reving problem

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cswagon
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reving problem

Post by cswagon »

Hello
I have just fitted a Range Rover 3.5 on Strombergs to my Landrover and have just started it for the first time yesterday.
On choke when it's cold it runs absolutely fine, and once it reached normal temperature I checked the timing and balanced the carbs and set the mixture by lifting the piston and adjusting through the top until no speed difference was heard.The tickover is not too bad now, but if I try to rev it at all it just drops down and cuts out.
I have noticed though, if I pull the choke out no more than an inch or so, it revs freely throughout the range.
Any ideas please before I start messing with my original settings.
Thankyou.
Graham.


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Post by Coops »

Hi and welcome,

sounds to me as if its too lean mate, and pulling the choke allows more fuel thus being able to rev again,
have you checked the CO out of the exhaust?
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cswagon
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Post by cswagon »

Hello and thanks for the welcome.
I don't have the means to check the c..o I'm afraid, but I will richen the mixture as you suggest and ignore the piston lifting method and see how it responds.
Many thanks and I'll let you know how I get on.
Graham.
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RoverP6B
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Post by RoverP6B »

I am not well versed on Zenith Stromberg carbs, but if they operate on the same principal as SU carbs, the needle profile is what governs the quantity of fuel delivered once off idle. Adjusting the mixture screws is only for setting the idle correctly.

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Post by CastleMGBV8 »

I believe the rubber diaphrams are prone to rotting, I would check these and replace if necessary. You might consider swapping the carbs for SU's which are far better, and can be got cheaply. If your not to far from Sidcup Kent I have a pair you can have

Kevin

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Post by V6GTE »

The rubber diaphrams do perish and would give exactly the problem you describe. Had this on my late Fathers Sd1 and the difference when the new rubbers were fitted was tremendous. They are only a few quid too.

There is an excellent book on the market (try Ebay) called SU Carburettors and fuel pumps. Its a blue book and gives details on rebuilding carbs etc and also suitable applications for aforementioned swops. Check out this link:

http://cgi.ebay.co.uk/SU-CARBURETTER-NE ... dZViewItem

Be aware that HIF Carbs are very problematic with sticking needle valves. Again easily rectified with a kit from someone like Burlen fuel systems.
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ChrisJC
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Post by ChrisJC »

V6GTE wrote: Be aware that HIF Carbs are very problematic with sticking needle valves. Again easily rectified with a kit from someone like Burlen fuel systems.
You mean the float bowl floods? Is there a fix for this as I believe I have this problem.

Chris.
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cswagon
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Post by cswagon »

Hello everyone
Many thanks for all the replies and kind offer of the S.U.s.
I do have a pair of S.U.s in the garage on a manifold which I'm considering putting on.
Are they a better bet than the Strombergs in all your opinions.
Thanks again.
Graham.
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ChrisJC
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Post by ChrisJC »

I have a feeling that Land Rover used Strombergs for so long because they will operate at a more extreme angle than SU's.

But I don't really know of any significant performance difference between them.

Chris.
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V6GTE
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Post by V6GTE »

ChrisJC you have a private message mate!

Cheers

Ian
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