Can anyone advise on this impeller issue please?

[Mike k]

I wnt to change the impeller this morning-only to discover that there just is not room to extract iof indert the new one. We are in a coffin berth here looking though an access point with the panel removed -it is is a wooden frame and i really dont want to start sawing into it as its upholstered on one side and forms part of a storage cupboards.

The picture shows the new one ready to go in and the totqal lack of space.

I am wondering if i can take the whole unit off ( its just 4 nuts compared to 6 screw s in the cover plate) but not sure if a long spline will prevent this or whether i would have to order special gasket or whether this is on the dry side of things. I really dont know whats best to do here

Can anyone advise if its ok to take the pump off given the space and whats involved or will have to be a carve up???


Any help really appreciated - the engine is a 4.2 Mercruiser 250hp D tronic.

Thanks Mike

 

[omega2]

looks like the pump will have to demounted, should be just about room to extract it, driven by a gear I would think, not "timed" so no forseeable problems.

 

[Spi D]

Seems safe to remove the whole unit.

Else you may have to lift the front end of the engine..

 

[volvopaul]

Yet another greatly designed boat, I see it all the time, as said try and unbolt the pump change the impeller and refit it, you may find the piece of bedroom will unscrew as the boats got to have had service before.

 

[Mike k]

Seems safe to remove the whole unit.

Else you may have to lift the front end of the engine..

Thats a really useful parts breakdown thanks

BUT will the spline mean i will need as much room to remove the pump housing off the spline ( all I have is about 2 inches?

 

[DAKA]

I also note you have a petty amount of rust on the viscous damper and pulley wheel.

Just guessing now but it could indicate a leaking pump seal which is another good reason for taking the pump off, its easy to change the seals (kit available from jabsco) .

run the engine at medium revs for a short while , turn it off and check the back of the pump for leaks. (leak looks like its been there for a season or two, but as the engine is hot , the water will evaporate going undetected.)

It is vital your viscous damper is kept in good order , it needs a quick scrub up and spray paint to protect.

 

[DAKA]

just an after thought.

its a key not a spine.

as soon as you remove it mark the position of the keyway on the side of the pump.

that way when you put it back on you can pre align it, or the impeller will make it difficult to turn to fit (extra long impeller).

 

[oldgit]

Blimming Heck.Who designed that !

Surely it has got be worth modifing the structure in front of the pump with some little panel or moulding that can be fixed neatly in position.
What the hell happens when your miles from anywhere,the pump impellor fails and youve go to get that engine going to get home wiithout assistance.

A choice between a call on CH 67 and an aesthetically pleasing cabin !

Its got to be changed every year and bet you a pound to a penny even the mere thought of the job may just delay or put the job off till later/forever ?

Get the saw out

 

[Latestarter1]

Yet another greatly designed boat, I see it all the time, as said try and unbolt the pump change the impeller and refit it, you may find the piece of bedroom will unscrew as the boats got to have had service before.

IF you have proper installation sign off this should not happen. Mr builder no engine sign off, therefore no engine warranty unless you fix the issue! All part of the reasoning behind creation of CMD, Mercruiser were **** at this stuff. Now all unravelled leaving Mercruiser to go back to their bad old ways, I feel sorry for new owners of new Mercruiser VW engines.

Even in properly signed off boats, seen motors sooo close to bulhead that it is impossible to get a puller in if fuel pump needs to come off, even fitting new belts is a challenge, never mind owners wife loves the galley work tops!

Happens, but nowhere as often in trucks. Two year old DAF truck with wrecked engine. Owner going beserk wanting to sue manufacturer, latent defect, etc etc. Took a look, engine full of debris, looks like air cleaner element?? Look at air cleaner...How does the lid come off, body builder put underrun bars right across the lid when fitting body to the new truck. Look at service records, SAYS filter has be changed as per shedule, did they crane the body off at every service? Filter was so choked that it had been sucked inside out eventually sucking two years worth of contaminated guts into the engine, nice.

Servicing dealer STILL screaming that they had changed the filter even when their insurance paid out.

 

[omega2]

Got to agree with Latestarter, some boat builders have no idea what they are on about, as Old Git says do your own mods and fell happy that anything you may need to "get at" are just that.

