carbed Rover v8 not running well.

101v8 · Post by **101v8** » Mon Nov 26, 2007 11:32 pm

I have a 3.5L Rover v8 in a landrover, that is playing up. As you'll be able to tell, I'm a complete novice, so feel free to give seemingly obvious answers.

The last couple of times I've tried to start it, it starts the first time, and runs quite roughly for a couple of minutes, no matter what the choke is set at, or how much/little throttle its given. It then dies off, and will refuse to start, even if left for a long time. During the attempts to re-start it, fuel is often pumped out of the overflow pipes from the SU carbs.

During my recent rebuild, the fuel pump has been rewired to avoid the need for the 3 way oil pressure cut-off switch that was originally present, so it is pumping all the time the ignition is turned on (even before the engine has started). Is this what is causing the overfow, or is there likely to be a defect in the carbs?

I tested a few of the plug leads and was getting sparks at them. I took a spark plug out and had a look. it smelt of petrol, but didn't seem flooded, although i wouldn't know what to look for... (Its an electronic dizzy btw).

Any advice welcome, or links to relevant threads. I did do a few searches, but didn't come up with anything.

thanks for your help
william

ChrisJC · Post by **ChrisJC** » Tue Nov 27, 2007 8:21 am

Sounds like your floats are stuck open, as evidenced by the fuel spilling out of the overflows. Presumably if you leave the ignition on without cranking it then fuel spills over too?

Chris.

101v8 · Post by **101v8** » Tue Nov 27, 2007 9:26 am

The fuel does spill over with the ignition on without cranking too.
Is it a big job to fix stuck floats?

There is the odd time when it will fire up and run seemingly ok for 10 mins. Could it be the float sticking intermittently?

ChrisJC · Post by **ChrisJC** » Tue Nov 27, 2007 10:03 am

They be strombergs on the 101, not sure how you check the floats.

Also worth checking fuel pressure is 3-4psi. Too much and it doesn't matter how good the float valves are.

Chris.

101v8 · Post by **101v8** » Tue Nov 27, 2007 11:18 am

They've been changes to SUs in mine. hopefully that makes it easier.

the replacement fuel pump is one for the series III Stage I v8, so i don't think there'd be too much pressue. would there?

ChrisJC · Post by **ChrisJC** » Tue Nov 27, 2007 1:07 pm

If the carbs are the HIF design, then it's easy to get to the float mechanism. 'Just' take off the carbs, turn them upside down, take off the four screws and remove the bottom. Then if you remove the float, the valve will drop out of the valve body (the float stops it coming out normally).

You might need new seals though. Burlen Fuel Systems are a good place to start.

Not sure if the fuel pump is OK, probably is. But it's quite easy to check with a suitable gauge.

Chris.