Talk Morgan Forums Morgan Sports Cars Maintenance & Servicing Coolant system flush and antifreeze change.

Good post Sewin

I'm also a fan of Prestone products, their antifreeze is actually good for 15 years although they do recommend you change it at year 10. It is also fully compatible with all colours including the red typically found in a Duratec, however when switching to the Prestone stuff a good flush is always recommended. Monty was well serviced before I bought him, but I always like to base line my car's maintenance schedule as you can never be 100% sure if elements like a coolant change were actually completed.

As I'm about to do a coolant flush/change it's helpful to know the capacity is 10 litres but you can only manage to drain down roughly 6 litres, of course this is common to all liquid cooled engines with a heater circuit so presurising the system with my hand pump cooling system tester has always been my solution as it forces far more of the coolant out.

Also, as I live in a very hard water area I'll be avoiding tap water completely, I've bought 25 litres of Triple QX de-Ionised water from Euro Car Parts, it's £16 which you could argue is expensive for water, especially as most of it will get thrown away during the flushing process.

https://www.eurocarparts.com/p/triple-qx-de-ionised-water-25l-553772350

However, my thinking is I'm only doing the job very infrequently and whatever I ultimately leave in there after the flush and final fill will be sat there for 10 years, it seems a small price to pay particularly when I look at the state of the corners in my shower at home after just a few months of limescale buildup.

I also have a vacuum filler which removes the need for the bleed process, using my compressor the venturi design of the vacuum filler kit kit allows me to put the whole coolant system under significant negative pressure with all hoses literally sucked flat. The tank on the vacuum filler kit is filled with a fresh mix 50/50 mix of pure de-Ionised water and Prestone concentrated antifreeze, then with the system under negative pressure the tap is opened and the new fresh coolant is rapidly drawn in completely filling every void.

I've owned Monty for just over three years now, and despite his robust service history prior to my ownership I always feel it's better to do these jobs myself. It's the same with changing the brake and clutch fluid every two years, replacing the coolant myself every ten years is the only way to guarantee in my mind the job has been done and properly recorded, and of course the only way to ensure these jobs are done correctly with quality fluids.

Couldn't agree More Montegue,

For years I thought Prestone was cheap old stuff, probably because it was sold in Halford's ( not the only source)and the yellow bottles don't inspire either, but I was educated by a racing mechanic and I really haven't looked back. I have even done the test using another well respected and known product then repeated it straight away using Prestone and what still came out was filthy. Just to confirm it wasn't the two flushes that did it I flushed my son's car both times with Prestone and the second flush was totally clean! Make what of that you will but it sold it to me!

You Didn't say whether or not you were going to use the Prestone flush first. Of course garages when they tell you they have flushed the cooling system don't do anything other than change the fluid. As I said, when I drained my old fluid out it looked like new. It was only when I used the flushing agent that I discovered just how filthy with retained muck it was.

Re. the bleeding, It is the simplest coolant change to a car I have ever done, there really is no issues and a couple of flushes allowing the stat to open fully flushed the whole system and as you have to have the thermostat open to achieve this I found this to be the simplest method.

De-ionised water is obviously the best but I just stuck with the trad Distilled water for the final fill. My water here is very soft, we have no limescale issues at all, not like when living in Kent! However if I had hard water I would be a bit reticent about using tap water to flush it too. I'm like you in that I really don't trust what I am told about my cars service history or what a garage writes as opposed to what it actually does...... I've seen the lies first hand and suffered from them myself too many times. Yes, I too have to base line all my cars that I get which aren't new, and in fact 18 months ago I bought a new Suzuki Jimny as a house car, fishing and dogs etc. for our small Welsh farm roads here and it's never been back to the garage and I have no intension of it ever going there either.

I was in a main dealer a few years ago and I heard the mechanic being given a car for an oil service and he was told "no filter needed, just an oil change! Two things here, they fit the cheapest sh!t anyway so why would they expect it to function well for two years? And why not fit the best as its only a tenner more anyway.

