I bought this car upon returning home from VN in 1973. I used it as my daily driver as a college student. After college and a few life changes, I parked it and it stayed with me for 32 years. In 2012, after exhaustive research, I decided to take it to a very well respected restoration facility. They have done work for Jay Leno, Marriott and even the Emir of Kuwait. My car was in good hands! My instructions to them were to restore it to precisely the condition it was in when it rolled off the factory floor in 1967. They cautioned me about what I was asking, but i agreed to proceed. Six years later, I got it back. It's spectacular! Literally a NEW 1967 E-Type. With that said, it now overheats. As my daily driver in '73, it ran quite warm, but never overheated. The engine was disassembled 100%, cleaned and meticulously restored. The radiator is new. I have not begun to fix the problem, however, I would like some ideas from....anyone...to limit the time I spend scratching my head.
Please let me know if anyone has any ideas.
Thanks,
Mark

 

Hi Mark,
You say it's overheating, does it actually boil over or just read high on the gauge?

Assuming that it's boiling over, the first thing I would check is that the cooling fan is coming on and turning the correct direction.

Then check that you are running 50/50 water & glycol.

The pressure cap would be next -

1. Does it seal on the seat in the radiator neck?
2. Does it hold the proper pressure? Should be able to have it checked at an auto parts store.

If I remember correctly for every 1 psi the boiling point of 50/50 coolant increases 1.5 degrees F.

The thermostat would be next -
Did the rebuilder put the correct thermostat in? Jaguar's can over heat if the wrong style of t-stat is installed. See article on Coventry West website

Jaguar XKE Thermostat Information | Coventry West

 

Could also be there is an air bubble in the circuit or in the pump or a bad water pump. If you have a thermal camera or can borrow one see if the radiator is actually getting hot and that all the relevant hoses are also heated. Could point to the problem. FLIR makes a good one that goes on your phone or a more expensive hand held unit. Were I to bet money I'd bet something got into the loop and clogged the radiator as that is really common in older cars. Best of luck!

 

 

Should have been “drive it 3000 miles a year”

in in other words- a lot of real miles.

 

Thank you everyone,
The usual culprits have been addressed, but no solution yet. Not previously noticed, there is also a problem with the engine bogging down at 4000 RPM's. The restoration guys believe it is due to fuel starvation. They believe the fuel starvation is also causing a lean condition which is contributing to the overheating. The carbs were restored(elsewhere...Terry's I think) and have non-original float bowl needle valves which may be partially blocking the fuel flow.
That's the explanation I've received so far. I'm not sure I'm on board with that theory. If I was doing the work, I would backflush the radiator first. The radiator is new, however, the engine was disassembled completely, so there's a possibility of a blockage somewhere.
It runs hot enough to diesel at shutdown.

 

Thank you everyone,
The usual culprits have been addressed, but no solution yet. Not previously noticed, there is also a problem with the engine bogging down at 4000 RPM's. The restoration guys believe it is due to fuel starvation. They believe the fuel starvation is also causing a lean condition which is contributing to the overheating.

I had this on my S1.5 XKE and the leanness/overheat caused piston land failure. It was the fuel filter on fire-wall plugged with something not visible in glass bowl.

Good luck on this T/S

Rgds David

 

I'll disclose straight off that I'm the manufacturer of the CoolCat fan.I'm not writing here to promote my own products.

Cooling systems are pretty simple, but difficult to diagnose. Fueling can certainly add to an overheating condition, and likely would account for the Dieseling condition. So that's one thing you definitely want to address. To see if the radiator is plugged, simply turn the cabin heat up. That will cause a lot of heat to be shed through the heater core. If temperatures come back, then the radiator is the likely culprit. But since this is happening on a freshly restored car, there are a few things that should be high on your list. The first is the otter switch. The S1 4.2 was the only E-Type not equipped with a fan relay at the factory, so unless one has been added by the restorer, there is a lot of current flowing directly through the switch. Modern switches just aren't up to handling the 7-10 amps required. So make sure your fans are turning on. The other thing to check is whether or not your fan is actually pulling. While the S1 fan motors are not reversible, the 3.8 and 4.2 motors LOOK identical, but spin in different directions. If the wrong fan motor was substituted by mistake, then air will not be pulled through the radiator. The third thing is the thermostat. The correct thermostat for the 4.2 S1 is simply unavailable, don't let anyone tell you different. The best available substitute is SNG Barratt's pn 3731/1. And the ONLY other alternative is Land Rover RNC580 or RNC276 from a Series II Land Rover 2.25, however these can only be installed after machining the thermostat housing cover. (https://www.roverparts.com/Parts/8140). No other available thermostat has the correct blanking sleeve for the bypass.

