water pump - do they fail?

[HJ2]

It's an Airtex from RA.... But anything is possible

[Steve A]

If your existing pump has only done 500 kilometres I would do a "feel" comparison with the new one, they should feel roughly the same.
If your existing one fits ok and the new one doesn't then use that with a new gasket.
There's not much to go wrong with a water pump other than being worn and or corroded (seized up).

[HJ2]

Nope, It's not worn, but it leaked over the gasket, so probably my own fault.
I'll try cutting the seal to a better fit for the new one first and keep you posted. I keep the current one as spare because indeed there's nothing wrong with it.

I had a real hard time fiddling the engine support out this time as well! Tinkering on the M100 still feels a little voodoo-like sometimes

[CalElan]

Honestly, I know the received wisdom is to replace the pump when you do the belts and I get that..but, although I had a pump in-hand the car had only done 60k. The water coming out was very clean, the pump turned over smoothly by hand and showed no signs of wear after a good wiggle. Sometimes, I figure it's more likely to leak if I mess with it than leave it alone. If it ain't broke and all that..

[lotusflasherman]

I used my first SE for social and business use so clocked up a lot of miles and used to have it serviced by Daytune in Cambridge. They replaced the cambelt at 60,000 & 120,000 but didn't ever change the water pump and it was still on the original pump when it got written off in an accident with almost 150,000 miles on it. That suggests water pumps don't fail due to mileage, mine didn't anyway, but it was only 8 years old when the car 'died'.

I have another SE on SORN that I plan to put back on the road to sell and that's only done 53,000 miles. That cambelt has only done 20,000 miles but is 17 years old so I won't be starting it until I've fitted the new belt from Rock Auto and I have a water pump to go on too. I'm thinking a 26 year old pump that hasn't moved for several years might not now be too reliable.

For my Eclat, Lotus specify Wellseal (bit like the old brown/gold hard setting Hermetite for the old fogies) for paper and headgaskets and RTV between some non-gasketed aluminium/aluminium surfaces. I'll be using Wellseal on the Elan pump gasket - when I bought it I could only get a BIG tube so plenty to use up still. Small tube here - Wellseal-jointing-compound-100ml

[bbjon]

When I picked up my car it had recently been put back on the road after sitting around since the mid 1990s - the belts had been changed but not the pump. Within a thousand miles the water pump ran it's bearing - I guess inactivity is more likely to promote corrosion than regular spinning?

On the wellseal front I rebuilt the engine of my old excel last year and I can vouch for that stuff! The engine hadn't been apart for about thirty years and getting the mating faces clean was outrageously difficult.

[HJ2]

AIRTEX PUMP BEWARE!

So, the new pump is in, and I'd like to share some thoughts and observations as I have seen a strange thing!

The leaky pump was an Airtex one, just like it's fresh replacement now.
The old (only 500 KM!) pump leaked on the gasket between pump housing and engine block. The shaft was still watertight and there was no free play on the shaft. The leak was on the forward top side. I used the paper seal + RTV on both sides of the seal. I remember having troubles getting the pump in position when I mounted it. I had to cut the mounting holes in the gasket a little bit bigger so they did not foul the pitch of the bolts. It went in, but only just!

Now the 'new' pump... Same brand, also from Rockauto. It did not fit! I just could not get it into position or could only get one bolt in, no matter what. Then I enlarged the holes in the gasket so they were the same size as the bore in the metal pump housing.... No effect and still no fit. Then I measured the diameter and pitch of the holes of the 'old' pump and they were the same

Then I looked closer to see where the pump fouled and it was against the bracket just below the pump (What is this gents? Part of the oil pump? I don't remember...) It turned out that the housing geometry was not the same at this spot. I now suspect that the 'old' pump already had that problem, be it a little less. I slid the pump in place, the lower part first so it passes the bracket, but due to this interference fit, torquing the the top bolts to spec now included the force or momentum to press the housing against the engine block, so I was never able to torque it to spec, thus results in leakage!

I grinded a notch of the housing and the fit was perfect after that.
Pictures to follow soon!

[HJ2]

Problem zone:


Interference area


Grind away (top view)


Grind away (side view)


Back on again


Presto!

[daveiow]

I have been following HJ2's issues with his water pump with some alarm as I have a Cam Belt Kit & Pump ready to go on
The kit & pump was from Rock Auto (supplied to me via Muley)
I have attached 2 photo's of the pump and as you can hopefully see the casing seems to have been modified in the offending area. The modification seem to have been done "professionally" in a lath or jig not by hand with an angle grinder so perhaps this issue has been raised and some pumps have been altered for our fitment.
Anyway I thought I would share this with you and will advise further when the pump is fitted .
Thanks again Jim, see you soon.
David

[HJ2]

Thanks!
Interesting, and yes, that is how the shape should be!
The space behind the bracket is wedged and so is your pump.
The pumps I had were 'rounded' in this area, thus interfering...

[daveiow]

Hi HJ2
Glad you have solved your problem
Hope to see you in Ypres.
David

[HJ2]

Most likely!

[lotusflasherman]

I've got a Rock Auto belt kit with water pump ready to go on my SE that has been on SORN for several years. Thought with everybody recommending them they'd be right but really useful photos to show what mod' to check for before proceeding to fit it. Thanks guys.

[alan e]

I did a belt change with new water pump last year and had no problem fitting the pump maybe its a new problem with them.

[Steve A]

Great team work solving this problem

[lotusflasherman]

Just got round to checking the water pump that came in the Rock Auto cambelt kit ...

