BLOG: A tale of two lucky VDP's - part 5

by Andy Perman

So with the front of the car complete I wanted to take a look at the hot running issue before I got stuck into the suspension stuff. I’d tried running the car on several occasions but each time it seemed to get very hot quickly regardless of whether the electric cooling fan was running or not. And with snow still on the ground in March it clearly wasn’t adverse weather conditions having an influence!

The interior blower fan was not working so I decided to remove the heater unit first although I was sure this wasn’t where the problem was. Well anyone that has had the (dis)pleasure of removing a VDP heater knows what I was about to get into. You pretty much have to remove both front seats, the steering wheel, the dashboard, the control cables and the panel then finally all the elecktrickery. Then from the engine bay, drain and remove the hoses, remove the intake grille and the rainwater drain points. Then and only then can you remove the three bolts that hold the unit in place and remove it from inside the car.

With the unit stood on the drive it was a simple job to replace the faulty fan and get rid of 40 years of dead flies and dust. It also gave access to the heater matrix that once removed I could flush out. Again, it was a bit murky but not blocked or leaking so I was confident there was no fault here. With the heater unit back in one piece and somewhat cleaner I put it back in the car then spent the rest of the day putting the car back together.

With a functioning heater unit I put a good dose of DS3 in the cooling system. I use DS3 to de-scale boilers and heat exchangers and its good stuff. I let it whirr round for half an hour where I noticed no change in the hot running, then drained it out. It was mucky but not awful, kind of like cappuccino. With it refilled with fresh coolant there was no change - zip. Still running hot into the red on the gauge and it felt hot too so that pretty much ruled out gauge inaccuracy. The radiator and hoses were new, the heater and water jacket were all freshly cleaned, so that left one candidate. The water pump.

A week later after tracking down the correct pump (the early engines have a non dished pulley, later ones do) it had arrived. We were due to visit some friends in the afternoon so after checking the workshop manual it assured me the water pump was a half hour job. I had plenty of time. Off came the belt, then back on went the belt so I could slacken the pulley bolts, then off came the belt followed by the pulley.

​Now I had access to the three bolts that hold the pump, again they came out with no drama. The next step said "hold the pump body and slide the assembly out of the engine". I tried. Nothing. I tried a bit harder. Nothing. OK, try giving it a tap, nothing. Bigger tap, still nothing. Tried some swear words. That didn’t help either. Right, got my large wrecking bar and gave it a grunt, definitely felt something move. Gave it some more grunt. Ping! The pump body sheared in two leaving the sleeve section embedded in the engine!

Well I was out of time now and getting a look from the wifey so I swore again, shut the workshop and went out. The following day after speaking to my Dad he assured me by chopping through the sleeve with a sharp cold chisel it could then be ‘collapsed’ on itself and removed. So armed with a chisel and hammer I set about chopping away at it. It was much easier than expected and only took about half an hour before the remains of it came away along with a pile of swarf and rust. With the bits removed I got my first look at the impeller; there was almost nothing left of it. I’m guessing the car stood for many years with the same rusty water in it so the part of the impeller in the water slowly dissolved into nothingness!

A quick backwards flush of the engine to remove any stray pump debris then it was time to fit the new pump. I covered the sleeve in plenty of silicone grease to stop it corroding itself in the engine again. The new pump and pulley fitted perfectly and I soon had it all back together with a new belt fitted. Coolant in then it was time to check if the hot running issue was sorted. It worked perfectly - textbook even. You could feel the thermostat opening and the rush of heat across the radiator. The electric fan cutting in and out periodically and controlling the temperature. Sorted.

​But this had cost me time, time I didn’t really have. I still wanted to get to the 40th anniversary show and there was still plenty to do and that all important MOT to secure.

To be continued………