 

In addition to mxfrank's comments, it sounds like they might have jetted your carbs too lean.
The hesitation @ 4K RPM plus the dieseling, which, by the way, was common for Jaguar's in So. Cal in the '60's.

Also, after all the work you have put into it, because of the tendency for the aluminum head to have corrosion/oxidation-clogging problems that is caused by the water evaporating out of the water-based mixed coolant as it gets above the point of boiling, I would re-flush the cooling system and install Evans water-less coolant:

https://www.evanscoolant.com/

Also, in my experience, the "Otter switch" does not close until the coolant's temperature actually reaches 100 deg Celsius (212 deg. F), otherwise known as the boiling point of water.
Before I sold mine, I was about to rig a bypass toggle switch to switch the cooling fan on at about 70 Deg C to keep the engine under that, and if I own another one, I definitely would have that extra toggle on my dash connected to keep from blowing a head gasket.

 

My personal opinion is, I would not use Evens coolant. Here is my reasons:

• My understanding is that Evens coolant doesn't transfer heat as well as a 50% / 50% water glycol mix.
• After luburcation the oil is used to cool the engine. So if the cooling system heat transferring is reduced, the oil will run hotter. The energy has to go somewhere
• Under steady state driving conditions (say 70mph) an engine will usually reach steady state conditions after 20 to 30 minutes, i.e. the coolant temp, oil temp will stabilize.
• The max oil temp for most oils is 300F.
• I have know idea the temps that the oils running at in my engine. So I don't know if the oil would be breaking down because it is running too hot.
• I don't know if the add heat (because of reduced heat transfer) in the combustion chamber will causing detonation. You can't always hear.
• I don't want to do all the work required to prove to myself that there isn't a downside to using Evan's coolant in my car's engine.
• I don't feel there is anything wrong with using 50% / 50% water glycol mix, if you do the normal maintenance.
• Finally there is the cost .

 

I use Evans in my XKE and I had it in my XKR with no issues. My big concern was corrosion though since I don't drive the car(s) that often I wanted something I didn't have to worry about. My old mechanic got me hooked on the stuff (he used it with success in the car he road raced). However, I learned it is best in a clean build (getting all the water out of an engine, radiator, and heater is a PITA - In the XKE I had a new block, new radiator and the heater was not only new it wasn't hooked up). Heat transfer is lower by around 30% but boiling point is through the roof. I mostly run into it with folks that are racing. But I'd only use it if my primary concerns were either corrosion or overheating due to boiling, it was going into a fresh system (I'm not convinced the flush process Evans specifies works well enough through all the heat exchangers in the car), and I wasn't going to be taking long trips in the car to strange places (where you might not be able to get the stuff, you can add water but it will ruin the effect of the liquid). Here is a good pro and con on Evans that looks pretty realistic: https://greengarageblog.org/17-water...-pros-and-cons

Oh I'd also put it on the short list for mixed metal engines, aluminum and iron, because they can have some rather interesting corrosion issues with water I'd really like to avoid. I think it best for cars where you are pushing the performance to the limits and want to avoid a catastrophic coolant failure (and you have supply) or for cars that mostly sit so you want to avoid the coolant separating and other corrosion problems with sitting cars and water. Not much point for daily drivers I can find. Oh, also, Evans is much safer with pets than traditional anti-freeze so if I still owned a farm I'd likely spec it for my farm equipment. It is heavily used for industrial equipment, something I didn't know at the time.

