‘t Kreng’s water pump

p.s. the damage to the spark plug caps was caused many years ago by a stone marten.
He/she was handled properly without any animals being harmed in the process!

The last time I reported on this subject there still was a small leak from the slot underneath the water pump. But it looked like it was starting to seal better after each drive. There was no noticeable drop in the coolant level every time I returned home. Though there would always be a tiny trace of coolant from the slot underneath the water pump. At least the driving always was nice!

On the driveway to the former fiefdom “Jongenhof” near Lerop - St. Odiliënberg.

A for the Euregio typical large carré farmhouse and former seat for a feudal lord.

Today I took the car for a 2½ hour drive, but not before I wiped of all traces of coolant from the slot. During this drive the temperature gauge remained rock steady at its normal position, with the needle just touching the ½ mark. The coolant light only lit up briefly when starting the car. And when I returned home late in the afternoon, there again was the mandatory check for any leaks. The slot and the area underneath were completely free of coolant traces. Success at last I hope. Time will tell!

Fitting ‘t Kreng’s water pump

Two weeks ago I removed the water pump with the idea of reconditioning it again. But on closer inspection I found the new (after market) seal hadn't seated properly. This matched my hunch pretty well. So after exchanging some ideas with various people who should have knowledge on the subject, I decided to bite the bullet and go for a brand new water pump. And as these have become fairly expensive, I decided to also renew the water pump’s spindle bush. And with the correct tool, removing this bush should have been easy.

Sadly though that didn’t work. The available rim at the bottom of the bush was to thin the get enough grip on the bush, as a result the puller slipped through the bush constantly. And because of that the bush got damaged. As there was no way back it was time for a rethink and some appropriate brute force. Using an old reshaped screw driver as a cold chisel between the engine block and bush. It looked fairly crude and messy but it did the job without any damage to the block or the jack shaft. The bush did suffer though!

The remains of the original bush (#145022)

Halfway through the cleaning of the orifice for the spindle bush

After the bush was successfully removed and everything cleaned thoroughly it was time to fit the new bush. And with the aid of a small tool made from a damaged water pump axle and some lubrication, the bush could be gently tapped into position. At least that went quickly and without drama!

This also applied for the next job, fitting the water pump. Again all contact surfaces in the block and on the gears were lubricated. After which the pump slipped in without drama. I only had to help a little with a ring spanner on the impeller bolt (turned counter clockwise) to get the pump seated correctly.

Final jobs before the time ran out on Easter Sunday were measuring the required gasket thickness for the water pump cover, fit the cover and fit the inlet manifold. When I fitted the inlet manifold last year it felt like the threads of one of the mounting holes in the head was damaged. That's why I had mentally prepared myself for this job, and had a thread repair kit on hand. But I needn’t have worried. This time all (stainless) bolts went in without any problems!

Remain the final jobs for later in the coming week;

• Connect all hoses;

• Fill the system with coolant;

• Check for leaks;

• Refit the carburettors.

‘t Kreng’s water pump

Or the never-ending story continues! The last few times I drove this car last year, there remained a noticeable coolant loss. And unfortunately the leakage did not diminish, it started to get slightly worse. So I decided to bite the bullet and remove the water pump to check the condition of all the seals. Time to get the spanners out again!

The biggest advantage of working on a water pump that was fitted not so long ago is that everything comes of very easily. Even the pump itself could be removed simply with a ring spanner, turning the pump clock wise. Which meant that within an hour and a half the water pump was out again.

And with the pump out it was time for a first superficial inspection. I had hoped something obvious was wrong but there wasn’t. So somewhere in the coming week I’ll have to visit a friend’s work shop to use his hydraulic press to remove the impeller and check all parts in more detail. To be continued!

Finishing ‘t Kreng’s water pump: take 3

It’s been a while since my last post. Not that I have been idle, but because ‘t Kreng’s cooling system has been putting up quite a fight. I left this job with “only the coolant hoses and the carburettors left to be fitted. Glad I only fitted the coolant hoses and then started filling up the coolant system. Sadly by the time the coolant level reached the infamous connecting tube UKC2538 the coolant started to leak out, not good. Time to call it a day and have a few beers!

After visiting the shed a few days later to collect my trolley jack I found back some motivation to carry on with the job! The sooner ‘t Kreng is back on the road the sooner I can continue work on the ’76 car!

And when I got home the inlet manifold was removed. But on closer inspection I couldn’t find anything wrong, though there had been a little lack of resistance when pushing the manifold onto the connecting tube. Time to order some new O-rings in the correct diameter just to be sure, taking the necessary measurements from the various parts. And more waiting for parts to arrive.

