Hi everyone! Now that my jag starts, stops, and runs, now it’s time for me to try to tackle some other issues.

1969 S2 FHC
4.2 L straight 6

Below are some pictures with context as to the individual issues but I’ll give some clarification here. First is a reservoir that regularly steams when the car is running and I’m not sure what it’s purpose is nor do I know if the flange coming off should be tied into something or not. Steam comes out of what looks like a port or flange or release area and blows downwards towards the battery compartment. I’d love some context as to what this is, why it might be steaming, should something else be connected to it?

Secondly pictured is a gasket that badly needs replaced. Steam leaks out from here whenever the car is anything past cold, and I figure a new gasket can only help, except I can’t find what gasket this is. I have a parts manual and a repair manual, but can’t pinpoint this specific gasket. Can someone maybe help me identify this?

Lastly, I’m going to try to flush the coolant out. I found the valve under the radiator (and successfully opened it and had fluid flow out) but the manual mentions one on the engines too? I couldn’t seem to find it even with the pictures in the manual but maybe I’m just missing it. The maintenance manual suggests putting a hose into my radiator and flushing the fluid out the port until it’s clear while the engine is running. Has anyone tried this? Is there a safer/more effective way to do this? Open to suggestions. With that, does anyone have suggestions as to coolant? I live in Ohio so some sort of antifreeze is required but I wasn’t sure if there was a go to coolant. Another forum on here suggested a super coolant or something that Leno uses, is it worth it? What is it?

Sorry for the exceptionally long post. Hope everyone is doing well

I have steam billow out of this frequently, especially while stationary. There’s an open port/pressure release opening (?) that the steam comes out of. It blows down towards the battery compartment

Detail view of the gasket that needs replaced

Context view of the gasket that needs replaced

 

The part on the firewall is an overflow reservoir for the radiator. There should be a length of line/hose ( - 1/2 inch or so) going from the upper radiator along one of the frame rails to that reservoir. The other part is the thermostat. Does your cars temp gauge work? There is a temp sending unit at the front of the engine in the area of the thermostat. I will take photos and post.

 

The temp gauge works as far as I am aware (the temperature gauge moves as far as I know, but I can't say with certainty that it's accurate). It appears of all the parts for this car, a new thermostat is remarkably cheap! Now that I know what I'm looking for, I was able to find it on SNG Barratt and the gasket! I linked the search page below. Do you know if I need the 74, or 82C thermostat? Do you know which gasket I would need between the top two options? Thanks for the help!

SNG Barratt Search Results

 

The front thermostat housing gasket (C28222), will work with either thermostat. While you have it apart, I would also replace the housing to manifold gasket C23234 (rear of the housing). Either 74C or 82C thermostat should fit. So it is your choice which temp you want it to open. Excellent article on thermostats here.... https://www.coolcatcorp.com/thermost...%20E-Type.html.
Cheers,
Richard

 

Here is a link to great info on Series 2 thermostats:

https://www.coolcatcorp.com/thermost...%20E-Type.html

Here is a quote from that link: "The stock S2 thermostat was designed to open at 75C (168F), but 82C (180F) was recommended for "winter use" and should be fine year round. Late Series 2 cars (starting around June 1969) all came with 82C thermostats for emissions reasons. "

As for ordering the parts... use the 'chat' on SNGB. Either Jeremy or William will reply and they know their stuff. I don't know what is on your car currently, so best if you look at what's there, like the thermostat housing, to make sure. There are different form factors for the gaskets. Again, Jeremy or William will know.

I will get photos of my S2s overflow setup, reservoir, sending unit, etc. The Sending units are relatively inexpensive, so you may want to think about putting in a new one of those.

As for coolant.. Prestone CONCENTRATE (a better deal than buying the ready to use/premix)


https://www.walmart.com/ip/Prestone-..._LIA&gclsrc=ds

When you mix it, use DISTILLED water, not softened or tap water. Also buy yourself a Coolant tester:

https://www.walmart.com/ip/Prestone-..._LIA&gclsrc=ds


Always fill coolant at the reservoir, once you are sure the coolant is topped up at the radiator. If you are not sure, when the car is cool, top up the radiator. Put the heat on so it opens the heater core to circulating the coolant and drive the car to warm it up. Let the car cool and then recheck your levels. I always like to have the reservoir at about third to half full. If it overflows, there's a drain hose.

 

Always fill coolant at the reservoir, once you are sure the coolant is topped up at the radiator. If you are not sure, when the car is cool, top up the radiator. Put the heat on so it opens the heater core to circulating the coolant and drive the car to warm it up. Let the car cool and then recheck your levels. I always like to have the reservoir at about third to half full. If it overflows, there's a drain hose.[/QUOTE]

Just to be clear, order of operations after part replacement would be
1. Drain from radiator valve
2. refill at radiator
3. refill at reservoir (the one I have pictured on the firewall)
4. Drive to warm up with heat on in the car (potentially I have an issue with my heater core, as hot water has previously come out of the footwell vents)
5. Recheck levels

Thanks for all that information! I'll make sure to order both the gaskets when I do, but I will tear it apart first to see what is already installed. Do I need to drain the coolant prior to removal of the thermostat and gaskets? It doesn't make me much difference either way, but if I can avoid a mess, I might as well ask and do it correctly.

Thanks everyone for the patience with my numerous questions

 

I'm going to add another question in here too since I just learned I will need to do this.

What is the procedure for bleeding the cooling system on the 1969 Etype? Is there anything special I need to do? Are there bleeder valves somewhere in the system that I will need to open?

