1275 Marina engine crank seal conversion

[MMT1968]

Hi there,

I have installed a 1275cc Marina engine to my Traveller and due to a badly worn as to say destroyed rear scroll seal I have mounted an ESM-crank seal kit for 1275/Ital engines. But even if mounted correctly to specs it is almost impossible to have it sealing well. This kit to my opinion has got one main problem. The 3 allen head screws that hold the upper half of the seal housing together with the triangular piece to the block need to pass by the crankshaft flange. Therefore there are 3 recesses in the inner surface of the seal housing that are impossible to seal correctly. Even if the seal is glued in with motor silicone and these recesses filled securely with that stuff after some time another leakage occurs.
Now here comes my question.
Does anyone have mounted a crank seal kit for the 1275cc Midget engine from MiniMania in USA to a 1275 Marina engine? https://www.minimania.com/part/RIC777/C ... World-wide

This kit comes as it looks from pictures and tutorial video without those recesses in the inner wall of the seal casing and thus should prevent these leakages. But Minimania cannot say if it will fit as 1275 Marina engines have never made it to the USA. They only know the Marina with B-series engine.
To my opinion it should fit as the measures of crank and block are the same in Marina and Midget as long as the 1275 engine is concerned. But does anyone know exactly if it does or not?

Thanks for any reply
Chris

[philthehill]

https://www.morrisminorspares.com/engin ... ly-p830198
Throw away what you have and fit the MED rear main seal kit. That works.
https://www.med-engineering.co.uk/colle ... n-seal-kit
There is a You Tube video you can see what it is about.
https://www.youtube.com/watch?v=9sxy1pUq83Y&t=46s
I have experience of the ESM type kit and there were two main problems.
1. The seal is expected to run on the outer face of the flywheel mount flange. That face is not a machined face so if the face is not perfect it shreds the seal.
2. To fit the kit a spacer is required between the flywheel and the rear of the crankshaft. In my experience that spacer is not hard enough and can allow the flywheel to come loose. That is what happened to my engine when I fitted the kit. I had to buy a new crankshaft and went back to the original set up.
I would advise that you speak to MED before purchasing the kit to ensure that you have what you require.
Phil

[MMT1968]

I have seen that seal kit from MED and it looked good to me but it need some machining that I don’t have access to. That’s why I looked at the kit of Minimania.
To solve the problem with the surface of the crankshaft flange I mounted a Speedy Sleeve that provides a perfect surface and increases the diameter of the flange a bit and thus rises the pressure on the lip of the seal.
The ESM kit‘s problem are the recesses in the seal housing. These are not present in the kit for a 1098cc nor in the kit of Minimania. That’s why I was asking.

Chris

[philthehill]

I never had a problem with the sealing of the spacer or any other parts requiring sealing except for those problems quoted above.
I fitted the kit at least 20 plus years ago now and I do not recollect any recesses - can you please post some photos of the recesses and the other parts.
The use of a Speedy Seal is the way to go.
As regard the American version of the kit I cannot help you there but it looks similar to the kit you have just fitted.
It is listed as suitable for 1275cc Midgets and Sprites. Be aware that the rear of the 1275cc Midgets and Sprite crankshaft is different to the Marina/Ital.

[MMT1968]

Here comes a foto showing these recesses.

[philthehill]

Thank you for posting the photo.
Having those recesses is not good. They were not in the kit I fitted. No wonder you are getting oil leaks.
I have blown up the photo of the American kit and that does not have the three recesses in either the seal carrier outer face or the recesses on the centre angular face.

[MMT1968]

That‘s what I see also. On the website there is a tutorial video. In that video they show the installation of the kit on a 1275 midget engine which crankshaft has 6 screw holes. To me it looks like the same as my Marina engine so I guess that kit could fit.

Chris

[philthehill]

Note my comment above in that the rear of the Midget and Marina crankshafts are different.

Marina crankshaft 1.jpg (52.96 KiB) Viewed 2949 times

[MMT1968]

Well, my crankshaft looked a bit different before I have let it polished. The scroll is hardly visible. But where does the MED Seal run on? It surely can’t run on the scroll part and next to the flange is not enough room.

[philthehill]

I have never seen a scroll worn that bad!!
That is why I suggested that you speak with MED before purchasing a seal kit.
The machining required may be to grind a surface for the seal lip to rub against.
What is the rear main bearing cap like?

[MMT1968]

The bearing cap looked relatively well and has been machined also when the main bearings were rebored but the horseshoe piece was so badly worn that I decided not to machine it as well and install the crank seal conversion kit instead. That’s why I guess there is no alternative to that. So I have to solve the sealing problem anyway.

Chris

[philthehill]

In that case all I can suggest is that you fill the recesses with plastic metal and machine to bring back to correct format.
or
fill the recesses with plastic metal, fit the seal wiped with Vaseline , let the plastic metal harden, remove the seal by splitting the seal holder and then fit the seal kit as per instructions.
You may have to do some work around fitting but I suggest that it is doable and worth a try.
JB Weld has some good feedback on this forum.
Phil

[MMT1968]

Thanks a lot. I already thought about a similar solution.
I bought some Loctite 3090 which is fast hardening heat resistant Epoxy to fill up these recesses after the seal ist inserted. JB Weld is a good alternative butif I fill the recesses to machine them afterwards the allen head screws can not be inserted as there is not enough room for the head to pass. So the filling must be done when the housing is mounted and the seal at its place. Loctite 3090 is a quick hardening Epoxi with an open time of around a minute so all must be handeled quick but precisely.

I will have to get the engine out again as I will change the gearbox to a 5-speed. At that time I will do that job of closing these recesses. Actually the seal is inserted with motorsilicone and the recesses carfully filled with that stuff also. When my vacuum system to put negative pressure to the crank case is working already I hope that this minimizes the leakages at the rear crank seal also.

Chris