The final straw for me was my sons car went in for an MOT and and oil service to a respected independent. I gave him my card when I dropped him off as it was mayhem and I couldn't park. They charged him just shy of £400.00 Dick Turpin on the till obviously! When He got home the car had not been touched, black oil (petrol engine polo) cabin filter filthy, air filter filthy, washer bottle empty tyre pressures all different. When I serviced it the oil filter cartridge was the cheapest aftermarket option available from a previous service they had done and it was so knackered it had splits in the internal folds. That was it for me, Now no twot touches any of my cars anymore. I'd hoped at 60 odd that I could off load some work but clearly not so I'm back at it again on all the cars!

Hi Sewin,

Sounds like you've really suffered the cowboys there, sadly it's an all too common story

One of reasons I love Monty is he's comically simple to maintain, I can fully service him properly almost in the same time as it took me just to remove the under-tray from my Aston Martin V8 Vantage. I sold that car as all the parts and even basic consumables were stupidly expensive, I also almost felt blackmailed into having it serviced by a specialist as people who buy Aston Martins expect to see that in the service history when it comes time to sell.

When I replaced my 470hp Bamford Rose tuned V8 Vantage with Monty all my friends said I was mad, but the truth is I had more fun in Monty in the first month of ownership than I had during the entire two years I owned the Aston, and for me, properly maintaining and developing my Morgan are key elements to the pleasure I take from owning the car.

Yes, I'm completing a Prestone treatment too, I've noticed what I can only describe as wet clay deposits in Monty's header tank. It's only minor but I'm certain It'll be accumulating elsewhere in the cooling system so I want it out, the tank itself is coming out and getting the Steradent tablet treatment followed by a session in the dishwasher, I've seen this approach recover horribly yellowed plastic header tanks before so I'm fully expecting Monty's to come up like new.

If the Duratec in a Morgan is as easy to bleed as you say, I'll likely not pressure up the system or bother with my vacuum filler, I'll simply follow your 'Bit at a Time' method using my 25 litres of de-ironised water, it should be just enough for three of your quoted 8 litre drain and refills. The first will be with a litre bottle of Prestone treatment added, the second will be a pure re-ironised water flush to get rid of the chemical and whatever what it picks up, the third will be to see it run clean and then to create the final 50/50 mix with Prestone concentrate.

Monty has already enjoyed a set of new plugs and three engine oil changes by yours truly since buying him, having also changed the gearbox and diff oils earlier this year and gone through the brakes too (new uprated pads fitted); this weekend's coolant and brake/clutch fluid changes will largely conclude my maintenance baseline mission for Monty.

I can then follow a tightly controlled schedule of proper maintenance, and from a known trusted starting point

Thanks again for your post

Are you sure we're not related? Blimey we are certainly of the same school of maintenance though!

I found the header tanks compartmentalised structure difficult to clean in the end I used a washing machine liquid and moved it around under the water in a bucket until all compartments were fully filled and left it to soak for a few hours. That cleaned it quite well and back in the car with new fluid, it looks new!

I really think you will be amazed at just how filthy the first flush drain comes out. As I said, I chose to leave mine in overnight and by the amount of foaming it produced by the next morning it was clear it had still got a job to do even after I had run the car at temperature for 40 minutes after putting the flush in the previous evening.

If you know your way around a car and can interrogate via the OBD 2 port ,then even modern cars are not difficult. Just look at the service receipt and see exactly what they did and used for the bill they gave you, Bloody unbelievable! So your money certainly didn't go into your car, rather their pocket! Just look at oil, where did £40 worth of a good oil that you can buy suddenly become £95 + vat for a bog standard oil of an.... that'll do grade that they buy in bulk.. ie. bet my Morgan would get blue drum 5W-30 instead of the 5w-40 it should have, and it certainly wouldn't be nano-tec ++ racing oil with the correct additives. VW... Oh we've used long life oil Sir.... yeh, they use the same oil in all the cars, that's a fact!

