It just wont run right

jonnyboy · Post by **jonnyboy** » Sun Aug 20, 2006 1:58 pm

I finally thought everything was ready for the MOT but the engine decided it didnt want to play.

I just cant get my engine to run well.

Every time I think its running right I go for a run and after half a mile it starts to pop and fart and loses all power. It seems to start backfiring through the carbs.

Heres what I have done:

I have checked the tinming marks corespond to TDC on cylinder 1 and set the timing with a strobe to 6 BTDC.

I have fitted new plugs, leads, rotor arm and cap with some better quality ones than the cheap crap that was on there.

I have balanced the carbs (strombergs) and adjusted the mixtures using the technique described http://www.gerull.nl/mg/technics/carb/carb_tuning.html

I went through it all this morning, backing the mixture adjustments right back and starting from scratch and initially it ran sweetly. It had a smooth idle and reved freely.when for a drive around the yard and it was all fine. Went for a run down the road and had to get towed home.

Any suggestions??????????????

Thanks

martin hughes · Post by **martin hughes** » Sun Aug 20, 2006 5:47 pm

Could it be fuel related?
Is the pump running ok?
Have you checked both fuel fillters?
Are the float chambers filling as required?

jonnyboy · Post by **jonnyboy** » Sun Aug 20, 2006 7:01 pm

The fuel filters were a bit clogged up and I think there may be some wear in the spindle shafts causing an air leak.

I have taken the carb's off and brough them home and am going to have a go at stripping them down.

martin hughes · Post by **martin hughes** » Sun Aug 20, 2006 8:06 pm

Good idea.
You can get the carb kits from craddocks, there are 2 types of kit one has more parts than the other althrough you will need both for a strip down of each carb, you will end up with some duplicated items for spares.
you will also need a steel ruler to set the float height.
Did you check the filtter in the base of the fuel pump?

mikeinbeverley · Post by **mikeinbeverley** » Sun Aug 20, 2006 8:32 pm

I finally binned my leaky Strombergs after unsuccessful re-builds & got a Webber. Together with a 1:283 rear diff I didn't think I was in the same vehicle! Accellerates effortlessly, makes the vehicle seem lighter. The power no longer fizzles out as the revs rise. I'm not kidding. I've had the "Truck" for past 20 yrs & done loads to it, but nothing has made a difference like this. But now I'm stuffed because its making water disappear at rate of 26m to the half-litre!! Just needs a new engine, that's all! That's Landrover life!

jonnyboy · Post by **jonnyboy** » Sun Aug 20, 2006 8:42 pm

Did you check the filtter in the base of the fuel pump?

Yep, that was full of gunk as well!

I finally binned my leaky Strombergs after unsuccessful re-builds & got a Webber

I plan to fit either a weber or a pair of SU's but need to get it running first for its MOT. Then I can bring it home as its currently on a mates farm near york and I am in Barnsley!

Might even get really silly and fit a megasqurit EFI system

I am already planning to get rid of the dizzy when I get it running.

I have stripped down one of the carbs tonight and there is a lot of play in the shaft so it looks like I will either have to rebush it or throw them away and find a cheap alternative.

martin hughes · Post by **martin hughes** » Mon Aug 21, 2006 5:59 am

I have seen brand new carbs on the web for £65 each

Post by db » Mon Aug 21, 2006 8:53 am

Although you're checking the carbs and have replaced most of the ignition bits
I wouldn't rule out the coil. I had similar problems on my Lightweight with a
coil which failed when it warmed up but was fine for the first mile or so.

David

jonnyboy · Post by **jonnyboy** » Mon Aug 21, 2006 10:07 am

I forgot to mention I replaced that as well

Got a large box full of nearly new pattern part ignition components in the garage!

jonnyboy · Post by **jonnyboy** » Mon Aug 21, 2006 3:07 pm

One suggestion I have had is to just run it on LPG and either just use the carbs as throttle bodies or get rid of them altogether and rig up some kind of dedicated throttlebody.

If I had the time and the money I might consider it as I want to fit LPG in the future.

foggydave · Post by **foggydave** » Tue Aug 22, 2006 4:38 am

Could it be the ballast resistor breaking down under temprature load.
This does give symptoms that appear to be ignition related.

To test just bypass the resistor for a short time to test but not too long.

jonnyboy · Post by **jonnyboy** » Tue Aug 22, 2006 11:29 am

Could it be the ballast resistor breaking down under temprature load

Not thought of that so will give it a try. It now gives me problems when cold so I am not sure if its temperature related.

I have been offered a pair of SU's from a discovery that I am hoping to pick up this weekend so will give them a try asap.

foggydave · Post by **foggydave** » Wed Aug 23, 2006 3:55 am

What ignition system are you using.
I use Lumenition electronic and had problems with cutting out when hot

I was told that Lumenition wires from the module to the dizzy especially the 3 pin connector hate getting hot so I re-routed them away from the heat and also shrouded them in a bit of washing machine tube and everything now seems ok
Also the module does not like getting hot either.

OR

This guy had fuel pump pressure problems ie pressure too high which gave the same symptoms as you are getting

http://www.v8register.net/subpages/V8NOTE328.htm

Hope this helps

jonnyboy · Post by **jonnyboy** » Wed Aug 23, 2006 8:47 am

Its currently running standard points ignition. Hadnt thought about the fuel pump, I would have thought that any excess presure would have been bleed off down the return feed to the tank though

Something else to investigate