Leaking carb

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Tups93
Posts: 17
Joined: Tue Aug 02, 2016 2:37 pm

Leaking carb

Post by Tups93 »

Evening all,

Well I took the plunge and sold my disco so I can keep the stage 1 and I'm working my way through a list of small jobs, one of the jobs is my leaking carb. I've seen I can buy a carb overhaul kit but I've never worked on carbs before and I'm looking for some pointers and advise before I start.

Cheers
map1275
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Location: Brisbane, Australia

Re: Leaking carb

Post by map1275 »

Where's it leaking?
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Geoff
Posts: 599
Joined: Sat Oct 29, 2011 2:21 am
Location: Leicester UK

Re: Leaking carb

Post by Geoff »

What's it leaking? Oil or petrol? My carbs still need topping up with oil regularly even after being rebuilt. I think it's one of the enduring mysteries of Stage 1 ownership where that oil keeps disappearing to. Anyone know?
2 1981 Stage One 109 V8 SWs
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Lewy
Posts: 77
Joined: Sat Jul 16, 2016 1:22 pm

Re: Leaking carb

Post by Lewy »

I ran my 110 for 4 years without any oil in the dashpots.

It really didn't make any difference.

As for rebuilding them, it's a pretty easy straight forward job.
Tups93
Posts: 17
Joined: Tue Aug 02, 2016 2:37 pm

Re: Leaking carb

Post by Tups93 »

Looks and smells like petrol and appears to be leaking from the big square gasket at the bottom.
map1275
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Joined: Mon Jul 21, 2008 2:48 am
Location: Brisbane, Australia

Re: Leaking carb

Post by map1275 »

If it's just the gasket then it's extremely straightforward though painful due to access of some mounting bolts. You could get away with just a gasket or the minor repair kit.
Some minor seepage (stains) in this area is not unusual but being wet needs fixing. Unbolt as little as possible, turn upside down on the car and remove the screws...

A major rebuild is complex when it comes to reassembling the linkages and repairing shaft wear. If you are in England then Burlen's rebuild service is quite affordable with a better than most finish.
Tups93
Posts: 17
Joined: Tue Aug 02, 2016 2:37 pm

Re: Leaking carb

Post by Tups93 »

So carb unbolts as a whole unit?
map1275
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Joined: Mon Jul 21, 2008 2:48 am
Location: Brisbane, Australia

Re: Leaking carb

Post by map1275 »

Yes, four 5/16 UNF nuts as per your manual.
disco2hse
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Location: Auckland NZ

Re: Leaking carb

Post by disco2hse »

Geoff wrote:What's it leaking? Oil or petrol? My carbs still need topping up with oil regularly even after being rebuilt. I think it's one of the enduring mysteries of Stage 1 ownership where that oil keeps disappearing to. Anyone know?
You're on Strommies, right? The oil eats through the rubber of the diaphragm, then seeps through it at an increasing rate until you replace the diaphragm. 3-in-1 oil is the norm, then I started using higher viscosity oil when it got too bad. Repeat as necessary. Or replace with SU's.
Alan

1983 ex-army FFR 109 Stage 1
2005 Disco 2 HSE TD5
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Geoff
Posts: 599
Joined: Sat Oct 29, 2011 2:21 am
Location: Leicester UK

Re: Leaking carb

Post by Geoff »

Yes, Strombergs - I was a bit disappointed to find I seemed to be topping up after fitting new diaphragms just as much as before. I don't like the sound of the oil eating through my diaphragms. I use 20W/50, same as for the engine and LT95, as per that very valuable manual. I've seen special oil for carb dampers online (at a price) - any difference? My other truck's got SUs - so where does the oil go in them? What do you call 'too bad'?
2 1981 Stage One 109 V8 SWs
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disco2hse
Posts: 1637
Joined: Sun Apr 27, 2008 3:51 am
Location: Auckland NZ

Re: Leaking carb

Post by disco2hse »

They do consume some around the seal. The only real difference that using a lighter grade of oil will make is to improve your accelerator responsiveness. However, engine oils contain compounds that will break down the rubber of the diaphragm sooner than purely mineral oil like 3-in-1. Too bad was having to fill every thousand k's or so (which sometimes is every two weeks). I was replacing the diaphragms pretty much every year, which got tiresome.

I wonder if, when the oil heats up, it loses viscosity and leaks around the edges? There is quite a lot of pressure in there too.
Alan

1983 ex-army FFR 109 Stage 1
2005 Disco 2 HSE TD5
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