Mine is a Gates 41053, listed in their catalogue as Isuzu Impule 1.6 (1990-92). Made in China, with no sign of being modified.. so may have to do it myself..

Front wall thickness is only 3.25mm so will only be removing just enough to achieve clearance ... IF I decide to fit it.

DaveIOW - have you checked the remaining wall thickness? If I removed as much as yours seems to have shown in your photo I'd have a hole or be down to 'paper thin' !

[isuzuowner]

Is there any reason that none of you are using the water pump that was designed for use with the early version of the 4XE1 DOHC engine?

Remember? The Elan engine is based on the 87-89 Gemini JT190 (89 I-Mark RS). With the hydraulic valve lifters and smaller water pump. Before the engine was redesigned for the Storm, Impulse, Stylus, and Gemini...

Gates PN 41056
http://www.rockauto.com/info/64/41056-1_TOP_A.jpg

Beck Arnley 1312064
http://www.rockauto.com/info/31/1312064.jpg

Carter FP1998
GMB 1402060
Cardone Select 5573613

And to the original question of "Do water pumps ever fail?"
Yes.
At roughly 80,000 miles, usually right after the timing belt has been changed.
Water pumps fail two ways.
The less dramatic failure is when they spring a leak around or out the middle of the shaft, producing a nice flow of water out the side of the engine compartment as all of the coolant goes out the leak.
The more dramatic failure is when the bearing fails and the impeller seizes and the sprocket stops turning as the cam belt continues under the power of the crankshaft. The teeth are quickly eaten off the face of the belt and the camshafts move out of sequence. Then you get to pray none of the valves bent.

[daveiow]

This thread brings to mind the old saying "Just because I'm paranoid doesn't mean their still not out to get me"
I've looked at my modified pump and there seems to be a reasonable amount of metal there.
What I am concerned with is bearing or belt failure as at present I have a 26 year old pump,idler and tensioner and a 6 1/2 year old belt.
The reduced thickness of the pump casing may corrode through in time resulting in a weep but let's be honest I'll be doing it again in 5 years time anyway, that must be better than catastrophic bearing failure, belt breakage with all that entails
David

[lotusflasherman]

Is there any reason that none of you are using the water pump that was designed for use with the early version of the 4XE1 DOHC engine?

Remember? The Elan engine is based on the 87-89 Gemini JT190 (89 I-Mark RS). With the hydraulic valve lifters and smaller water pump. Before the engine was redesigned for the Storm, Impulse, Stylus, and Gemini...

Gates PN 41056
http://www.rockauto.com/info/64/41056-1_TOP_A.jpg

Beck Arnley 1312064
http://www.rockauto.com/info/31/1312064.jpg

Carter FP1998
GMB 1402060
Cardone Select 5573613

And to the original question of "Do water pumps ever fail?"
Yes.
At roughly 80,000 miles, usually right after the timing belt has been changed.
Water pumps fail two ways.
The less dramatic failure is when they spring a leak around or out the middle of the shaft, producing a nice flow of water out the side of the engine compartment as all of the coolant goes out the leak.
The more dramatic failure is when the bearing fails and the impeller seizes and the sprocket stops turning as the cam belt continues under the power of the crankshaft. The teeth are quickly eaten off the face of the belt and the camshafts move out of sequence. Then you get to pray none of the valves bent.

Good question! In my case because somebody on this site listed the parts to order from Rock Auto and I blindly followed that advice. The pump you identify (41056) is currently listed at £69.48 whilst the Gates Pump 41053 is £20.31. On my Invoice from May 2016 it's shown as £16.96 so that might explain why somebody considered that was 'the one to buy'. Could be their intention was to replace cambelt and water pump every 5 years so a cheap pump will do.

Think I'd prefer to pay extra, get the right part and expect it to last over 20 years like the current ones have.

I presume your "roughly 80,000 miles" is personal experience. What age was it?

My experience was different as I mentioned earlier in this thread "replaced the cambelt at 60,000 & 120,000 but didn't ever change the water pump and it was still on the original pump when it got written off in an accident with almost 150,000 miles on it. That suggests water pumps don't fail due to mileage, mine didn't anyway, but it was only 8 years old when the car 'died'."

[isuzuowner]

The Gates name was mentioned specifically, so I that one stuck out as being more relevant. And the Gates brand of the older style one does stick out as being more expensive than all the rest. Not a lot of companies doing both of those pumps. Of the group, excluding that Gates one, they show the older style pump priced at $26-44, and the newer style pump priced at $23-40. No idea what it is on the UK website or if they want a big shipping charge for that expensive export postage.

There were some comments about the newer pumps marked as "Made in China". The Beck Arnley and GMB pictures of the older style pump show "Japan" printed on the front. And the Cardone pump has "Aisin" printed on it, and has the stamped impeller like the original. The cast impeller weighs more. The group of newer style pumps do not look quite as close to factory parts as the older style pumps, though the Airtex would probably be the best choice of the newer style ones.

But it has to be worth a few dollars if the part bolts straight on without having to cut metal.

I never measured the difference in the impeller width or thought about how much more water the newer style pushes. Just another one of those annoying things about the older car and engine that isn't the same and is less common, probably more expensive, and implied to be lesser performing.
But the older style was designed for a 125-135 HP non-turbo engine, with a larger height and width radiator and more grille opening than the Elan. Reading the "water wetter" recommendation, the Elan can use more cooling capacity. One of the Isuzu tech pages says any Elan radiator thinner than 2 1/2 inches does not even meet the size and capacity of the stock Impulse RS radiator.
So there is probably a good argument to switching to the larger water pump to pick up a little more coolant flow.