 

[oGaryo]

Surely it has got be worth modifing the structure in front of the pump with some little panel or moulding that can be fixed neatly in position.
What the hell happens when your miles from anywhere,the pump impellor fails and youve go to get that engine going to get home wiithout assistance.

A choice between a call on CH 67 and an aesthetically pleasing cabin !

Its got to be changed every year and bet you a pound to a penny even the mere thought of the job may just delay or put the job off till later/forever ?

Get the saw out

+1

 

[DAKA]

Hi Mike
Dont worry about taking the pump off, its easy .......

turn seacock off
Take the water hose off x2
undo 4 x nuts
pump is above oil level
just lifts out
mark the keyway position
stuff a BIG bag into the hole to keep spiders/fluff out but make sure it is big, you dont want it to drop in the hole.
there is an oring seal on the back of the pump to engine.



DIY skill level for taking the pump off is basic spark plug level.


Once you have removed your pump you will realize how easy it is and you will not bother to cut your boat up.

As to changing it at sea I suggest it is easier to inspect it twice a season while berthed and replace it at the first signs of wear which will reduce the chance of needing to change it at sea, but it can be done by removing the pump if you have to in fact I suspect it is easier on your boat with the great access you have from the cabin than on many boats where you have to crawl into a hot engine bay while pitching at sea .

once off you need a pair of circlip pliers and a jabsco seal kit and really I would add a bearing kit as you may have contaminated your front bearings with salt water.

then you take the circlip off and using nothing more than a vice you tap the bearings out the shaft(read up first as there is a grub screw to remove).

DIY for reconditioning pump a little higher but not much, its a about 1.5 hours quayside on a mooring bollard repair , in an emergency a sharpened bent wire coat hanger substitutes a circlip remover !
Should be quicker with workshop tools unless of course you are paying by the hour

If you are worried about your DIY skills then buy the marine kit and ask your local bearing workshop to fit them for you.
Marine kit is important as the spring seals need to be stainless.

A quick phone call to ASAP supplies will furnish you with the correct parts.

If you get stuck let me know as I carry a spare kit but its on my boat and Im at home so cant get you the part number.

Of course there will be no need to change the seals if it isnt leaking.

at the back of the pump, where it is narrow there are 2-4 square holes, i suspect water will be leaking from these holes.

Even if you dont have a leak I really cant impress upon you enough the importance of keeping your damper in good order.

You could buy a reconditioned pump(one went on ebay recently for £50) for a quick change and then recondition your own, that way if you need to change an impeller at sea you would exchange the pump which is almost certainly quicker than 7 out of 10 impeller changes as they tend to be a wrestle even with a puller.

cheers
Pete

 

[Mike k]

Hi Mike
Dont worry about taking the pump off, its easy .......

turn seacock off
Take the water hose off x2
undo 4 x nuts
pump is above oil level
just lifts out
mark the keyway position
stuff a BIG bag into the hole to keep spiders/fluff out but make sure it is big, you dont want it to drop in the hole.
there is an oring seal on the back of the pump to engine.



DIY skill level for taking the pump off is basic spark plug level.


Once you have removed your pump you will realize how easy it is and you will not bother to cut your boat up.

As to changing it at sea I suggest it is easier to inspect it twice a season while berthed and replace it at the first signs of wear which will reduce the chance of needing to change it at sea, but it can be done by removing the pump if you have to in fact I suspect it is easier on your boat with the great access you have from the cabin than on many boats where you have to crawl into a hot engine bay while pitching at sea .

once off you need a pair of circlip pliers and a jabsco seal kit and really I would add a bearing kit as you may have contaminated your front bearings with salt water.

then you take the circlip off and using nothing more than a vice you tap the bearings out the shaft(read up first as there is a grub screw to remove).

DIY for reconditioning pump a little higher but not much, its a about 1.5 hours quayside on a mooring bollard repair , in an emergency a sharpened bent wire coat hanger substitutes a circlip remover !
Should be quicker with workshop tools unless of course you are paying by the hour

If you are worried about your DIY skills then buy the marine kit and ask your local bearing workshop to fit them for you.
Marine kit is important as the spring seals need to be stainless.

