Gas leak around inlet manifold

[brian-nz]

Hi All

I have a petrol leak which seems to be coming from the stud area on the back carb inlet manifold. It is hard to detect as the petrol is evaporating on the exhaust manifold. I notice that part of the inlet manifold may be missing - near the stud - where it rests on the ehaust manifold

It is a high port head and gaskets appear dry. I have taken the stud out and it is wet so I am assuming that the petrol is coming from this point.

Does the stud hole go right through the body of the inlet manifold causing petrol to seep through. It only occurs after engine is switched off

If I need a new manifold who are the best providers

 

Regards

Brian

[BlueTR3A-5EKT]

 

Is the rear carb is flooding?.  Have you checked the float levels of both crabs and the integrity of the floats to actually 'float'?

The stud does not go right through into the inlet track on the manifold I have.

[Ralph Whitaker]

Hi Brian,

just got my spare manifold out, and no the studs do not go right through. If there is a visible piece missing around the stud then it is fair to assume there is a crack in the manifold. Not big enough to affect the running of the engine, but enough to allow petrol seep out.

I think you will have to find a second hand manifold, I don`t think anyone will make a new one.

I found that the inlet and exhaust manifolds were not level on the head joint faces when bolted together, and slackened the 2 connecting studs & nuts to allow the manifolds to move slightly in relation to each other whilst attaching to the head. Maybe this was the case with yours and bolting up the manifolds to the head may have put them under stress which eventually failed. Also some mechanics do not realise that the 2 are bolted together and may have tried to remove the inlet on its own and caused the damage..

Ralph

[brian-nz]

Thanks Peter - I will check for flooding.

Ralph thank you for checking. With the weeping coming from around the stud area I suspect you may be right with perhaps a slight crack in the manifold. I have replaced the stud with a bolt and applied thread sealer to it to see if this is where the problem lies.

I see that Revington TR and Rimmers have second hand manifolds and have made enquiries as to condition.

I note that out Register had one last year so have made enquires there also. 

Regards

Brian

 

[brian-nz]

Hi All

Just an update. The inlet manifold has a crack along the base of the stud aperture. A second hand inlet manifold sourced locally and installed. The rear carb jet was slightly off centre so this sorted also. Once the weather improves a good run is on the cards. Thanks for everyones input

Brian