Volvo Penta MD series rubber drive coupling

[mogmog2]

Came to put the gearbox back & found a piece of the internal rubber drive coupling lying in the engine. Initially peeved, but now relieved. The forecast and tides this weekend aren't great, so a few days delay won't matter.

It appears that this is held on by a mildly chunky bolt and that may well be all. Unfortunately, the neither (my versions of) the Engine service manual, or that of the Mono Shift gearbox actually cover this...

Has anyone taken one of these off? It looks like it is just the one bolt - ie unbolt & fit a replacement coupling, or any unexpected (expensive) parts that need to be replaced as part of the process? Or even just a push fit?
Many thanks



PS
Any idea if these are just rubber, or do they have a skeleton? Just wondering about polyurethane....what sort of temperature it would experience?

 

[mogmog2]

I know it's not quite the same, but even so...

 

[scottie]

If the rubber has deteriorated then that needs to be replaced but the two steel couplings do not require to be touched at all however if the rubber has been damaged by oil then the oil leak causing the problem also requires attention
Was there any sign of oil inbetween the the two casings

The spider is only rubber although quite substantial and no dismantling is possible

 

[scottie]

MD in Volvo speak only denotes a Marine Diesel which could include up to 12ltr units and covers a very large number of engines

 

[VicS]

MD in Volvo speak only denotes a Marine Diesel which could include up to 12ltr units and covers a very large number of engines

The OP has an MD2B with an MS gearbox

 

[scottie]

The OP has an MD2B with an MS gearbox

to be or not to be

You obviously pay more attention to detail than me

 

[mogmog2]

MD in Volvo speak only denotes a Marine Diesel which could include up to 12ltr units and covers a very large number of engines

Yes, although I didn't consider the extent of the full range, I didn't want to limit this to the MD2B as I know that others in the series use it. Obviously though a 12l engine isn't going to have this coupling lol.
Thanks for the confirmation on removing the thing.

however if the rubber has been damaged by oil then the oil leak causing the problem also requires attention
Was there any sign of oil inbetween the the two casings

I can't tell if this has been oil hardened. I assumed it had hardened with age and environment. 90% of the engine oil poured out when I separated the gearbox and you can actually see into the engine's innards, so no obvious oil sealing to leak.

I was asking about the skeleton as I was contemplating the feasibility of pouring my own from polyurethane. If it had a skeleton, I would need it & could assuredly get it out. That it hasn't is good news though.
My main concern with polyurethane is the operating temperature it would experience.

 

[mogmog2]

to be or not to be

You obviously pay more attention to detail than me

VicS has contributed to my several posts on this saga so knows.

FWIW, I tried to lever it off & it wasn't happy (too much rocking). Reached in and pinched the hub and it slid off with ease.
Furthermore, a Gentleman on Facebook has come up with a replacement at a very agreeable cost, so I should be back in track sometime next week.
Thanks everyone