pump diaphragm & rod assembly from a store in Seattle, so that's done. Just that pesky gasket that had me held up.

I'm trying to do some research on this blasted thing to come up with some NAPA part numbers or something. When I go back to hound them tomorrow (actually, to take a digital pic of that dummy machine gun), I'll see if they have that cam available too.

Re: Now what do I do?! (Holley 1920 rebuild)
Post by robsgp on May 25, 2006, 8:35am

It went in the mail box today. Thanks for the offer to trace the part, but the picture you posted is so clear, and mine is just broken off where the rod from the accelerator attaches. I'm hoping to guestimate it and use a piece of coat hanger to connect it. If you do run across one though, I'd be very interested in buying it.

Re: Now what do I do?! (Holley 1920 rebuild)
Post by jeepistdougiowa on May 25, 2006, 9:17am

I have a couple partially parted out carbs, if those parts are still on them I'll bring them to the FE.

Re: Now what do I do?! (Holley 1920 rebuild)
Post by brute4c on May 25, 2006, 10:41am

I think I have a pic somewhere of the cam off the carb...lets see here...yepper...with the linkage arm and C clip...

http://www.m715zone.com/jonmisc/acclink.JPG

Re: Now what do I do?! (Holley 1920 rebuild)
Post by binfordm715 on May 26, 2006, 12:41am

Grrr!

Dropped part of it when I was cleaning it today. Fell to the floor and broke a plastic part. Not that cam part though. Anyway, I don't want to talk about it right now....

Re: Now what do I do?! (Holley 1920 rebuild)
Post by brute4c on May 26, 2006, 9:12am

sorry to hear that Tim....wish I had a parts bucket for those anymore...

Re: Now what do I do?! (Holley 1920 rebuild)
Post by tomkirkman on May 26, 2006, 1:05pm

That's the cam for the accelerator pump diaphram. Without it the engine will bog upon acceleration until engine catches up and pulls more fuel into the intake. The purpose of it is to squirt a little raw gas into the intake so you don't have an overly lean condition when you open the throttle.

The performance difference between an M715 with a good one and a broken one is night and day.

Re: Now what do I do?! (Holley 1920 rebuild)
Post by binfordm715 on May 26, 2006, 1:13pm

Yup. That's about the ONLY thing that went right for me!

Looks like the Forest Service had replaced it recently.

Re: Now what do I do?! (Holley 1920 rebuild)
Post by thetroublemaster on May 26, 2006, 2:50pm

Tim, go to a hobby store and get some thin non gap filling CA glue. I just assembled some stuff with it this weekend and aside from gluing the part to my fingers several times the bond is very very strong. I am sure it would work for you.

Re: Now what do I do?! (Holley 1920 rebuild)
Post by robsgp on May 26, 2006, 3:55pm

Well it's a little clunky... We'll see how it holds up.

http://usera.imagecave.com/robsgp/m715/IMG_0526.JPG

Re: Now what do I do?! (Holley 1920 rebuild)
Post by binfordm715 on May 26, 2006, 6:29pm

Cool fabrication there!

No, Al... I don't think I can glue this piece!

http://img232.imageshack.us/img232/1...920008a1cf.jpg
See the crack in it? Pretty small compared to the giant quarter!

http://img141.imageshack.us/img141/4...920009a2st.jpg


That's the part I dropped.

However, Brandon (rpgdeity) is bailing me out!!!
He swapped in a 2-barrel carburetor on his truck, so I'm going to pick his old 1920 up to use that part. Hopefully I won't drop it when I clean it up first!