SUs and pumps

[240260280]

2 hours ago, siteunseen said:

  When it stops your breathe the top of the float should be .55" from the lid.

 

I do the same but with two steps:

1. Make sure the top of the float is parallel with the metal beam attached to its top.

2. With the lid off, upside down, and in front of your face, blow into the gas inlet while moving the float. It should block your breath when the metal beam is parallel to the top of the lid. If not, bend tang until you get it right,

Edited March 27, 2018 by 240260280

[Zup]

 

18 hours ago, Richard McDonel said:

the problem seems to be that the new,  Kyosadenki mechanical pump has stopped pumping.  There is fuel to the filter side, but none comes out the carb side.  Anyone know of any reason why a new pump would fail?  I  took if off the car and bench tested by pushing the lever while hold a thumb against the inlet.  Sounds OK.

I'm no expert either but a new fuel pump should not "go bad".

Some thoughts--

You mentioned the engine is a rebuild---did you do the work of re-assembly?

Double check your eccentric on the end of the camshaft. Make sure it is securely tightened by the camshaft bolt. The eccentric is what gives the fuel pump lever arm its pumping action.

Make sure the fuel pump lever arm is riding on the eccentric when you have the pump installed.

[Captain Obvious]

1 hour ago, Richard McDonel said:

Yes, that's what I mean.  Fuel came out the back as I removed the pump and gasket from the head

Well that's not good. Regardless if the diaphragm looks OK or not, something is leaking there and it either needs to be addressed or replaced. Sucks that something like that would happen with a new pump. Is it a new-new pump, or a new-old stock pump? In any event, a ruptured or leaking diaphragm there could account for both issues. The leak and the lack of function.

I guess it's conceivable that a stuck closed output side check valve could allow the pump to suck in a charge from the inlet side, but then force that charge out of a hard to see, small hole in the diaphragm.

And, yes, change the oil. You don't know how much went down there.

[siteunseen]

2 hours ago, 240260280 said:

I do the same but with two steps:

1. Make sure the top of the float is parallel with the metal beam attached to its top.

2. With the lid off, upside down, and in front of your face, blow into the gas inlet while moving the float. It should block your breath when the metal beam is parallel to the top of the lid. If not, bend tang until you get it right,

I tried explaining that in that other gut wrenching SU float level thread.  Here's the picture I used to try and get the very basic setting.

And the bendable tang the needle rides on, the beginning of the yellow arrow in my picture, should be more rounded than straight.  It should look like a speed bump instead of a ramp.

 

[Richard McDonel]

Cap't.

With respect to your new-or-old question, the pump came new in a box along with a rust bucket 240Z that was beyond restoration.   The previous owner in rust-belt Ontario had apparently decided that he had this neat old car that could be restored - all he had to do was buy all kinds of shiny new parts and bolt 'em on - just like on the "reality" TV shows.  So in my car, I now have a new clutch, wheel cylinders, brake discs and drums, brake and clutch cylinders and lines,  water pump, oil pump, u-joints, shocks, tie-rods, etc.  Hopefully it's on the road later this spring.  

Many thanks for your advice and assistance.  

[Captain Obvious]

My pleasure and hope you get it figured out soon. Here's to hoping it's as simple as a defective fuel pump.

Neat story, but out of curiosity, is the rust bucket "beyond restoration" the car you're working on getting running, or was that a second car included with your car as a parts donor?

[Richard McDonel]

Actually, it's #3.

#1 was my son's - about a dozen years ago.  He thought he could restore it at the same time he was relying on it for day-to-day transportation.  You can guess how that worked.  I bought it off him so he could make a down payment on a car with just one special thing:  a warranty.  My intent was to restore, but between running two businesses and writing a book it took me years to get to it.  I had the local hot-rod fraternity's auto-body shop look at it and he said it would cost a minimum $20k, and maximum $40k.  That wasn't going to work.  That's when I went internet shopping and found #2,  the "100% rust free" '73 north of Toronto - that's about 2,500 miles from me.  It turned out to be a fraud; for instance the rockers were stuffed with steel wool and fiber-glassed over. Pictures looked good.  It did, as I mentioned earlier, come with a  pallet-load of  parts, some of which I'm going to be offering for sale once the present car is up and running.  So I stripped and scrapped that body.  By now I had rebuilt my son's engine, and really wanted to get on with it so I decided to search the 'net daily for a "rust free" in a desert climate.  I figured if I could find three at one time in the same area, I'd fly down -- no more long distance believing everything the seller said.  I did find three in Phoenix and went to have a look. 

