75ZT Community

A pal of mine has an MG ZS180...same mileage as my 190 give or take a few hundred.....an apparently well looked after piece of kit, complete with oil catch tank.....but sadly non-working VIS (Variable Intake System) motors...Anyway, thanks to the good offices of Mr Stocktake this was to be rectified...

However....the VIS 'rods' turned out to be very flappy and very noisy when we had swapped the VIS motors over.....lots of wear in evidence...my feeling is that her catch tank was a bit too successful and had left the linkages in the manifold too dry....hence she has a knackered manifold whilst mine is still lovely and quiet....and yet her VIS still failed? So, catch tank or no catch tank?

Hmmmm, something not right with that one Zeb, The VIS motors you returned had both been tampered with previous, one was rebuilt with the cam in 180 deg out and had never worked since, the other was what looked like just some old bits that had been put in to fill the spaces up, total scrap. So, it may be the manifold was also messed about with.

People ask me often how long a Vis will last? It's allways difficult to say how long as you are never sure what enviroment it has to work in. If an engine does not "breathe" well it may have more oil than is healthy for the vis and kill the motor really quite quickly. But, that may assist the butterflies. Other end is very little oil ingress giving a VIS a long and healthy life but as you say that may not be good for the linkages. Shame we have no data on the subject .

Oooer Dave....still feel a bit bad about this! Hopefully there will be some more defunct VIS motors in the offing shortly! I do wonder if running on LPG (Liquified Petroleum Gas) and hence having 'cleaner' oil with less carbon, means that, whilst there may be oil in the manifold, it is not so detrimental to either the manifold or the VIS? That said, I am on my second refurbed VIS power motor....although the balance motor is original?

As per PM, Carl, it's not a problem .
Your last VIS power valve was a relay that failed, I don't think that was due to oil but who knows? It was nice to be able to see how one of the previously refurbed ones had faired. I only use solder that contains as nuch lead as I can buy in it (currently 40% lead) this gives the joints a little more strength in holding things in place as opposed to the lead free stuff. It would appead that the 40% lead in the solder does give mechanical strength to the joint as these were undamaged.

LPG. i would imagine that is another unknown to add to the miserable life of the inlet manifold

After replacing two noisy inlet manifolds previously I have now gone down the catch tray route.
First one was failed while sticking to the 12 month service schedule by a main dealer.
Second one after changing to 6 monthly oil changes by me.
Drained a fair bit of brown oily gunk out of the catch tray after a few months of use.