[nutcase]

After poor Naranto's 99T knocked some teeth off not only his water pump shaft but also his jackshaft, I started getting a little more worried about my pump which was seeping a little

So I decided to break out my water pump tool and have a bash at taking the pump out of mine to 1) examine the condition and 2) rebuild it with new seals and bearing if all was otherwise ok.

The pump in mine has obviously been at least looked at in the past as there was copious amounts of orange sealant round the cap. I don't know if the pump itself has ever been removed in its 80,000 mile life.

Anyway. Onto the job. This is based on a fuel injected 1977- car. Earlier cars have a slightly different arrangement for the pump, and carb cars have different bits in the way!

First thing to do is to make the pump accessible. Disconnect the battery then remove the alternator. The alternator bracket also bolts to the pump cap, so that needs to be moved. Earlier cars have to have the engine lifted to clear one of the bolts, fortunately, mine had a slotted hole so it just swung out the way. Drain the coolant from the block. For some reason the manual says to drain it from the radiator, but that leaves the block almost full!

Then the inlet manifold needs moving. Examine all the bits and pieces hanging off it and decide the best way of clearing the area. In the end I took the manifold and throttle body right off as the gasket to the head needed removing anyway. Be VERY careful with fuel injection pipes as they are brittle!

Once you have the pump cap clear, remove the three screws and work the cap off:

One manky pump. I decided to clean the area up while the pump was still fitted so that it was easier to remove any gasket debris before it fell into the depths of the engine:

Delicate bit number one time. Fit the pump tool to the block and screw the central shaft down whilst threading it onto the pump shaft. Make sure it is on as far as it will go to spread the load on the weak iron thread. It's left handed so turn the pump tool the right way!

 

[nutcase]

Check that the pump is free to move in it's skew gear, then gently but firmly raise the pump shaft using the tool. When the shaft is free, unbolt the tool from the block and carefully remove the it with the pump still attached, making sure you don't hit the pump on anything. This should leave a hole in the block:

And the pump and tool together:

Delicate bit number two: Dismantling the pump. If the impellor falls off, then some or all the pump major components will need replacing - it is supposed to be a press fit. I found a large socket that was deep enough to contain the pump whilst supporting the impellor, and using a wide vice as a press, removed the shaft from the impellor. I then stripped the remaining components from the shaft:

 

[nutcase]

Check the components for reusability. The bearing, oil seal and water seal should be discarded and replaced as a matter of course. I consider myself very lucky as the shaft and impellor had no significant signs of wear or damage. The new bearing I used has slightly more balls in it than the original. I don't know if that will help for the future, but the original bearing did have a lot of play compared to the new one (which is already of a slightly increased clearance than a standard bearing of those dimensions):

Assemble the new bearing onto the shaft (the original had the etched markings on the lower side of the bearing, so I put the new bearing in the same orientation. I don't know if that is a must or not). Fit the circlip (I used a new one although it isn't strictly neccessary). Then it's tricky bit number three. The shaft/bearing assembly needs to be pressed into the block. Make sure the bore is scrupulously clean, then offer the assembly up, making sure the gear starts to mesh with the jackshaft.

Using a suitable sized sleeve that ONLY touches the outer race of the bearing, use the pump tool to push the bearing into its bore until it is fully home. It's not easy to judge that point, but gently tightening the pump tool does give good "feel" for when it hits home:

Smear the sealing lip of the new oil seal with oil, and offer that up to the shaft. Using the same sleeve and a mallet, hammer the seal home:

 

[nutcase]

For the water seal, the OEM ones are rubber but the one I have is stainless steel. So I smeared some hydraulic sealant round the case to be on the safe side. Probably overkill, but I don't want to have to pull it all apart again in a hurry!

Then using a sleeve larger than that used to fit the bearing and oil seal, and again using the tool, press the water seal home:

This particular sleeve actually came with the pump tool.

 

[nutcase]

The impellor will have a groove worn at the contact point with the water seal:

This needs removing. I used a very flat surface, wrapped some emery paper over it and spent about half an hour taking the raised surface away to leave a reasonably flat area throughout. I then used some Autosol metal polish to get it a little better, then thoroughly cleaned the impellor including the bore. Be careful not to remove any material from the bore though else it could work loose in operation.

The impellor then needs pressing onto the pump shaft. Use the pump tool again, with another suitable sleeve that contacts only the impellor and not the shaft protuding through. Be very gentle with it, I found it didn't need a lot of force to press it on, and the manual reccomends releasing the pressure every 1/4 turn and reapplying. As soon as the impellor bottoms out on the shaft release the tool and remove it:

 

[heavy_t]

Blimey, I think Boxman knows a bit about the water pump on my previous 99 :cheesy:

 

[nutcase]

Almost finished

The pump should look pretty much like this when it is fully installed:

Don't worry too much about the offset look to the impellor - the hole is drilled centrally - but the casting is fairly uneven.