The first was another fraud. The guy told me if I sent him the money, he would save me the trouble of going down, because his son was driving a truck north and would meet me at the border. When I got to Phoenix, the guy never answered the phone.

Second car was pretty decent but it did have some rust bubbles above the doors and quarter windows. Not sure how that happened.  

The third car was a '71 Series 2 at a repair garage and was being sold because  the owner had died.  It ran rough, and the interior was baked from four decades in the desert, but the body was sound.   When I asked about rust the guy put it on the hoist, handed me a trouble light, and said "take as much time as you need."  I looked, bought, and flew back home.  A few weeks later I re-habed  my old race car trailer, hauled it down there, picked up the 240, and came home.  Driving alone I did 5,200 km (3,200 miles) in five days, four hours.  As an aside, that road trip reminded me of how much more there is to see on the road as opposed to  flying.  If anyone wants to take the trip, hopefully in a Z car, I recommend turning east off Interstate 15 at Cedar City, Utah onto Hwy 14 (big signs "Not recommended for semi-trucks") and connecting with Hwy 89 south to Phoenix.It is a road meant for sports cars, it rises to 10,000 feet altitude, and is quite scenic. So that's the story of Z Car 28726, which I hope to have on the road later this spring.  

 

[Captain Obvious]

Well that's an even better story! Hope it has a happy ending, and I'm sure we're all happy help more where we can!   

[w3wilkes]

If you make that trip again, get off I-15 in Nephi Utah and head south to Levan Utah. That's a couple hundred more miles of US 89 and it's all fun!

[Richard McDonel]

ZUP,

Thank you!  You get post of the day - no, the post of the month - award!  

Yes, I pulled off the valve cover, and there was the eccentric, spinning free.  Should be problem solved, but I'm a little nervous about how it functions.  The bolt is large -  14 mm - but the manual only calls for 40 ft.lbs. of torque, as compared to 60 ft.lbs. for the skinnier head bolts. I did what the book said, and used  loc-tite.  But I look at the overall setup and it occurs to me that the natural friction of the pump lever on the eccentric would tend to loosen, rather than secure the bolt.   Anyone have any thoughts or experiences with that?

[Mark Maras]

 I've never had one come loose. Hopefully, a PO didn't tighten it properly. I'd tighten it properly and stow the tools needed to do a roadside repair in the car for a few months.

[Richard McDonel]

Follow up to my earlier post:

Again, my thanks to Zup Frosquisher (Come on, that's not your real name?  Is it?) for suggesting a loose cam / eccentric.   

The manual I reference in this case is the ubiquitous Haynes book, and it does indeed say that the cam-sprocket bolt should be torqued to 40 ft.lb, which is likely what I did back when I put the engine together.    Today I ran that by the local Guru of our faith, zKars (Jim), and he had not heard of such a thing.  You really heave on the wrench when tightening that one, he counselled.  When I told him where I got the 40 number, we checked other manuals (I don't have a factory engine manuals, but I do have two chassis manuals  if anyone is interested in a trade).   Chilton pretty much echoes Haynes, calling for 36 - 43 ft. lb, but Clymer came through with a more logical answer - 101 - 116 ft. lb.  So, it's now back on, torqued to 105, the pump is re-installed, and the engine runs, again with much thanks to Jim.  

So with the cam-sprocket cam now firmly in place, the risk I spoke about earlier, i.e., the potential loosening effect of the pump lever rubbing the eccentric the wrong way would seem to have been minimized, if not eliminated.  

I think we're going to be on the road this spring (spring comes late in central Alberta).