In the end the O-rings arrived after two and a half weeks! And they indeed were slightly larger compared to the ones supplied some time ago from a UK based parts supplier. Time for the second attempt to fit the inlet manifold. This time there was a noticeable increase in resistance while mating the manifold to the connecting tube. But again no success! While pouring coolant into the system through the thermostat cover a leak sprang from the connecting tube as soon as the level got above the top of it. Some expletives were uttered! At least the water pump itself was still leak free.

And time to remove the inlet manifold again. This time the cause for the leak was rather obvious. The upper O-ring had caught the edge of the manifold opening and got partially dislodged. Time for take three. But first I had to order a new manifold gasket as the “old” one got damaged while removing the manifold.

Sadly I was again let down by a supplier or courier. The gasket should have arrived on Saturday morning at the latest. It didn’t. As the car is booked for its biennial MOT this Wednesday I couldn’t wait much longer. Luckily I stumbled upon a long forgotten stock of gasket paper with different thicknesses, hidden in the attic. So I had a go at making my own gasket. Using the old item plus the inlet manifold as templates. Fairly straight forward, but time consuming. And as it was late in the afternoon by now I decided to call it a day. Oh and I forgot the pictures of the finished product.

So this morning I had a fairly early start for my third attempt. I have to admit that I had used some of the time while waiting for parts to arrive to work out a plan to fit the manifold. In the end I decided it would be better to put the connecting tube into the manifold before adding the manifold to the engine, using telephone pliers to keep the tube as low as possible in the manifold while adding the lower part of the tube into the water pump cover.

And with the manifold and home-made gasket roughly in place I could again start fitting the stainless bolts. These were chosen to reduce galvanic corrosion between steel bolts and alloy engine parts.

Everything seemed to go well, but when adding the second to last mounting bolt, it didn’t want to go in properly. I managed to get it in by hand in the end but it felt as if the thread in the head is on the way out. So I was rather careful to (over)tighten it. Next time the manifold comes of said bolt hole will probably need a thread repair.

And with all bolts tightened up it was time for the dreaded final task. Filling up the system with coolant. I again decided to fill it through the thermostat cover. But when the thermostat house was starting to fill up there was the dreaded sound of escaping coolant. Luckily it turned out to be coming from the coolant hose that runs between the thermostat and the radiator. This was still fitted to the radiator, but the other end was resting on the water pump cover. And after cleaning of the coolant I could conclude that the tube seemed to be waterproof. Result!

Left me with the rather relaxing job of refitting all hoses, the carburettors and the strut brace. But not before these were treated to a good clean.

Final job for tomorrow evening will be topping up the coolant level and hopefully a test drive to see if everything still works as it should.

Update 15-07-2024: Tonight I first checked the coolant system for leaks (there were none) and topped up the coolant level. And after expelling any trapped air and checking the fuel lines for leaks under pressure, it was time for the final test, starting the engine. It started promptly after which I let it run till the temperature gauge reached the ¼ mark. And after that there was the much dreaded final inspection for any leaks. So far everything is dry. A test drive is scheduled for tomorrow evening, and MOT on Wednesday. And hopefully time to enjoy the car afterwards!

Fitting ‘t Kreng’s water pump

The title says it all. But sadly a fair amount of time yesterday and today was taken up watching the race of the year; Les 24 Heures du Mans. But I did manage to fit the reconditioned water pump. Where the old pump had put up something resembling a fight while removing it, the new one went in pretty smoothly. Probably helped by applying plenty of lubrication to all surfaces and the fact I paid some attention to meshing the water pumps gears with the gears from the idler shaft. After which the pump could be turned into position using a ring spanner on the impeller’s mounting bolt and turning it counter clock wise. As easy as that. Oh … and I didn’t change the bearing bush in the block as it was in good condition. And I do hope that within a few years I will be able to built a new engine for this car!

Next job was setting the clearance between the water pump’s impeller and the pump’s cover.. Rather straight forward though it took some time to get the base reading. According to the book you measure the gap between cover and the blocks contact surface (0,40 mm) and add 0,30 - 0,50 mm for the required gasket thickness. In the end I went for a gasket with a thickness of ± 0,80mm from my spares.

With the water pump back in place I could start with the less glamorous parts of the job, cleaning threads and removing old gaskets. Which did take much more time than expected.

So by the time everything was cleaned my mobile phone’s battery was running low, and the Le Mans race was entering its final stages. But it left me with enough time to fit the inlet manifold (paying extra attention to the infamous connecting tube (UKC2538, between the thermostat cover and the water pump cover) and clear away the tools. All in time to watch the final hour of the race on the telly. Refitting the carburettors etcetera hopefully in the coming week or so ... At least full circle with noon yesterday!

