700 double pumper on a road car

Les Szabo · Post by **Les Szabo** » Tue Aug 19, 14 12:46 pm

MilesnMiles wrote:Can you just borrow a carb from somone local? has Mick got a simple 600vs knocking about. At least that way you could eliminate the carb before diving into the ignition etc..
I'm sure that carb is a wrong un.

Thats what I would do at this stage....the old PoE...perhaps another DP would be best to try.

Mick · Post by **Mick** » Tue Aug 19, 14 1:02 pm

There's not that many people round here who would have one. My 302 had a 600 vs on it but that's gone.
Mick

MilesnMiles · Post by **MilesnMiles** » Tue Aug 19, 14 6:00 pm

Blimey, that's a lot of cam!

Pete · Post by **Pete** » Tue Aug 19, 14 6:19 pm

MilesnMiles wrote:Blimey, that's a lot of cam!

Not a great amount of lift (no V-T-P clearance?) but it seems like a lot of duration.........maybe better off building a torque monster as opposed to mega-revs????

GJUK · Post by **GJUK** » Tue Aug 19, 14 6:31 pm

Hi Guys, thanks for your help. Will read your posts shortly once I've got things sorted at home today, just go back from work.

Just a note though, I'd like to get this engine running okay, not rip to bits and build another!!!

Jon

GJUK · Post by **GJUK** » Tue Aug 19, 14 8:46 pm

Out again tonight in the car.

Ran well driving around slowly only on primary circuit. Booted it through the gears and it was okay, quicky turned around and booted it again and it started to run rough... left it die, popped in in N and coasted to the side of the road.

pulled over took the hood off (90 seconds or so from the car cutting out)

And saw this car dripping fuel in...

It was not doing this when I had it in the garage earlier warming it up and only blipping the throttle a little...

Not normal is it?!

Pete · Post by **Pete** » Tue Aug 19, 14 8:48 pm

Fuel level or due to fluctuating fuel pressure, or worn carb........

GJUK · Post by **GJUK** » Tue Aug 19, 14 8:51 pm

Then to get the car started I left it for a few minutes. Had to start the car with the throttle pedal wide open.

Then while it was running this...

GJUK · Post by **GJUK** » Tue Aug 19, 14 8:53 pm

Pete wrote:Fuel level or due to fluctuating fuel pressure, or worn carb........

fuel level is correct.
fuel pressure was at just under 7psi when we checked

...worn carb.... Do I need to spend some more money?

Pete · Post by **Pete** » Tue Aug 19, 14 9:00 pm

Then there is clearly nothing wrong....

Do you have a fuel pressure gauge either external on the scuttle or an internal one via sealed capillary so that you know the fuel pressure is consistent?

Dirt from the tank can block a needle float valve and cause it to flood..........

GJUK · Post by **GJUK** » Tue Aug 19, 14 9:06 pm

Pete wrote:Then there is clearly nothing wrong....

I'm just stating what has been checked by myself and three others now. There is clearly something wrong; pinpointing it is proving to be quite difficult!

I do not have a constant fuel pressure reading, I will try and hook something up so that I can find out what happens when it being driven.

The carb has just been rebuilt everything was cleaned and it was doing this before the rebuild, though I can't dismiss the dirt theory I can't see it being the main cause after the clean/rebuild.

Would the dripping I videoed cause these issue, or perhaps its just a red herring?

Thank you.

Les Szabo · Post by **Les Szabo** » Tue Aug 19, 14 9:25 pm

try lowering your float level a touch, reduce pressure to 6psi....could also be a warped metering block, ruptured PV rubber diaphram, inspect, faulty main body gasket...etc.etc. Try the easy fixes first and then try another carb before you buy one...even Micks 1050 will do........I know you'll thank me for that Mick.

Mick · Post by **Mick** » Tue Aug 19, 14 9:37 pm

Jon
Try dropping the float levels a touch, take the carb off, open the secondary blades a little as per the video and back the idle screw off. There was only a weep of fuel from the sight plugs after i set them.
I would make a list of possible problems, check and tick them off as you do them, so you dont end up back tracking on yourself.
Did the motor start running rough when the fuel started dripping in ?

GJUK · Post by **GJUK** » Tue Aug 19, 14 9:45 pm

Les Szabo wrote:try lowering your float level a touch, reduce pressure to 6psi....could also be a warped metering block, ruptured PV rubber diaphram, inspect, faulty main body gasket...etc.etc. Try the easy fixes first and then try another carb before you buy one...even Micks 1050 will do........I know you'll thank me for that Mick.

Will try lowering the float level.
Maybe its a pressure issue, will try and hook up a gauge and regulator.

I have had a very kind offer of another carb being sent to me to try by dustymopar, just about to reply. Might be interesting to try one to see if it is that or not...

Thanks,

J

Mick · Post by **Mick** » Tue Aug 19, 14 10:01 pm

You dont really need any more than 5 psi on your car and the reading off your vac gauge was 7.
Fit a gauge and your fuel reg and drop it down a little, lower the floats but open the transfer slot on the secondaries and back the tickover screw down. Then try your vac gauge again and reset to max vac if necessary. Also check for wear on your timing gears. Did the guy who built the carb use carb cleaner and blow all the metering blocks through ?
I got to say, i wish we had the internet years ago, then it was all trial and error and talking to other people more knowledgable.
When i fitted my 440, it was all guess work, i took cardboard templates off someone elses elephant ears and cut my own out, then dropped it in and hoped it would run ok.
A few more tips here.