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MG TD TF 1500 - Main bearing crankshaft position

Hello,
Before reassembly my crankshaft, I have a question regarding the main bearing. In fact, I don't remember the position of the main bearing in the block. Can you confirm with picture that is the good one ? Is that the groove must be shifted like this ?
Many Thanks in advance.
Didier

Roussel Didier

Other picture

Roussel Didier

Roussel - it does not look as though the bearing grooves are lined up, as they should be. Be sure the bearing oil holes line up with the cap and block holes, with the bearing nicks in the right place, and you will be fine. Do be sure you have the cap in the right direction, or else the engine will bind. I mark the caps before I pull the engine down, if they have not been marked before (nothing from the factory).

Tom Lange
MGT Repair
t lange

Thank you Tom for answer. About bearing oil holes, it is impossible for me to do a mistake because on cap and block there is a keyed.
If I fit the back cap (not possible error due to its shape), the groove is not lined up so I think the 2 other bearing are the same assembly.
Picture of the back cap.

Roussel Didier

An other picture of the back cap.

Roussel Didier

Picture of the center cap

Roussel Didier

Roussel,

On my engine the digits on the cap faced the front of the engine, just like your picture, so the orientation of the caps looks good if I compare it with my engine. I don't know if all caps were fitted that way, so no guarantees given!

I do agree with Tom that the bearing grooves should line up.

Willem van der Veer

Am I right to suggest " the first line" from Toms remark is not solved yet. ( block oil holes to the bearings ? )

respectfully,

Gerard
Gerard Hengeveld

Hi Didier,
The oil grooves in the bearings I fitted to the mains, also did not line up, as your first picture shows. However, the oil holes all lined up as well as the bearing locating tabs. I believe this is the way they should be installed.

George
George Raham [TD4224]

Rousel..
I would look closely at the shadows on the ears of the bearing castings. The shadows should match the outline of the cylinder block. Look carefully and you will see the difference in shadow outline.They realy are different
Sandy
DARNOC31

Looking at the first photo above :-
The grove in the bottom shell seems to be cut off center.
However the grove in the upper shell looks to be centered? How can these groves ever match up? - But no matter how you fit them - the oiling holes in the block must match the holes in the shell.

You would think the grove would be in the same position on both shells.

Do you have a photo of just a shells set placed side by side?

Maybe an offset grove is done to give more assess to the shaft surface for oiling?? I would also think that a centers position would give more even oiling to the journal - regardless.

It has been too long since I was in there...

Rod.
R D Jones

Hi, the oil groove should NOT be in line, there is a lead in to line up with the groove on the opposing shell.Look at the rear cap which will only go on one way and you will see the alignment.If the grooves were in line you would have an unwiped area of journal.It is imperative that they are correctly fitted a because they match only the engine they were machined in.
I have worked on an engine that was put together wrong and would not even crank,it was so tight(I didn't assemble it,I just took it on !)
Ray TF 2884
Ray Lee

Ray, I like your explanation about the 'unwiped area'. Never thought about that.

I hope I don't have unwiped areas on my journals, but I'm not going to look!
Willem van der Veer

Didier,
If you are still not sure about your caps.
assemble the cap without the bearing shell, with your finger nail check the joint. The correct way round, you will not feel the joint, the wrong way round you will.
Machining was not as accurate then as it is now and it shows in these fits.
Ray TF 2884
Ray Lee

Thank you everybody for your answer. I just found the old bearings and during disassembly, I noted their position by painting an arrow indicating the direction of assembly. And the conclusion is that the assembly is the same you can see on the pictures. I don't know what to think too much ... In addition, there is only one way to get the bearings on their support
Other question : Why the groove is greater at the ends of the bearings ?
Roussel Didier

<<Why the groove is greater at the ends of the bearings>>

I would think that is to create a path for the oil to flow to the other groove that is not in line with it. If it was not greater, a constriction would occur that would limit the oilflow?
Willem van der Veer

This thread was discussed between 28/09/2013 and 05/10/2013

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