Marina 1300cc Exhaust Manifold

[FranklinLeicester]

I have got a manifold leak which I think at worst may be a crack in the casting,there is evidence of a previous weld. If it comes to replacement, are there any others that are identical - Mini, MG Midget, Allegro etc? Or does it have to be only the Marina item?

[daniels917]

Re: Marina 1300cc Exhaust Manifold

Hi Franklin, as far as I can remember most of the mini manifolds were cast as one piece with the inlet and exhaust, and the exhaust was set at a bit of an angle, the metro was similar but had a duel outlet in many cases. some Midgets had tubular manifolds, others were similar to the marina, but all were twin carb. What about using a tubular manifold from a mini (1275) and cut and weld the two into one section to fit in the Marlin. Best of luck Merv

[FranklinLeicester]

Re: Marina 1300cc Exhaust Manifold

Thanks for that info Merv which confirms my memories and research on Ebay into this. You're idea of taking the opportunity to upgrade the manifold is sound, there is a 1275 tubular one on offer which I may go for, it is the basic 3 branch,1 piece manifild which would not require cutting and welding, only the mating-up job to fit it to my down pipe.

[dogoncrazy]

Re: Marina 1300cc Exhaust Manifold

Franklin
Later Marina and ital 1300 had twin outlet pipes as opposed to the single outlet, Mini Allegro and Midget are to the best of my knowledge all different. I had one of the earlier ones crack at the bellmouth and being cast are virtually impossible to weld with success.Asd Merv says the only alternative is a cut and shut job on one of the tubular systems though in my case I found a replacement through the Marina owners cub spares guy. I did have a spare twin outlet type but that went I think to Lee when I disposed of all my spare Roadster bits

[ggrum]

Re: Marina 1300cc Exhaust Manifold

I have a spare 'A' series unmodified cast iron inlet/exhaust manifold in my garage that I keep tripping over if anyone is interested.

[FranklinLeicester]

Re: Marina 1300cc Exhaust Manifold

Hi Geoff, May I take you up on your offer? Please Email me to arrange details fdwandmpw(at)talktalk.net thanks, FRanklin.

[FranklinLeicester]

Re: Marina 1300cc Exhaust Manifold

Having spoken to Geoff, it seems that my set-up may not be standard Marina 1300. Mine has separate exhaust and inlet manifolds. The manual shows the inlet and exhaust to be combined, which is what Geoff has on offer. Mine has the casting number 12G 3538. Research on the forum archive shows this number to have cropped up in 2006 in a discussion between 2 chaps in Scotland. So, is mine a later Marina manifold perhaps? Any advice greatly appreciated.

[stevejgreen]

Re: Marina 1300cc Exhaust Manifold

Not sure if this will help as my experience with 1300 engines is minimal but...
On my 1800TC the exhaust/inlet manifold is a combined unit. The alloy inlet manifold is bolted to the cast exhaust manifold.
But on other 1800 B series like the MGB I have never seen this combined manifold.
The picture of the complete engine is a TC marina and you can clearly see the upstand connection between the exhaust down pipes. The exhaust manifold pictured alone is MGB

I have never got to the bottom of this but assume it might be an attempt at achieving quicker warm up of the carbs or some mechanical support but the difference between Marina and MGB manifolds is a little odd as I would have thought that a cooler inlet manifold would be preferable.

[stevejgreen]

Re: Marina 1300cc Exhaust Manifold

Franklin, I have posted some valuable info regarding your manifold on the fastmarina forum. I think the manifold you need is available on Ebay.

[FranklinLeicester]

Re: Marina 1300cc Exhaust Manifold

Thanks for the info Steve and as you may have seen I've responded to your research at the fastmarina forum. (Is that a contradiction - fast Marina?) For the benefit of other interested parties, the plot thickens. The part number I need,12G 3538 is listed in Mini circles as being a combined manifold whereas mine is 2 separate units.

[dogoncrazy]

Re: Marina 1300cc Exhaust Manifold

Franklin
I'm afraid the part numbers are not familair only because i never made a note of them. However in my case I removed by careful hacksawing and grinding the inlet from the exhaust and substituted a MG metro inlet manifold as per David Vizard's bible on the 'A' series. You can then choose whether you wish to have the inlet heated by the water or not and it gets rid of the 'hot spot' which can lead to fuel vaporisation.

[stevejgreen]

Re: Marina 1300cc Exhaust Manifold

I think that Alan has hit the nail on the head. I recon someone must have been out with an angle grinder.
Its lodged somewhere in the background of my mind that this was a suggested mod.
Difficult to see when the vital part id concealed under an inlet manifold and carburettor assy.

[FranklinLeicester]

Re: Marina 1300cc Exhaust Manifold

Yes, this idea is backed up by somebody on the Marina forum too. I have done a tempory job gagging the crack with filler and will follow it up with Gun-gum or similar if needs be till I can get a "new" one sourced. The inlet manifold has 4 bolt holes for the carb but my carb only utilises 2 diagonal opposite ones.

[lil_red_roadster]

Re: Marina 1300cc Exhaust Manifold

Sounds like an 1.5" HS4/HIF38 carb on a manifold designed for 1.75" HS6/HIF44 carbs...the 1.5" carbs (& 1.25") only ever used a 2-bolt fixing...the larger 1.75/2" used a 4-bolt fixing...iirc. So go on, fit the larger carb...you know it makes sense..!

[donsayers]

Re: Marina 1300cc Exhaust Manifold

The other very good inlet manifold is the one off the 1.3 Maestro, this was a long horse shoe shape with the carb mounted on the inside towards the engine. The length gave excellent torque at low revs. I think it had an electrically heated "Hot spot" for starting in cold weather.