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You may find that the bottom of your brake fluid reservoir is cracked and leaking fluid. Common fault on the old reservoirs as the plastic becomes brittle with age. The crack is caused because the nipple on the end where the outlet pipe is attached is not reinforced and cracks where it joins the flat base. The new one that I bought has a metal sleeve inserted in the outlet tube which strengthens the outlet and it no longer cracks.
First photo of the new one with the metal sleeve. Now been on the car for 5 years and no problems.
Second photo is the old one that I had repaired a couple of times with Araldite but after time it too cracked again.
New brake fluid reservoir with metal sleeve. Old brake fluid reservoir with several repairs.
haha...BINGO!!! you win the prize.
i stopped for gas this morning after about 100 miles. and again noticed a deposit of brake fluid under the engine. and it was too much to ignore. luckily, i had bought yet another (second one) bottle of DOT 3 before i left the motel this morning. i had my toolchest with me, so in the gas station parking lot i tackled the task of fixing the leak.
my plastic reservoir bottle is the original one and has a plastic cloth covered hose running from the bottom of the plastic bottle to the hard metal brake line that goes to the master cylinder. at least i think that's what's happening. it was leaking around the hose clamps. so i tightened them, and..... i made the leak worse than it had been. now, i really needed to fix it!.
i ended up removing the bottle from the clamp (which was loose was and probably the reason the thing was cracked at the bottom hose barb, as shown in your photo) and pulling it off the hose, then reclamping everything securely. but it didn't help. so i asked inside the CENTEX station if anyone knew a place nearby that could possibly do a simple emergency fix. and they sent me to a nice small dealership with a spanking new six stall service center. and they eventually found the crack in the bottle and (almost) fixed it, in that a few drops still fall every minute or so. but tommorrow i'll be home and i have a full DOT 3 bottle with me and i'll be check the reservoir at every gas stop. should not be a problem.
funny thing is i had thought the bottle might have a crack in it too, but couldn't find anything.
anyway, this means that i'll be centering my attention on cooling issues only from now on. it seems that the cutoff for good running is about 70F. anything more and i start having problems. and i'm beginning to think that the raw gasoline was coming out of the two floatbowl overflow tubes and not the AED. it was just too hot in there and the gasoline expanded by the heat has nowhere to go but out the overflow, but was not your typical problem caused by a non-functioning needle valve.
hopefully, i'll be in columbus tomorrow afternoon and at the jag mech on monday and we'll have that thermostat housing off. needless to say, i'm verrrry interested as to what's in (or NOT in) there.
You might solve the petrol problem by reducing the heights of the floats in the float chambers. The float valve will allow fuel to fill the chamber say to 90% capacity and you are getting over 10% expansion. (made up numbers) If you reduce the amount of fuel in the chambers to 80% by lowering the float level then if your fuel expands by 10% it will not overflow. This would not effect the running of the engine unless you were doing 125 mph on full throttle up a steep incline on a cold day and the engine was drawing more fuel than was in the float chamber. (Not going to happen.)
Quick fixes are all very well, but, especially when a bunch of things are wrong, it's necessary to work through the system, cleaning, re-building, and replacing. There are question marks on the head gasket as a cause or a consequence of the overheating. It's probably worth eliminating that first. Have the coolant checked for combustion products. If the gasket needs replacing, it might be tempting to delay other work until it's done. However, I think I'd start some work on the cooling system first.
For the cooling system, I'd start by checking the thermostat. Is it the correct type and is it opening fully at around 70 °C? Is the temperature gauge sender working correctly? Buy an IR thermometer and an accurate mercury thermometer - both will serve you well for checking and testing. After those, there's the radiator and the water pump. Since you are running the car in a hot environment, it may be better just to replace it with a hot climate/race version. I think NAR may currently have some special offers.
For the carbs, it's time for a rebuild. There's almost certainly deposit in the float chambers, the vent pipes may be partially blocked, and the hisser likely needs cleaning out as well. If the otter switch isn't working, the internals have to be replaced or a manual switch added.
Don't avoid biting the bullet.
Last edited by Peter3442; Sep 29, 2022 at 05:17 AM.
