Page 1 of 1

Viva HC 1972 Cutting out

PostPosted: Mon Apr 22, 2019 5:59 pm
by Viva Man
Hello

My Vauxhall Viva HC, keeps cutting out after about 30mins driving. When it first happened I cleaned the fuel pump and cleaned the carburettor. I found small sandy grains which was cleared out. It was assembled and run well but again after about 45mins it started cutting out, it would tick over but every time a put on the accelerator it cut out. the only way I got home was to keep opening the choke to give extra fuel. but after some time it was nip and tuck how I got home and had to use the choke to get into the garage. After the first time I added a fuel filter and could tell the fuel filter was virtually empty.

This is so frustrating as it runs well to start off with then feels like starvation of fuel. I have read it could be the tappets not set right. But i'm open to anything at the moment.
The fuel pump is old but seems to pull through ok.

Has anyone got any tips to help me?


Thanks

Re: Viva HC 1972 Cutting out

PostPosted: Mon Apr 22, 2019 6:39 pm
by droopsnoot
What type of carburettor is it fitted with? If it's a Stromberg, have you checked the diaphragm is good on it? You really need to stretch it a bit to check, even a tiny pinhole can cause poor running.

Re: Viva HC 1972 Cutting out

PostPosted: Mon Apr 22, 2019 6:47 pm
by 1972nail
There is a common problem related to this symptom. Loose inlet manifold. The manifold and the bolts warm up and release the pressure on the metal gasket. This allows air in and weak running. Check the manifold bolts are tight. Depending on your carb, there may be a bolt inside the manifold to check as well.

Re: Viva HC 1972 Cutting out

PostPosted: Tue Apr 23, 2019 8:42 am
by lord13
I had a similar problem, mine kept cutting out and needing full choke after about 30 mins of driving.... I never got to the bottom of the fault as the engine was cooking up constantly, I had a mind that the fuel was evaporating because of the intense heat, but dismissed that as it would run on choke and had to get the fuel from somewhere right?
The loose manifold weakening the mixture seems a better idea, i'd try that, run up to temp then tighten the manifold bolts, can't hurt. :)

Re: Viva HC 1972 Cutting out

PostPosted: Tue Apr 23, 2019 2:38 pm
by Kraken
Mine hasn’t my been cutting out but has been running lumpy. I believe air was getting into the fuel lines. Tightening up the inline fuel filter seems to have cured it, and now the filter fills up a lot more than it did beforehand.

Re: Viva HC 1972 Cutting out

PostPosted: Sat May 04, 2019 9:58 pm
by Viva Man
Thanks Everyone, good advice never thought of the manifold.

The carburettor is a Zenith.

Re: Viva HC 1972 Cutting out

PostPosted: Fri May 17, 2019 3:45 pm
by Viva Man
Hi All,

Just to advise I think I found the problem, the accelerator shaft into the carb has broken and its completely come out, I have never seen this before.

Re: Viva HC 1972 Cutting out

PostPosted: Fri May 17, 2019 5:20 pm
by 1972nail
Too heavy on the right foot? :lol:

Re: Viva HC 1972 Cutting out

PostPosted: Tue Jun 25, 2019 12:06 pm
by Viva Man
Hello,

Well I think I have just found this issue.

When I bought the Viva I put on new manifold beather hose from rocker cover to airfilter and air inlet in the carb spacer to inlet manifold using Zenith 301z carb. I have got to the stage where I tried everything apart from dancing in clogs.
So my last chance was to replace the inlet manifold gasket. But as I took of the rocker cover manifold breather pipe it come apart, Well it actually fell apart. This was new over a year ago when the issues started. I have pictures but they are too big to add. I replaced with the old one and it seems ok but will give it a proper run when the weather improves. It shows you cant trust new parts. I didn't check it because it was new.


Hope this is the end of the story.