Gday...Ive got a Nissan A14 engine in my Morris 1000 sedan... after fuel tank I have an inline fuel filter then a elec pump then fuel hose to the copper (?) fuel line to the front of car...then another inline fuel filter...then a another electric pump then a pressure regulator then straight to the standard Hitachi Carb...
heres the prob....which also happened on my last Morris a ute with an A12..
When at higher revs the engine has a tendency to sometimes loose power and choke a bit. Then it dies down the revs before finally cutting out....
You can imagine how shirty this gets me when trying to keep up with busy traffic on the motorway.
What can it be? it did it with the first pump...i replaced it....
still did it.....added second in engine bay...still did it....
added pressure regulator...still doin it...

rebuilt carby...still doin it...
noticed vacumn advance was a loose fit...still doin it...!!! AAARRRGHHH

HELP!!!
Is it common or heard of when in the original cars? if so what causes it???

If not a prob in original Im thinkin it may have somethin to do with the metal fuel pipe from back of car to the front....as it would have been suited to the 998cc oringinal engine???
should I change it for a thicker internal diam. one??

Please help....

please answer here or to my email
on
tartfarmer@hotmail.com[email]

tartfarmer@hotmail.com[/email]

the line could be a problem i run braided hoses which i cant rember the size of but im running twin 40s so its a bit different. what psi are the pumps? and very important, what size is/ are the needles, you could have the wrong sized ones which will not be able to give your engine the fuel it needs. im not sure where you can get this info from but some one will know the optimal sizes and pressures etc for a a14.
good luck.
Quinn

It certainly does sound like fuel starvation. A question though....why are you using 2 fuel pumps and 2 in line fuel filters? One of each should be more than adequate as long as the pump has reasonable capacity. Electric fuel pumps normally work better as a "pusher" rather than a "sucker". It is better therefore to mount the fuel pump down low and close to the fuel tank to minimise the length of suction. The filter is best mounted in the pressure side of the fuel pump (between the pump and the carb). Old morries have a small diameter fuel line as standard and they are also suseptable to getting squashed. I would replace the original fuel line with a new bigger line (at least 5/16 or 8mm). Make sure the fuel tank breather is not blocked. If you can, mount a tee joint at or close to the carb and fit a fuel pressure gauge in the line. That way you can tell whether you are getting a fuel starvation problem before the carb. If the pressure remains constant without dropping off at full revs then the fuel pump, filter and line are ok. If the engine still appears to starve at full revs with good fuel pressure then you need to look at the needle valve area. Fuel pressure in the area of 3-6psi should be adequate with a standard carb.

I hope this helps :)

Sounds like a restricted line. You may need to look at the size of your pickup in the tank or for a squashed line, and check your float level. If still no go, GO BIGGER for sure.

Hi Simon

I had a similar problem once - dirty (rusty) fuel tank.
Remove the fuel filter closest to the tank, place it in a vice and cut it open (dont try and view it through the clear filter casing, you will not see enough). If it is full of fine settlement, you've found your problem. You can put new pumps and filters in but the minute you start the engine, dirty fuel in the tank will clog and restrict the filter again, thus fuel will flow at low revs (small demand) but at high revs, the filter acts as a restricter. If this is the case, simply remove the tank and flush it out the best you can.
Hopefully this might be your problem (cheap fix)

Micko

If you do find that it is rust in the tank you can do the old hotrodder trick-
Take out the tank, put a chain say 1 metre long inside the tank ( but first tie some rope or wire to the chain so you can get it back out!) then jump up and down and basically make plenty of noise with the tank so that you brake loose most of the rust. ( Just screaming and making noise doesn't work!)
Then flush the tank out and there is a fuel tank sealer you can buy, it's like a 2pack paint ( but fuel proof) Poor the stuff in and do another dance and then you will get another 10 years out of your tank!