With a heating problem you need to diagnose the cause first (thus my FLIR recommendation above) and then pick a solution that addresses it. Short of adding radiators and electric water pumps I know of no global cure for a heating issue, you need to start with the cause. (XKEs, particularly those with air conditioners, are notorious (as are most English cars) for overheating in warm climates), but we've been addressing that issue for decades and any good old Jaguar mechanic should be able to sort out the problem.

 

This is the main issue I would be concerned with the older I-6 XKE's that have a history of upper-engine/cylinder head cooling jacket and stud-bolt corrosion.

Once your water mix coolant reaches the otter electric-fan switch's factory set-point of 100 deg C (212 deg F), if there are any air pockets in the system with, the water actually boils out of the glycol mix, which is why when you get a coolant leak you smell it first, because of the steam with glycol traces in it.
These pockets of steam can do engine damage like destroy your engine's cooling water-pump's vanes, impeding circulation, causing engine pre-ignition and blowing a head-gasket.

Notice how their cooling system's steel header tanks have a habit or rotting out, since once the water evaporates from the glycol mix, it condenses inside of the tank as it cools, and the water distilled from your glycol mix oxidizes the carbon steel they are fabricated from.

Add to this the typical low-mileage anti-corrosion package that the bargain-brand off the shelf coolants, have, and you are setting yourself up for general corrosion of the complete system.

Since a completely restored condition Series 1 XKE goes for over $40K and up, I cannot see how using a premium coolant that protects your investment is all that expensive.

 

Hi Enderie
I couldn't agree more with this statement.

Quote:

Originally Posted by enderle

I use Evans in my XKE and I had it in my XKR with no issues. My big concern was corrosion though since I don't drive the car(s) that often I wanted something I didn't have to worry about. My old mechanic got me hooked on the stuff (he used it with success in the car he road raced). However, I learned it is best in a clean build (getting all the water out of an engine, radiator, and heater is a PITA - In the XKE I had a new block, new radiator and the heater was not only new it wasn't hooked up). Heat transfer is lower by around 30% but boiling point is through the roof. I mostly run into it with folks that are racing. But I'd only use it if my primary concerns were either corrosion or overheating due to boiling, it was going into a fresh system (I'm not convinced the flush process Evans specifies works well enough through all the heat exchangers in the car), and I wasn't going to be taking long trips in the car to strange places (where you might not be able to get the stuff, you can add water but it will ruin the effect of the liquid). Here is a good pro and con on Evans that looks pretty realistic:

Thanks for the link, but the article was week on facts and data. It always concerns me when there aren't any references for the data. If this is true
"using a waterless coolant does make an engine run hotter at the cylinder heads. For a high-performance engine, the issue could change conditions by over 100°F." This goes back to my point about possible dentition.

Then there is nothing about the effect os the rest of the engine, i.e the oil temps, the expansion rates of dissimlar metals or exhaust temps.
To each their own. you maybe thing you are fixing one problem but you might be causing more new problems.

 

Hi Tom.
As I said in my post these are MY OPINIONS.
If you feel it is a better product that is fine with me, go ahead and use it. I haven't seen the proof that it is a better product. I won't tell people to use XYZ if I don't know (Have proof) that it is better and won't cause a different problem.

As far as the header tanks rusting out, how many of those were caused by not changing the coolant on a regular bases? Allowing the coolant to become acidic. The same can be said for the engine studs.

 

OK Bob, I would like to clarify a couple of things.

In the first place, my suggestion to use Evans coolant was to Mark, the owner with the problem who started this string, not you.

In the second place, I am not telling you anybody else to use anything.
It is merely a suggestion for Mark to consider as well as obtain more advice/opinions on if he chooses to go for that added option.

Thirdly, your statement:

Your statement is literally a shortened re-wording of a statement of mine that in fact you just got through quoting above:

"Notice how their cooling system's steel header tanks have a habit or rotting out, since once the water evaporates from the glycol mix, it condenses inside of the tank as it cools, and the water distilled from your glycol mix oxidizes the carbon steel they are fabricated from.