Then all that is left to do is thoroughly clean all traces of old gasket from the pump cap, and fit it with a new gasket. Also repair any damage to the underside of the cap with chemical metal or similar and sand to the correct profile. Again, I was lucky and my pump cap is in pretty good condition. Curiously the manuals don't state a torque for the cap - but Haynes say 22lb/ft.

All that then remains is to refit everything removed to clear the pump, tighten anything that was loosened, refill and bleed the cooling system, connect the battery and start the engine. Don't be suprised if there is a little water leakage for a while until the new water seal beds in against the impellor. Allow at least 4 or 5 hours driving.

I'm not up to that stage yet as I've taken the opportunity to clean up my inlet manifold somewhat.

Ok. What have I missed? Any tips to add? Any questions?!

Oh, I do apologise for teh terrible photo's. My poor camera really doesn't like closeups! I have got a new one now, but I'm NOT pulling the pump apart again just to take more pics :lol:

 

[Tomarse]

Nice one, and well timed! My pump tool should be arriving in the next few days and then i plan to try it!

 

[sonett1]

Great article and very well done!

The only thing i did that was different was to heat up the impeller before i pressed it onto the shaft, it just expands the hole in the impeller slightly and makes pressing it on so much safer and easier.

 

[nutcase]

Tomarse, part of me doing a very long winded version was becuase I'd seen you had a tool on order. I used 4 "adapters" with the tool to do the job - only one came with it the rest I had to make.

Sonett1, thanks A good idea with heating the impellor. However, it didn't take great deal of force to fit the impellor so I don't think it is strictly necessary - but anything to take some of the risk out the job!

Added one bit to the first post - drain the coolant Also added torque figure for the pump cap.

 

[Naranto]

Excellent report Richard. A+.

My 99T is now on the road again, sporting a good second-hand jackshaft and new pump. it also needed a little bit of welding to a suspension arm for the MOT, but other than that :roll: - it passed.

 

[nutcase]

Great news

 

[Raven18940]

Holy moly . Hope I never have to do this on my car.

 

[nutcase]

The B engine water pump really is the weak link. Special tools, severely limited access, high risk of damage to engine internals etc.

Hence the guide so people can see exactly what's in store for doing one. Not impossible by any stretch, but long winded and you have to take things carefully.

I've almost finished putting the manifold back on and reconnecting anything, so soon I'll be able to say if it works or not :lol:

 

[Tomarse]

I've just tried to print some of this out to take outside.. next time you do a walkthrough like this, make the pictures a tad smaller so that it is printable!

Theyre also a bit big and table breaking, even at 1024x768!

My engine is now partially stripped. Water pump is the next thing to remove, then its the idler shaft and then the crank/pistons. I was looking at the water pump last night.. It seems like a wierd design how there is that gap from the side through which you can see the seal!

 

[nutcase]

The pics are a bit big, aren't they ;oops: I'm no expert with photoshop, and if I tried to make them any smaller they just got more and more blurred

The hole you mention is the "leak hole". Allows you to see when the water seal (or less likely, the oil seal) is letting go.

 

[Tomarse]

The free microsoft image resizer here is a nice simple way to resize photos.

I think things are easier to read with smaller pics (640x480 or 800x600). If you need a higher res one then link it.

I only noticed it was hard to see as i tried to print it, and today im using a different pc with a lower res than mine at home and the text is all off the edge of the page.

Over all the sites i work at now, i probably have getting on for 1000 PC's, and probably 90% of them still only go at 800x600 resolution...

 

[Tomarse]

My pump is now out. I had a lot of trouble getting the cap off as it was very corroded into place, and very well sealed! (It didnt have any bolts in - it was just held in place by being well stuck!)
I spent a good 30 minutes working round it gradually with a screwdriver and then progressivly sized chisels. I still managed to crack it though :evil:
I dont know how i would have coped doing this job with the engine in the car!. it was hard enough with it on the ground and seperate from the gearbox.

You should add a warning about this to the writeup! - Cap is fragile!

Its very corroded inside though, so i dont think its that much of a loss. I will have to use my other cover (which is hopefully better), or try and source a replacement.

I suppose i should start putting this back in my own thread now!

 

[nutcase]

I really have been lucky with my engine havn't I?! Well, not 100% lucky. See other thread

 

[nutcase]

Images resized to 800 pixels wide.