SLROC Forum

I took my stage 1 V8 for an MOT yesterday passed with only one issue, they had to put fuel in it because it ran out during the emissions test. I thought this was a quite odd as i had filled it up the night before.

So I pick it up from Doune motors and top up just to make sure and head on back to callander. Just as I'm leaving Doune I get a sudden loss of power, doesn't cut out, just wont go anywhere. I pull in wait a few minutes and drive on with out problem... for a couple hundred meter, then the same thing happens again.

After a very long stop start jouney I get back to callander and get the fuel filter off thinking I'm not getting enough flow. Turns out theres a fair amount of water in there, a very curious situation as it's a brand new tank only fitted a couple months ago when I replaced the rear cross member. Filter back on I take it for a run and the same thing happens again. After a bit of head scratching and attempted carb tuning I take it for another few runs and it does a little better but still the loss of power seemingly at random so I gave up for the evening

This morning I take off the breather linking the two halves of the fuel tank thinking it could be blocked causing a vacum in one side. doen't seem to be, blowing in one side gets air out the other. I enrich the mixture and take it for a spin, no problems so I get confident thinking it might've just been a bit lean. I head off to Gartmore and get there with out any problems, pick up a friend, head in to stirling and everything is running smoothly. Just as I'm happy with my new/old truck it happens again...

To cut an already long story short... after a bit of rest it's fine untill I over heat up by the David Stirling monument then once topped up with water fine till the other Side of thornhill when it looses power again. Eventually back in gartmore we trailered it back to Callander.

Fuel filter again removed, this time just full of crud, bypassed the filter to see if that helped. It didn't.

Fuel pump is an aftermarket diaphragm pump that seems to be alright, thought one of the terminals could be shaking lose but after securing it a bit better the same problem still persisted.

So, anyone every had a similar problem? or any idea what could be causing it?

Jack

Hi,
sorry there is a lot going on in the story with fuel tank etc.

Is or was there are Breather pipe problem with the replacement tank and an air lock.

RE,
'overheating' at David Stirling monument & topping up.

? Have you got a cylinder head gasket gone, or have you not got the system bleed properly, airlock at the thermostat housing or something?
Are you using a correct ratio or Anti freeze/summer coolant in the system?

Good luck with it and hope you get it all sorted out.
george

if you have had water in the filter theres probably some right through into the carbs as well, theres maybe another filter in the connection onto the carb as well like a small metal gauze.  i think at least you will need the top off the carb for a look , and i am sure you can buy an additive to help treat water in the fuel. you probably got the fuel from the petrol station with water in it the way the rain has been.

if it is a v8 on strombergs     it could the bi metalic spring that holds a valve shut on the side of the carb     this opens with heat and lets air in after the venturi       i did away with them      but on reflection it was only one that caused the bother   when realy hot under the bonnot sugesting it was  to hot although it never boiled up   clean fuel first then carbs      but with mine it was intermitent and unpredictable     new carbs just did the same

Having had similar ish problems recently I would remove the carbs and check there is nothing blocking the needle valves and there is nothing in the float chambers which shouldn't be there.

Air leaks?

Oil in both dashpots?

Is there fuel overflowing out the pipes on top of the carbs?

Both carbs set to the same mixture?

Is the fuel pump always running? Which type is it? I am guessing when you say "terminals" that its not the Facet type as that has one positive lead and is earthed through the body.

Thanks for the replies.

There didn't seem to be any problem with the breather pipe and I don't think my head gasket is gone but haven't really invesigated yet, it'll be on my list of things to do today.

Water in the carbs sounds entirely possible so that'll be getting checked too.

As far as the bi mettalic strip goes, I don't have them, the entire temp compensator assembly isn't there on either carb. Could that be the problem?

Definately oil in both pots, no fuel overflowing, mixture is the same or should be very close.

Fuel pump is always running, I'll double check and get back to you on the type but you are correct in that it is not a facet pump earthed through the body as it's a complete plastic housing.

As for air leaks, I'm not sure. Where should I be checking?

Jack

Air leaks mainly after the carb, so between the carb and manifold, manifold to head etc. Any split vacuum hoses?

WD40 sprayed round suspect areas with the engine running will indicate a leak if the engine speeds up briefly.

Fuel pump is an Ecco 1LM12 http://www.fuelflow.co.nz/FF_cms_03/eshop?page=shop.product_details&product_id=65&flypage=flypage.tpl&pop=0 2-3 PSI 1L/min... I remember reading somewhere I need 3-4.5 PSI (does that sound about right?) so a new pump will be ordered. Any suggestions?

Jack

Its for an engine nearly half the size, and as you say the pressure may not be enough to keep 2 carbs fed.

I've just bought this one to replace the same model on my RRC. The existing one has lasted 6.5 years and 45000 miles, most of them under strain as the pump runs when on LPG regardless. It still works fine just got sticky the other day and I don't want it to fail on me!

Carbs have come off and had a bit of a clean, there was a small amount of water in each of them and the filters on the valve were a bit manky so ordering a couple of new ones.

What pump is it you're using?

Sorry I never posted the link earlier!

http://www.rimmerbros.co.uk/Item--i-PRC3901P

Cheers, has been ordered along with filter and new valves, gaskets and such for the carbs.

hi jack
had same sort of  problem a couple of times , you dont say if its a lwb or a swb but on lwb one more thing to check is the rubber pipe that connects fuel filler to tank , if it has a hole or split or loose water off rear wheel is sprayed onto pipe and runs into tank, i would take top off tank and have a look inside if its got water in it chances are thats where its coming from. hope this helps shug... 

It's a lwb, rubber hose between filler and tank is new but I'll double check I've tightened up the clips properly.

Is it sorted?
Drew.