Engine Will Only Run On The Choke

Post by **KeithB** » 29 Jul 2004 10:31 pm

Replacing the carburettor on the 1.7 is a simple task, but Mikes has only done 22,000 miles so would seem a bit premature, any car owner would be p***ed off if the carburettor only lasted that long! There are a lot of reasons as to why the car is behaving in such a manner, if it turns out to be the carburettor then cleaning it should sort the problem, the Haynes manual details how to dismantle it, but try a blast of air from a compressor to blow out the jets and retry the engine. This has occurred on a few ocassions with my own, but I have only replaced the carburettor once at the 120,000 mile stage when it wouldn't work at all. Dirt can get into the petrol and make its way into the float chamber, as well as the petrol filters that came with the car I have also fitted an in-line filter, I have also sawn a centimeter off the end of the fuel pipe in the petrol tank to prevent it sucking up rust and dirt. So before going to the expense of a new carburettor the original is repairable with a bit of patience.

Post by **foggyjames** » 29 Jul 2004 10:45 pm

True, its low mileage, but its also quite old...and all that hot/cold cycling on short journeys is worse for it than endless motorway miles.

cheers

James

Post by **KeithB** » 29 Jul 2004 10:54 pm

I agree totally, but if the carburettor isn't warped, there is no air leak, the fuel is arriving OK etc., etc., and the only conclusion is an internal problem then I'd have thought dismantling, repairing if needed and cleaning would be the first thing to do, if the carburettor then proves incurable replace it with a new one. Then make sure it gets a good run every week along a fast stretch of road! All within the "law" of course!

Post by **5lab** » 29 Jul 2004 11:04 pm

you can get stuff to spray down your carb that cleans the insides. saves taking it to bits

Post by **foggyjames** » 29 Jul 2004 11:45 pm

Well yes, that's why you use the WD40 to detect any air leaks....before you even go to the trouble of dismantling. Carbs are a PITA sometimes

cheers

James

Post by **5lab** » 30 Jul 2004 07:54 am

not wd40 - special 'carb spray' - its the best thing ever at getting greasy cr*p off stuff. just spray it in and ya get a performance boost

Post by **petavius** » 02 Aug 2004 09:40 pm

I've had this problem, as soon as you hit low revs it cuts out, my problem was the carb, it was knackered!

Post by **shimon340** » 05 Aug 2004 12:20 pm

My 1.4 340 also every so often will cut out as the revs fall ( i,e, after coming off the motorway ). Also, sometimes it feels sluggish around the 2000-3000 rpm range. This problem is intermittant and usually occurs after I have run the car very low on petrol. My conclusion is that is it dirt in the fuel blocking the fuel lines or the fuel jets of the carb. I have an inline filter after the pump but would like to fit second one on the tank pick up - there is one there from original but it prob needs replacing or supplemented. I'd go with the suggestions of the people above and clean out the carb.

1.7 carbs.....

Known problem about warping the base plate. Volvo was only aware of this too late. The 400 series have a modified plate with a cooling pipe running round it - air I think.. to stop the base from warping.

S

Post by **wjp01908** » 05 Aug 2004 09:02 pm

The b17 and b14 engine have problematic carbs but for different reasons - as some have noted the base of the solex(?) carb fitted to the b17 is prone to warping.

There are number of remedies of varying efficacy: machining, thick gaskets, gunge etc.

I have heard (but never tried it) that you can dress the base flat if it is not too bad, by using some fine grinding paste on a thick sheet of glass, or very fine wet and dry (used wet) on something like a piece of kitchen work top. May be worth a try as a last ditch attempt. Just make sure you clean every last bit of abrasive off before refitting.

The Weber on the b14 mostly seems to shake itself to bits - I have yet to see a rough running one that didn`t have the whole top loose. I also had a close shave myself when a bung fell out of the carb flooding the entire, hot engine bay with fuel while driving along the motorway. That was the fastest I ever got the family out of the car.

It`s now part of my regular servicing to go over the carb and nip everything up

I have found the idle solenoids on these to be a bit dodgy - if your car was a 1.4 that would have been my choice if it only ran on choke

Will

Post by **5lab** » 06 Aug 2004 12:16 am

my b14 carb was shaken to bits - so bad that all of the screw threads had pulled thru. new one solved most of my problems in one, quick go thou

Post by **petavius** » 06 Aug 2004 12:50 am

same as mine!

Post by **special** » 06 Aug 2004 12:59 am

i had exactly the same problem with my carb mine is webber all i did was spray carb cleaner into the carb its ran fine ever since when spraying rev car to stop it cutting out
when you have finished spraying rev the car to 3000rpm and hold for 30-60 seconds dont use wd40

Post by **Duvel78** » 06 Aug 2004 01:11 am

special wrote: all i did was spray carb cleaner into the carb its ran fine ever since when spraying rev car to stop it cutting out

Which spray do you use? Someone knows a good product name?

Post by **special** » 06 Aug 2004 01:21 am

any type realy its widely available over here i think stp do one and so does wynns I use a cleaning product called borothyne from work we use it to clean vinyl worrying thing about borothyne is it melts plastic

but at least it gets rid of carbon. You could always try redex but you get a lot of white smoke for an hour or two makes a handy smoke screen

Post by **5lab** » 06 Aug 2004 08:29 am

i use the wynns stuff. the thing you have to be careful about is that on some old cars the only thing holding the engine together is the carbon in the first place