Add to this the typical low-mileage anti-corrosion package that the bargain-brand off the shelf coolants, have, and you are setting yourself up for general corrosion of the complete system."

Also, it turns out the Evans waterless coolant actually prevents this problem from happening altogether by having no water in it and also not becoming acidic like

What was your point?

And finally, why do you want to get into a prolonged argument/debate over a product that you do not intend to use especially when it was not recommended to or for you in the first place?

 

This will also fix a cooling problem... Now this is impressive performance out of an XKE (engine swap but you can't put a bonnet on it due to the heat). https://www.bing.com/videos/search?q...1&&FORM=VRDGAR

Turbocharged XKE
True a lot of the problems with water mix coolant has to do with not maintaining it. Thus why I prefer Evans for cars that I have that sit. But again, I doubt it will fix the problem here. My experience is, on a newly rebuilt engine with a heating problem, it is an air bubble in the system someplace (or someone left a rag or something else that is causing a blockage-I've seen mechanics put rags in a build to keep dirt out and then forget to remove them but most often it is air bubbles).

 

Here is another article on the Evans talking both about why you might want to use it in car you don't drive often but also why it really isn't a fix for a cooling problem. It will prevent a symptom (boiling over) but you need a solution that targets the actual problem: https://blog.championcooling.com/201...pion-radiator/ This also highlights that Jay Leno swears by the stuff (his collection is impressive). https://blog.championcooling.com/201...pion-radiator/ (This is from a radiator company).

 

Also, Mark, see if you can find out of your shop used a Vacufill™ Coolant Exchanger with Waste Pump to refill your Jag's cooling system:


If they did not, then see about finding a shop in your area that does, since this booger is known to eliminate the typical trapped air-bubble problem in difficult to flush and drain cooling systems, and have them do it over, just to be on the safe side.

This is also the way to go if you decide on the water-less coolant option.

When I had my coolant drained, flushed and replaced for my 2006 vehicle, I was told to go this route,and it has been behaving perfectly.

 

I'm not familiar with all the changes over the years, but I believe the 4.2 uses a foot type thermostat? If so, look closely at it and do some measuring, as these are the same thermostats in the V12 and later XJ6.

There is a bypass port at the back of the thermostat housing and as the thermostat heats up, it expands and the foot should move to close off the bypass port. From the face of the thermostat housing to the bypass on the later cars is 41mm. Measure your thermostat and see how far it goes. I tried 8 different Waxstat OEM Jaguar thermostats and they only went to 38mm, so 3mm short of closing off the bypass. The thermostat opening when fully hot is only 5mm, so a large percentage of the coolant will never go through the radiator.

The solution is a taller thermostat. I measured mine from the mounting flange to the bottom of the foot and most were 32mm. The wax motor moves the thermostat about 7-8mm when new, and less as it ages, so it never gets to the 41mm we need to block the bypass. I found a Gates, #33188s which is 35mm when cold from the face to the foot, and when I put it in boiling water it moves to 43mm, which is far enough to block the bypass. It had made a noticeable difference to the cooling in my XJS V12, so I'm sure it would make a difference in an E Type too. Never hurts to have all the coolant go through the radiator!

For the later XJS V12 and XJ6 if you order the thermostat form Jaguar it isn't tall enough to work as intended. I noticed on my car there was no marks on the bypass port opening to indicate contact with the foot, it had an even coating of scale that same as the rest of the housing, so that said to me the thermostat wasn't doing it's job.

 

Since my name was dropped in post 9, I just want to make it clear that my recommendation is 50/50 for street cars. Track cars can't use glycol coolants of any sort, so they should be using water and Water Wetter.

With regard to post 19, it should be pointed out that S1 4.2's DON'T have dual poppet thermostats, as they have a sleeved bypass. The best S1 thermostat currently available is SNG Barrat's C3731/1. It's a rough approximation of the correct (long out of production) C20766. But it's as good at you can do for now.