Volvo MD7A - Water Pump

[Decrepit_Mariner]

Help!

My Volvo MD7A is leaking past the spindle on the raw water cooling pump.

At vast expense, I've bought the service kit. This comes without instructions.

Before I disappear into the locker armed only with spanner and intuition can anyone advise/has access to a manual?

 

[nightjar]

If you bought a service kit from Volvo then I suggest next time you speak to Cleghorn Waring who will supply you with the parts at prices well below our "friends" at Volvo. Don't know what the service kit contains but inspect the main drive shaft carefully as any grit that was trapped by the seal can wear a grove in the shaft; no option other than to replace the shaft which Volvo wanted £97 + VAT for on its own. Cleghorn Waring supplied new shaft, seals and bearings for less. Nearly all the sea water pumps for Volvos are Jabsco and Cleghorn can supply the bits ex stock.

 

[tome]

I also have a MD7A and manual, there isn't that much information other than routine stuff. I replaced the impellor and had a bit of a job undoing one of the four cover screws. I didn't need to bleed it afterwards (there's a small bleed screw on the housing) but lightly grease the impellor blades before re-assembly and make sure you rotate it in the direcction it will run as you re-insert the impellor. Volvo don't use any sealing compounds on the gasket, and this worked fine for me.

Remove the pump complete for overhaul rather than try to do it in situ as it's all quite fiddly.

What's in the service kit? The one I buy only has only the impellor and paper gasket for the front cover. If it's leaking past the shaft then the seal has probably gone, hopefully this hasn't damaged the housing.

Good luck

 

[kgi]

first remove the exhaust pipe and the water cooled elbow swing those out of the way (13mmx4 bolts) now you get a good look at what you are doing. remove the spring clip holding the water pipes onease the tension on the two bolts on the pipe coming from the gearbox, carefully pushdown on the pipe until it comes clear of the pump undo the two clamping bolts on the pump body and gently rotate it to free the top pipe.. pullit clear. personally i remove the exhaust manifold and the injector lines as it helps me on my particular boat .. the seals are fairly easy to extract remember the flat part of the seals face inwards, dont forget to put the phosphor bronze bush in first, i copiously coat mine in copper slip on the inside, when you put the shaft in lubricate it first and push it in gently with a rotating motion, reassemble everything remembering to put new seals on the water pipes where they enter the pump otherwise you will have all kinds of problems with water flow( normally works great at idle and to about 1500 rpm after that the water flow breaks down)... a thirteen mm spanner and socket, slotted screwdriver, some tea and a sense of humour will get the job done keith@fareal.batelnet.bs

 

[Decrepit_Mariner]

The kit includes:

cover with bolts

spindle

two seals

brass? bush

brass bracket (clamp) with screw - haven't a clue where that one goes until I get to the boat!

 

[Decrepit_Mariner]

Thank you for the detailed and helpful reply.

I don't have the engine in front of me! Your description allows me to visualise the process pretty well.

Could you please clear up the following queries which now arise?

- is it correct that the impeller is basically driven by the spindle which simply slots into the engine?

- can the pump simply be detached from the engine once the pipes have been disconnected and the clamping bolts are undone?

- the bush goes where - into the pump body or the engine?

- what seals are on the water pipes - this I didn't anticipate!

- any particular torque settings?

- can you recommend anything (is it required) to seal the exhaust bend to the manifold?

Regards

 

[kgi]

further to your post, the impeller fits into the fork end of the spindle, there are two bolts holding the pump on with small shaped clamps. the bush fits between the two lipseals in the pump. how tight?... 1 white knuckle for the pump bolts, remember you will have to do this again so not to enthusiastic on the spanner, 2white knuckles for the manifold bolts, ihave never sealed my joints on the manifold and they have never leaked, oh and remember to put copperslip on the threads of all the bolts, next time will be a doddle..... keith fareal@batelnet.bs

 

[Jcorstorphine]

Make sure when you are fitting the two shaft seals that the second one is not pushed in too far as it will cover the small drain hole on the casting. The function of the drain hole is to let any water that seeps past the water seal to drain away. When I purchased my previous yacht which had a Volvo MD2B, the previous owner or his mechanic had fitted the seals incorrectly with the result that the when the water seal wore, raw seawater was pumped into the engine as the oil seal will not prevent water passing. The reason being that the oil seal is fitted back to back with the water seal. The Volvo manual does not mention this.

PS some volvo engines use Johnson water pumps

 

[cats]

Hi Nightjar,
Do you have a phone number or location for Cleghorn Waring please?

 

[scottie]

Re: Water Pump bleed screw?

on most Jabsco type pumps
there is a screw which holds the cam in place if this is removed and the pump move the cam is likelly to be displaced and as the impeller being depressed by the cam is the main reason the pump works it would best left alone!!!!!