One article I read said to do the following:
1. Jack up front end
2. Fill up radiator as much as possible (I'll also fill reservoir at this point)
3. Start the car
4. Turn on the heat
5. Hold car at higher RPM (will have to do this anyway since car will be cold and it's a Jag)
6. Open/close the bleed valves (unsure where these are) until only coolant flows out
7. Refill
8. Test drive (given the car can have issues otherwise, this always can be an adventure)
9. Refill once cold

Sorry for asking so many questions. I've never done this before and I definitely don't want to mess up something just because I didn't ask. Thanks for the help

 

If your heater core is leaking, it is shot and no amount of work that you do will be worthwhile because the coolant will end up on your feet.

Here is a link to some instructions to remove it:

https://www.jaguarforums.com/forum/e...-steps-263818/

Be sure to mark the cable where you loosened the nut so you know where to reconnect it once the core is replaced. You probably should replace the little hoses that connect to this as well.

and a link to SNG heater matrix (this part is also available on other vendor sites, for you to decide:

https://www.sngbarratt.com/English/#...b-3fdf3aa5d27f


Here are the photos: you can click on them and they will enlarge.

this first one is the hose/line that goes from the neck of the radiator to the overflow reservoir:


Then, the photo of the reservoir. The lower connection is the hose/line from the radiator, the connection at the neck is the 'drain' if the reservoir gets too full and the coolant needs to go somewhere. It's just a long black section of heater/coolant hose that is threaded down through the engine compartment, and essentially just dumps the coolant on the ground.

The third photo is the temp sender. It is towards the front of the engine on the right hand side and about across from the oil filler cap. There are two styles. The correct one for 69 S2s has the spade connector on top. If you order one, it should come with a crushable metal washer.

The last two photos are of the thermostat area. In the side view photo, side under the spark plug wires is the thermostat.

 

Regarding your question about the coolant drain on the block.......it should be located just aft of the dipstick hole and a few inches above it, like the attached example. In your photos, it looks like the drain was replaced by a bolt and sealing washer. A common modification as the drain taps are prone to corroding shut. New taps are available from the usual sources or your could retain the bolt with a new copper washer. Cheers, Richard

 

So I was able to remove the thermostat but the housing is fully stuck. It’s loose on two of the bolts, but the one on the bottom closest to the engine is STUCK. I have tried a multitude of various ways to remove it to no avail. Is there some hidden attachment point or is it just very very stuck. If I can’t get it off I might just have to make due with the previous seal even though it’s old and now has been partially detached from one side. I don’t like that plan but I’m running out of ideas. Thanks again

 

You should not be getting steam emitting from that overflow tank !
I think you need to replace, (as a minimum), the pressure cap, (pressure value is on the top, but is 7 lbs, I think)), and you might have to replace the reservoir itself as it may be cracked. You will see what looks like a pressure cap by the radiator, but it is just a blank cap. It is only used to refill the system. The small bore pipe runs from there to the reservoir tank, which is actually an expansion tank to cater for coolant expansion when hot. This layout is identical to what I had on my 1980 XJ6 and my 1977 MG Midget. The system is filled to the blanking cap, and also the reservoir is filled part-way up. It's normally a pretty reliable cooling system.
Of course if your radiator is partly blocked the car will overheat. Looking at your photos shows what appears as a totally original engine bay, nothing done to it since it was built type of look. People say, "oh, but the coolant is flowing through the radiator OK". Well it may be, but the whole point of a radiator is to spread the coolant out onto a large surface area. Even if the radiator is part-blocked the coolant can flow OK, but there just isn't sufficient surface area of the tubes to cool it.

 

The radiator has actually been replaced in the “recent” past. My dad totaled it at one point and the radiator took a major hit so it has been replaced. It should be fairly good as far as that’s concerned. Thanks for the info though, I appreciate the feedback!

 

Regarding the stuck thermostat housing......do you mean you can't loosen the third bolt, or is is loose but the housing won't come off? In any case there are only three bolts/nuts. If the bolts are out , but housing is stuck, I suggest applying penetrating oil , perhaps several applications. Then try to carefully pry apart using a non metallic tool like a plastic trim tool. Richard

 

i tried some WD-40. The nuts are all off the bolts, but the bolt is stuck in the housing, as in the hole it’s supposed to slide through on the housing is bound tight to the long bolt. I will try a non metallic prying tool whenever I have time to locate one

 

I had great success with PB blaster. Thought I was going to need surgery on my passenger door hinge, but a couple of shots of that stuff did the trick. Let it soak, try working the bolt, repeat.

 

As far as bleeding the system is concerned, are there bleeder valves somewhere that I need to deal with, or do I just fill it, run with heat on, and refill it?

 

A few points:

- An S2 with A/C requires a 13lb cap on the bulkhead header tank, yours is currently 7lbs. Replace it with the correct cap.

- I have to update the CoolCat page. The thermostat and the otter switch have to work together. If you switch to an 82C thermostat, you also need a 90 or 95C otter switch or the fans will run continuously. Best bet is to stick with 74C.

- The block drain was replaced with a plug on all cars after April or May '69. It's not an owner mod.

- I always recommend Zerex G05 antifreeze.It's a low silicate formula.

- There are no air bleeds or secret incantations needed to refill. The best way to do it is to fill through the radiator cap as much as you can, then walk away for an hour. Top it off, then fill the bulkhead tank half way. Run it up to temperature, let it cool off and check again.

 

while it does “have” a/c, it does not work and is fully not hooked up, as in the belt does not even go to it. Should I still replace the cap?

thanks for all the other information, that is incredibly helpful!

 

There's no downside to a higher pressure cap. The system is designed for 13 lbs, and raising the pressure limit raises the boiling point of the coolant. It won't run hotter than is already does, but if you find yourself stuck in traffic on a hot day, it will be less likely to boil over. You may as well get the benefit. It sounds like your old cap is beyond it's use-by date anyway.