A quick phone call to ASAP supplies will furnish you with the correct parts.

If you get stuck let me know as I carry a spare kit but its on my boat and Im at home so cant get you the part number.

Of course there will be no need to change the seals if it isnt leaking.

at the back of the pump, where it is narrow there are 2-4 square holes, i suspect water will be leaking from these holes.

Even if you dont have a leak I really cant impress upon you enough the importance of keeping your damper in good order.

You could buy a reconditioned pump(one went on ebay recently for £50) for a quick change and then recondition your own, that way if you need to change an impeller at sea you would exchange the pump which is almost certainly quicker than 7 out of 10 impeller changes as they tend to be a wrestle even with a puller.

cheers
Pete

Thanks very much Pete i really appreciate that information. I have emailed ASAP but not sure if its a Jabsco or not.

As usual this site is just fantastic and any and all replies are greatly appreciated .Mike

 

[Spi D]

I'd say it's a Jabsco 29700-1331

 

[DAKA]

I'd say it's a Jabsco 29700-1331

its jabsco without a doubt and I reckon you have it spi d , well done

just need mike to confirm the number on the impeller as the photo is upside down ? 17018- ???

now the last bit also concerns me because it looks like a nitrile impeller which is arguably unsuitable and I would use neoprene 17018-001 but the photo is too blurred and I could well be wrong.

is it hard or soft mike, ?
is the end dead flat or does it have embossed circles on each vane ?

 

[Spi D]

Jabsco Impeller 17018-0001 P. is a Neoprene Impeller, 8 Blades, Brass Insert.

Replaced Jabsco 17018-0001.
Replaces CAT 3N5895.
Replaces Volvo 3583602.

 

[Mike k]

its jabsco without a doubt and I reckon you have it spi d , well done

just need mike to confirm the number on the impeller as the photo is upside down ? 17018- ???

now the last bit also concerns me because it looks like a nitrile impeller which is arguably unsuitable and I would use neoprene 17018-001 but the photo is too blurred and I could well be wrong.

is it hard or soft mike, ?
is the end dead flat or does it have embossed circles on each vane ?

Hi Peter

the impeller was bought as genuine mercruiser part number 816814T-£98.35 plus vat so i hope its the right one. Its fairly rigid but can bend the splines reasonably easily its certianly not floppy/Soft at all. The impellor is on boat but going tommorrow so am going to bring it home and can check the number them. I think the end is flat. Look forward to reply.

 

[DAKA]

Hi Peter

the impeller was bought as genuine mercruiser part number 816814T-£98.35 plus vat so i hope its the right one. Its fairly rigid but can bend the splines reasonably easily its certianly not floppy/Soft at all. The impellor is on boat but going tommorrow so am going to bring it home and can check the number them. I think the end is flat. Look forward to reply.

if the sides are flat like it has been cut with a sharp saw/knife then its most likely nitrile.

it is harder than neoprene and is really intended for fuel .

it is a sod to fit and a sod to take out.

it has a memory in that as it is hot it will mould to your housing, when it cools it will go ridged and the blades will crack as soon as you turn the engine over next time it is a cold engine.
if you dont change it after 5 months you run the risk of blade bits going into your cooling.

take it back and get the jabsco one designed for pumping salt water cost about £58.

If you get any hassle I should be able to find an email from jabsco confirming the pumps they provide to boat engine manufacturers should all leave the factory with neoprene ( I know they dont and some nitrile ones end up in boats).

 

[DAKA]

spot the difference


1) 29 hours

2) 2 seasons and ready to go back in !

 

[superheat6k]

Pump access

Looks like a simply awful installation - presumably it has never been changed.

Despite the ease of removing the pump, access to the impellor is a safety concern, unless you have two engines, so I would make the mods to the structure, or check out just how easy removing and re-installing it actually is.

If it is as easy as described by earlier posters and the pump will actuallly come out without moving the engine then fine, in which case I would invest in a complete spare pump (fit the new and carry the old with a new Jabsco impellor as a spare).

I would also carry some spare mount bolts, as dropping these in the bilge in a rolling sea could prevent even a straightforward swap.

Also I note the pipes are single clipped. If you are close to or below the waterline I would double clip.