You might solve the petrol problem by reducing the heights of the floats in the float chambers. The float valve will allow fuel to fill the chamber say to 90% capacity and you are getting over 10% expansion. (made up numbers) If you reduce the amount of fuel in the chambers to 80% by lowering the float level then if your fuel expands by 10% it will not overflow. This would not effect the running of the engine unless you were doing 125 mph on full throttle up a steep incline on a cold day and the engine was drawing more fuel than was in the float chamber. (Not going to happen.)
sounds reasonable,,,
i've made it to columbus without further incident. weather has been in the 60's. little to no gasoline smell. and am becoming more convinced that it was coming from the floatbowl overflow tubes. and being blown under the car and filling the interior with the smell as a consequence.
the brake fluid reservoir is still leaking and will be addressed this coming week along with the thermostat. i'll attempt to have the upper and lower radiator hoses replaced too. the oil will be changed and filter too. i probably used about three qts for the 2500 mile trip.
i'll attempt to have the upper and lower radiator hoses replaced too. the oil will be changed and filter too. i probably used about three qts for the 2500 mile trip.
thanks again.
It's a good opportunity to do some (messy) back flushing of the engine and the radiator. Cover everything with polythene sheet.
the car's in the shop! mechs and i agreed that the car needs...
1) new brake fluid reservoir.
2) new radiator
3) new thermostat
4) new radiator cap
5) upper and lower radiator hoses
6) carb kits for each carb, mostly to replace the float needles and seats
7) left rear axle bearing
8) head gasket
9) heater core valve.
everything except for radiator was in stock at moss. i've ordered them and having them delivered overnight. ordered radiator from ebay seller and will be delivered in about a week. hoping to have an uneventful trip back to california in about a week or two. in the mean time staying at my sister's house.
i am not surprised at the list of parts and expected that there would be a price to pay for driving this old-new-to-me-car across the country after so many years of little use.
thanks for all the help and advice. it's really appreciated, trust me.
Sounds spot on. Give the cooling system a good flush while you are about it. I'm sure that they will do if they are pulling the head. New Welch plugs may be worth doing while exposed. It would be terrible to put it all back together & then spring a Welch plug leak. They cost peanuts. Also eases cleaning the block of crud. Don't forget to get the shrouded Thermostat. P/N C3731/1* that blocks the radiator bypass port. You want all coolant to pass through the radiator in hot conditions.
Good luck!
Last edited by Glyn M Ruck; Oct 4, 2022 at 10:48 PM.
Sounds spot on. Give the cooling system a good flush while you are about it. I'm sure that they will do if they are pulling the head. New Welch plugs may be worth doing while exposed. It would be terrible to put it all back together & then spring a Welch plug leak. They cost peanuts. Also eases cleaning the block of crud. Don't forget to get the shrouded Thermostat. P/N C3731/1* that blocks the radiator bypass port. You want all coolant to pass through the radiator in hot conditions.
Good luck!
interesting that you should mention the thermostat...
when ordering, i mentioned that i wanted the shrouded thermostat and the gentleman on the phone wanted to talk to a tech guy, so i waited on the line. when he returned he said the tech guy told him that it would not fit under the cover, i have to admit i didn't know exactly what he was talking about, so i let it slide....
as it happens the car has yet to have the current thermostat removed, so i don't know what was in there, if anything, consequently, i'm holding off on the purchase of a new thermostat for now. i may just have the mechs plug the bypass and run it without one.
i'd hate to get the $hrouded one and find out it didn't fit. or run one that let the bypass function at all times.
interesting that you should mention the thermostat...
when ordering, i mentioned that i wanted the shrouded thermostat and the gentleman on the phone wanted to talk to a tech guy, so i waited on the line. when he returned he said the tech guy told him that it would not fit under the cover, i have to admit i didn't know exactly what he was talking about, so i let it slide....
as it happens the car has yet to have the current thermostat removed, so i don't know what was in there, if anything, consequently, i'm holding off on the purchase of a new thermostat for now. i may just have the mechs plug the bypass and run it without one.
i'd hate to get the $hrouded one and find out it didn't fit. or run one that let the bypass function at all times.
Huey, I'd call them (Moss?) back and give them the part number. If they can't supply or continue to be uncertain about the correct one, try SNG Barratt. They may cost a couple of dollars more, but should offer rapid delivery of the correct, shrouded, 70°C thermostat. It may be OK now without the thermostat, but winter is a few weeks away.
I think that it was Wally Hassan who said that ideally he'd keep the cylinder head at 40 to 50 °C and the block at 90 to 100°C. 70°C is a compromise.
Last edited by Peter3442; Oct 5, 2022 at 05:34 AM.
interesting that you should mention the thermostat...
when ordering, i mentioned that i wanted the shrouded thermostat and the gentleman on the phone wanted to talk to a tech guy, so i waited on the line. when he returned he said the tech guy told him that it would not fit under the cover, i have to admit i didn't know exactly what he was talking about, so i let it slide....
as it happens the car has yet to have the current thermostat removed, so i don't know what was in there, if anything, consequently, i'm holding off on the purchase of a new thermostat for now. i may just have the mechs plug the bypass and run it without one.
i'd hate to get the $hrouded one and find out it didn't fit. or run one that let the bypass function at all times.