Service record.... tusch! I always sell my cars privately with a complete service record from my work undertaken, they are presented well and for the last 30 years the first to see has always bought them. You can tell a good car when you see it and there is an ever increasing buyer base who are looking for just that car with that history. Don't forget, if the stealers have shafted us then they are treating everyone the same! Oh! and all have sold within the first week. Know the correct value and price it accordingly and you'll get good money for it too!
Next time you have a tin top serviced go through everything they said they did.... start with the cabin filter.... biggest scam there is ..... never gets changed and it's a three minute job on most cars too. make sure it goes in with a full washer bottle and see what they charged for that too.... still trust them? Mark your oil filter if its a spin on and cartridge type top can be marked against a known reference point. Some might think me paranoid but I haven't been wrong yet. and finally I reached the conclusion why pay them to do nothing. What has caused this level of corruption... PCP deals, they don't own it ,they drop it for service, they drive off when done... never look at the car!

Thanks again, I was changing the brake & clutch fluid yesterday using my new pump up pressure bleeder kit, I'll post some videos on TM later.

That leaves today to move on to the cooling system

When I had the Plus8 I was going to swop to Prestone coolant. Previous coolant changes were ok but for full draining there were drain plugs in the block to let trapped fluid escape. It was a straight forward job, drain, flush ( inc back flushing the rad), refill and bleed. I had the silicon hoses but there was no high level bleed vent so a case of running/ topping up/ squeezing the top hose to coax air to the header tank. A bleed valve would have been good!
The car ran at decent temperature but the fan kicked in more in summer/ slow traffic. The rad was a Morgan aluminium one fitted by a previous owner. Not really up to the job as it seemed to be at it's limit. Under bonnet heat was high! Bonnet extenders in summer plus managing airflow through the rad with blocking off air escaping past the rad helped. The bottom area also suffered from being blocked by panels below the number plate box. Hence ducting to get airflow through to that area. These mods helped a bit and were cheap to do. There was a noticeable difference in running temp from summer to winter. Slower coolant heating and the colder air seemed to reduce rad fan kicking in.
The next job was to get a cold air feed to the filter due to the very high under bonnet temperatures. Not a lot of room on that side, shame the intake wasn't the other side where there was room.
Moved to a Plus Four before working on that.

Sospan, My plus 4 has the ITG cold air intake kit as supplied by williams. It takes air from above the radiator through the grill but... the filter canister is mounted directly above the exhaust manifold, almost touching it in fact,...... and yes it gets blooooody hot. Were I to want to install a hot water system for making tea on the go it's where I'd have chosen to fit it. I'll have to see about raising the mount and shielding it but for the love of God who the hell thought that was a great installation option........ might be good in northern Canada winter though

My first Morgan was a '93 4/4 withthe Ford efi 1.6 engine. The air intake was from the inner LH wheel arch panel via a flexi plastic duct. It routed above the exhaust manifold. There was a small steel heatshield bolted to the manifold but had little effect as it got hot itself. I replaced the plastic duct with similar as it was melting but shrouded it with reflective heat material.
The heater was excellent, the older push-pull lever style for on/off. I liked that dar but wanted the bigger engine for longer distance cruising.......and fun! 3k rpm in 3rd gear......the car felt alive.

Ah the CVH engine, still takes some beating. I liked the pre fuel injection version most it went like the scolded cat! You could change the cam belt whilst eating a bacon sandwich at the same time. Some distributors could cause trouble and from new too but when working well they were an absolute joy! The throttle response was instant and the control it gave just using the throttle was remarkable. I think the most loved engine for me on anything was the Land Rover TD5 the most enjoyed was the Ford 1.6 CVH (carb) engine!

My first Mog was a 4/4 with the carb CVH, knew the Ford bits inside out from working on Fiestas, loved my 4/4, so simple and nimble !