3 years of sitting... what to do first?

[Travel'n Man]

Have you tried just bypassing the regulator that is currently in line so see if that drops your psi down to the required level with your current fuel pump.........is there an inline fuel pressure gauge that you are getting a reading from?

[EverRude]

There is a guage inline between the regulator outlet and carbs inlet. One of those liquid filled dial guages. 0-15 psi I think. Anyways with the regulator failing the carbs can see full pump outlet pressure. The guage spiked to like 12 psi before I could shut it off. This is after I fiddled with it trying to adjust pressure down. BTW for that particular regulator. Down on pressure means up on adjustment screw. Not good to go the other way. Heh.

The pump is clearly far to high pressure to attempt using without a regulator.

In fact, having delt with this type pump before on my previous Z purchase I am fairly certain it is an injected Z pump that has been installed.

Here's a picture of the fuel pump that is installed.

Edited March 13, 2011 by EverRude
Added picture

[Carl Beck]

You can use high pressure pump - NO PROBLEM - - the Holly regulator is most likely FINE. The question is which springs are in that regulator. That regulator is available in either LOW or HIGH pressure versions - and the only difference is which relief springs you are using.

If the pump is putting 9 psi on its outlet - that's fine!! Fix the regulator!! The rebuild kits are about $15.00 as I recall. The kit contains both high and low pressure springs...

BTW - the pump pictures looks a lot like this

http://www.holley.com/12-802-1.asp

Note also that the above pump comes with pressure regulator 12-803 4.5 to 9 psi. Regulator 12-804 is 1 - 4 psi. They are the same body - just different relief springs.

See: http://www.holley.com/types/Fuel%20Pressure%20Regulators%20-%20Carbureted.asp

Don't waste your money buying a new pump - when the one you have is working. I've ran an electric pump on my 72 Z since 1975 and only had to replace it once in 35 years. Mechanical pumps fail just as often, and they don't keep the fuel lines pressurized.

FWIW,

Carl B

Edited March 13, 2011 by Carl Beck

[Carl Beck]

Post Pictures of your present fuel lines at the engine etc..

FWIW,

Carl B.

[EverRude]

Well I did get that new pump. Replaced lines and added prefilter to pump. Didn't need to do anything to restrict return line because that return is tiny. Too tiny IMO. Anyways I now have 3psi pressure at the carbs according to the inline guage.

The car started for a second then died. Subsequent attempts has it sputtering trying to start and one loud backfire at exhaust.

Any guesses? The distributer cap was corroded and well as rotor cap. Cleaned them up to see if there was any improvement. Nothing noticeable. Dont want to simply throw parts at it. Sure I'll be replacing those and the plugs (autolite 63's) soon but right now I suspect it's more than that. I noticed the number 6 plug wire has a cut in it. Seems intact but definitely cut through insulation. I've had cars run with far worse caps, plugs, wires...etc.

When starting one of these cars how long should the choke be on? Outside temp is around 65f now. Is it possible to flood the engine with too much gas buy using choke too long? Would that cause the backfire? Letting it sit now just in case. I'll try again in 30 min or so.

That other fuel pump was a holley. Was so dirty I couldnt read the label till I got it off and cleaned it. The new one is much much quieter anyways. Much prefer it. I'll keep the holley for potential future upgrades.

I'll post some pics in a bit. Meanwhile if you have anything I haven't thought of that would cause that sputtering attempt to start let me know please. Going to research that choke adjustment like Travel'n Man suggested. I may have it wrong and choke isn't coming off at all.

Here's some pics...

Edited March 13, 2011 by EverRude
added pics

[Zed Head]

Points or electronic ignition? Sounds like the car has a different engine in it than stock (electric fuel pump, etc).

[Powderkeg]

I you are interested I have a brand new set of NGK Blue Spark plug wires.

I would also recommend the NGK plugs over the Auto lite.

Looking forward to your progress.

Dave Ruiz

[Bruce Palmer]

Car has 4 screw round top SU carbs ,as it should, so is there anything I should do to prepare them before even attempting to start the car?

I would highly recommend you find a hard line fuel rail for your carbs and lose that loopy rubber line stuff. That's just a fire waiting to happen.

[Travel'n Man]

I would be nervous every time I closed the hood!!

Find a fuel rack - get in touch with Roger at THE Z BARN in Tenn. I'm sure he has dozens in his storage.

[EverRude]

I agree Bruce. Once it's idling more or less on it's own and I can hopefully drive her around the block, I'll eliminate alot of the jerry rigging that has been done to this car.

For an update. I did alot of searching. Seems the best thing to start with for tuning these cars is the valve lash. So I went through setting the intakes at .010 and exhaust at .012. Cold obviously since she wont run. Atleast 7 of the valves had no lash at all. None. Of the remaining ones maybe 2 were close.

So now with the valves set I decided to check for the main timing marks with the #1 at TDC. With #1 cam lobes making an upward "V" and both valves closed and the piston on the compression stroke I checked the rotor. It was somewhere around the #3 piston. Pulled the distributor and looked at the shaft. It's supposed to be pointed at around 11:25. It was more like 9:25. So I pulled the oil pump and repositioned the shaft a couple teeth to put it at 11:25.

Reassembled everything and tried to start her. She fired right up. Idled VERY roughly and required the choke and some pedal to stay running. Couple small backfires but she idled. I got out and tried to keep her running under the hood while looking things over and she died. Couldnt start her back up.

I assume someone has really screwed this thing up and now I am trying to fix all that just to get back to a point I can really troubleshoot the car an not PO's crappy work and neglected maintenance.

Going to set timing to zero on distributor but I am certain at this point new plugs, wires and cap/rotor would be helpful. They need replacing anyways so it wont hurt.

I'm sure I need to set points now as well. Just though of that just now actually. Shoulda check the gap and dwell after I set the disto shaft correctly.

Once I know I have solid spark at the right time and I can working with the carbs.

This has always been the worst and best part of working on old cars. Hope I live through it.

Oh and I broke a sway bar bolt trying to remove the bar so I could drop the oil pump. Now I have another fun job. Getting a broken rusty bolt out of a frame. Been a really great day.

[Bruce Palmer]

Character building...... they call it character building..... Skin hanging, blood dripping, character building....

[esmit208]

I you are interested I have a brand new set of NGK Blue Spark plug wires.

I would also recommend the NGK plugs over the Auto lite.

Looking forward to your progress.

Dave Ruiz

DITTO what Dave says......NGK wires and plugs and continue building character. We are sure you will turn out to be a proud Z owner.