Removing ‘t Kreng’s water pump

With the replacement water pump for ‘t Kreng ready, I started on the final job. Fitting it to the engine. But before I could do that I first had to remove the old pump. Starting with the always rather messy job of draining the coolant fluid. But I am getting good at it as I only spilled about half a pint on the drive!

With the coolant drained from the engine I could begin with the removal of all the parts that are covering the water pump’s cover Starting with the coolant hoses, followed by the fuel lines, the throttle and choke .cables, the carburettors and the inlet manifold.

And this left me with the final parts. The water pump cover and the water pump itself. I did have some worries about the water pump’s cover, as they have a tendency to corrode solid into the engine. This being caused by galvanic corrosion between the alloy cover and the cast iron block. I needn’t have worried. The anti-seize paste I used 17 years ago did its job. The cover came out without any problems. The pump itself put up something resembling a fight but lost against my proven extraction tools.

With the pump out it was time to inspect all parts that had come off. To start with the infamous connecting tube (UKC2538) between the thermostat housing and the water pump cover. Those who follow this blog might remember that this tube had been leaking on and of for a few years. And there sure was a reason for that. The two rubber O-rings on the tube had completely dried out and hardened. And as such no longer effective in sealing.

Next item to check was the pump itself. And that too was rather obvious. The water seal underneath the impeller was completely worn. Actually so worn that the spring inside the seal had reached its maximum travel. Leaving the seal free from the underside of the impeller. With the brass bearing cage fitted the bottom of the water seal should be sitting just free of the water thrower disc. In this case there was enough room to move the seal up and down. And air gaps are pretty poor at sealing!

Final item to check was the water pump cover. I have seen a few over the years that were badly damaged by cavitation. Probably caused by incorrect coolant (plain water) in combination with an incorrect set gap between the impeller and the pump cover. But as can be seen in the picture above, this one turned out to be in pretty good condition. Cleaning and reassembly next.

Water pump reconditioning part 2

I left this job with a generous amount of penetrating oil on the water thrower, to do its job in the joint between the water thrower disc and the pump’s axle. And while the penetrating oil was doing its job, I fabricated a simple tool from a flat steel strip (think very thin wrench) to support the water thrower as much as possible while hammering the axle out. But I forgot the folded edge of the disc. Luckily there was enough space for the tool between the oil seal and the bearing. And using the oil seal to spread the load, the water thrower disc came of undamaged. Removing the oxidation on the axle shaft above the water thrower on a lathe certainly helped here!

And with all parts removed from the shaft they could be cleaned in preparation for the final stage; reassembly of the water pump's various parts.

The reassembly of the water pump should have been a piece of cake. And it was, right up to the second to last part; the water seal. But while trying to push it in position by hand I managed to break the carbon ring. This might be explained by the fact that the seal came from my spare parts and probably was well over 30 years old. And as such the rubber had probably become too hard and the carbon seal ring to brittle?

Luckily I did have another water pump reconditioning kit, so that was robbed of its coolant seal. This time I used a small round plastic container to press the seal into the bearing cage without breaking the carbon seal. Sadly the plastic container slipped with less than 1 millimetre to go, and the second coolant seal was fit for the bin.
I am glad these seals are now available separately, so a new one was ordered. But it meant some extra time lost while waiting for the new seal to arrive..

This time the water seal went into the brass bearing cage without any problems. Which left me with the final parts. The impeller and its O-ring.

Next job is getting the spanners out and replacing ‘t Kreng’s water pump. This is scheduled for the coming weekend.

Water pump reconditioning part 1

It’s been a while since the last update on the coolant leak from ‘t Kreng’s water pump. Well the leak is still there, and still big enough not to ignore. Though it looks like it has lessened slightly. Maybe that is just wishful thinking! So I thought it might be a good idea to start reconditioning a water pump from my spares stock. Main reason being to keep the car more or less mobile as long as possible, and to shorten the time it is immobile.

A short search through my spares came up with two good candidates for reconditioning. Though from one I first had to remove the brass cage from the engine from which it originated. Glad I knew were I had stored my home made “cage-puller”, as it makes this job so much easier!

And this pump turned out to be the best candidate. So next job was a trip to a friend’s work shop as he has a hydraulic press and a lathe. And these are necessary tools for removing the impeller from the pump’s axle, and cleaning the mating face for the seal.

Currently the machined impeller is in an oil bath to aid removal of any remaining corrosion. And the axle is positioned vertically in a support with some penetrating oil on top of the water thrower disc. Hopefully this will come off undamaged, as these are no longer available.

And to end a day well spent on things TR7 I spent a few more hours on the interior for the ’76 car. More on that later.