That's BS from some guy in the UK that has his own thermostat that requires machining of the cover to fit. It might be what Moss carry.
Order this from Barratts. It's their P/N & they make them in-house in agreement with Waxstat. I assure you they fit perfectly with no mods & work beautifully. It's what is in my car and I have a spare living at the Southern tip of Africa.
Barratts today has quite a large in-house manufacturing facility. See green shaded area below. P/N C3731/1* Remember this price has 20% UK Vat added to it which you won't pay or see if Barratts US has stock. If not Barratts gets staggeringly good Courier rates from DHL & will have it there in no time.
Last edited by Glyn M Ruck; Oct 5, 2022 at 02:01 PM.
SNG have a base in the US, in New Hampshire, so orders don't have to cross the water. Incidentally, Moss are not very significant in the Jaguar market in the UK. I don't think they offered anything Jaguar until fairly recently when they bought a US Jaguar parts supplier. For sure, I've never contacted them for anything.
I found Moss and their former iteration to be quite expensive. Then there was the months it took to ship and exhaust for a Triumph I was working on...
I have found SNG to be the most reliable and I always order from the UK branch. They have more stock and the shipping is actually cheaper and the same amount of time to me.
was out to the service center today that's been looking at my car. turns out the block is cracked and has been cracked long before i recently bought the car, according to the mech here in ohio that have removed the head and have had a good look at it. they are looking into finding a rebuilt short block. siad they can have it in the car in a couple of days once they can gets their hands on one.
after seeing the crack today, i'm surprised the car even made it across the country.
on a personal note... i've been staying here at my sister's house here in ohio over the past couple of weeks while the car is being repaired and i suspect she's like to get her life back to normal and have me out of here in a reasonable amount of time. plus i would like to get back to my home in california if for no other reason than to know that everything is still in order. so am anxious to get going
and if you are wondering if i am pleased with the premium used sports car company from which i purchased this car, that assured me that they 'would not sell a car that was not in perfect running condition'. well...i am not. but there is probably little i can do about it. it's not as if i really believed them anyway inasmuch as the car is over fifty years old and never been fully restored. in fact, i was kind of surprised it made it to ohio without some moderate amount of work done to it. but i will say i didnt think they'd knowingly sell me a car with a cracked block!!!
The later 4.2's were known to crack, but the earlier 3.8's were not prone to cracking. Where did it crack? Between the bores I'm assuming. A photo would be great if you have one.
It's probably easier to find a used 4.2 from an XJ6 and drop that in to get you home. Won't be original, but it will look right and bolt in if you use the XJ6 short block and accessories and head from the Mark 2.
You might try Terry's Jaguar for an engine, they have an excellent reputation: https://www.terrysjag.com/
Last edited by Jagboi64; Oct 12, 2022 at 11:36 AM.
The later 4.2's were known to crack, but the earlier 3.8's were not prone to cracking. Where did it crack? Between the bores I'm assuming. A photo would be great if you have one.
It's probably easier to find a used 4.2 from an XJ6 and drop that in to get you home. Won't be original, but it will look right and bolt in if you use the XJ6 short block and accessories and head from the Mark 2.
You might try Terry's Jaguar for an engine, they have an excellent reputation: https://www.terrysjag.com/
the service center told me they hopefully have a source for a suitable (don't know if it's a 3.4l, like the one in the car, a 3.8l or something else), but told me they rest of the engine is fine and they plan on replacing just the short block
i don't care one way or another about the block WRT originality. i just want it to run properly,
oh...and i cracked between the outside wall, halfway between the fourth and fifth cylinder. looks like someone attempted at some time in the past to braze it. there was no evidence of water in the oil, and no evidence of oil in the water.
Last edited by hueyhoolihan; Oct 12, 2022 at 01:17 PM.
Apart from the grace and peace, a 3.4 Mk2 is as tough as they come and keeps going in a condition where other cars would have long given up. In a way, it's a weakness as problems are neglected and the damage just gets worse. Cracking a 3.4 block is relatively exceptional. I'd be inclined to mention it to the people who sold it to you, though any recompense seems unlikely especially after the long journey. It's nice to have an old 3.4 block for its strength (though you may be questioning that at present), while a larger bore offers more torque. Either way, good luck with the work. You seem to have found a good workshop. It may be worth having them go over the car thoroughly and sort everything before you drive it home.
