Lifters are used in engines that do not have overhead cam like a Chev 350, they run on the camshaft that is low down in the engine and in a nutshell operat the valves that are on the top of the engine.

The Jaguar V12 is an overhead cam engine thus the camshaft operated the valves directly (almost).

You should be able to have the rad re-cored, the cores are available. I had mine done last year.

 

A lifter rides on the lobe of the camshaft to operate the valves. There are a few designs, roller which has a wheel that rides on the camshaft, more expensive to produce but are much less prone to wear. Usually used in high performance engine due to very high valve spring pressures. Flat bottom lifters ride directly on the cam and are more prone to wear. The valve lash is adjusted either manually on a solid lifter or hydraulically on a hydraulic lifter. These are used in your dinosaur engines like the small/big block Chevy, FORD, MOPAR. Most modern engines are overhead cam and the camshaft actuates the valves directly either via a rocker arm or directly. These engines have lash adjusters, which are sometimes incorrectly referred to as lifters. The Jaguar engine does not use rocker arms and has bucket tappets that ride directly on the camshaft. Valve lash is set with a shim.

 

My rad is going to be recored. Does that fix last for a long time? I don't want some flimsy aftermarket P.O.S. radiator put in my car. That's why I opted for the recore. That way I KNOW everything lines up the way it's supposed to, and nothing has to be altered to fit, which may be the case with an aftermarket.

 

OK I have a really dumb question, but it happened to me today. I took the jag out for a quick 12 block ( less than 1 mile) drive when I got home the coolant was spilling out everywhere!! My husband opens the hood and the expansion tank cap had somehow popped loose and all the coolant was coming out of there. How does that cap pop off ifit is on securely?? It was literally not in place it was half in and half out of the expansion tank hole.

 

make sure the cap is right. There are 2 caps each with a different rating which i dont know off the top of my head. They are designed so if the coolant heats up and there is too much pressure the rad caps will open instead of the pressure blowing out a coolant hose.

There are a few possibilities.
-The cap wasn't placed properly, which is possible because the overflow tanks cap is more fiddly.
-Something is wrong in the cooling system and the car overheated. This is very unlikely since the car wasnt running for very long so it probably wasn't even hot
- The cap is faulty and coming off at a lower pressure than designed. In this case replace the cap.


If you go to an auto store they will have both in the computer. The lower pressure is the overflow tank. Its something like 12 and 18 but i can't remember.

 

To add to the oil pressure discussion.

This is an old car. The oil pressure gauge isn't designed to read "normal" or "low" it simply gives you the pressure. Gauges like that have to be synced to the engine to tell if if its normal or not for that engine speed.

There is a light on the dash to tell you when the pressure is low. Its one of the red ones. Assuming you light works this is the only time you should worry about it.

When the engine is hot and you are idling it will usually be bottomed out. This is okay and totally normal.The car will let you know that its okay by not giving you that red light.

If that light ever does come on check everything that is going on and listen to the engine...if it is all good to go then the sender or idiot light is bad. These are made pretty poorly and prone to going bad. They also produce a oil leak that runs onto the exhaust and makes smoke.





for everyone going back and for on what fan is which and different people live in different places.....why can't we just refer to them as yellow and black or big and small if we aren't able to tell which one is electric and mechanical yet?

 

The cap is brand new. It was replaced by my mechanic. It says 16lbs on it. It scared the life out of me when that happened!! I seriously started shaking all over. I almost cried even and I'm not that much of a girlie-girl!!

 

Both caps are the same pressure. Originally Jaguar used 2 different pressures but later parts catalogues list the same for both. If the cap was not installed properly it could have been your problem. You now have to refill the system and maybe even bleed the air out. If installed properly and if it is the correct cap for the application even if it builds to much pressure the cap stays in place. It just opens the part that actually seals by overcoming the spring pressure.

Be very careful with hot coolant. If a pressurized system is opened when hot you may get sprayed. At the least it will hurt. However more than likely you will have burns. If it hits you in the face you can be blinded and for sure you will never be a girly girl again. I have sen idiots open an overheating race car in the summer. Not a pretty sight. You do get to ride in an ambulance with it's lights and sirens going. I know if it is scalding hot you will end up in a burn unit with skin grafts. So just be real careful.

A recored radiator is as good as the original. That is the best method for repair.

 

My husband refilled the coolant last night fortunately nothing could spray at him/ us because it spilled out for the way the cap came off the expansion tank. Usually we leave all that stuff to the mechanic but it doesn't get back in until Thursday(tomorrow) for the radiator. It was supposed to be done on the 9th but scheduling probs...

 

Ok, I need to know what motor is compatible to my car (Chevy 350... for example) my rad wasn't the problem I have two blown head gaskets. I'm willing to swap out my motor before I will get rid of this car.

 

Are you absolutely sure of this? Sounds like a mechanic's excuse to stop working on it. He has no clue what he is doing and you keep coming back so he says the engine is shot so you will go away. My first clue is both head gaskets are bad. That is very rare. The other is you seem to have you car "fixed" and then post about how there is a new problem. Supposedly your leak was fixed then the next day more leakage, radiator cap fell off and I am sure more things.

How did he come to this conclusion?

Go to an auto parts store and buy a combustion leak tester. How it works is you put a fluid in a clear cylinder and then you suck coolant from the cooling system into the fluid if it changes color you have combustion gases leaking into the cooling system. This is a blown head gasket. if it is not changing color then your head gaskets are not blown.

Here is a link to what I am talking about.


Doing and engine swap is a ton of work. Putting in a chevy 350 is even more work because you have to fabricate coolant hoses, wiring harnesses, driveshaft, plus a ton of little things.

I would personally get a second opinion.

Where in NY are you?

 

Even if this was the problem (which it probably isn't), why would you bother to ruin your car with an engine swap instead of just replacing the gaskets? Hell a used Jag V12 would probably cost less than a garbage 350 because of blessed ignorance.

 

He said he ran a hot pressure test and combustion test. The combustion test went through the "roof" he said. I'm in Buffalo, NY.

 

Was it a combustion or compression test? These motors have high compression, so the pressures are supposed to be higher than an average car. I'm leaning more towards the idea that your mechanic isn't up to the job.

Both head gaskets were blown in my V12. I opted to put in another V12 only because I got an incredible deal on a used engine that cost less than the price of a head gasket set.
If the engine is bad, you can still find decent used engines for reasonable prices.

 

Here's a good example, but if you spend some time you can find them cheaper than this: Jaguar XJS 84-88 V12 Engine Complete Running | eBay

 

In any case swapping to a different engine would cost you a lot more than fixing the problem.

I'm curious why the first thing that was brought up was "what engines are compatible" as though noone had even considered either putting in new head gaskets, or worst-case, replacing with another Jag motor. Again, sounds like you have a know-nothing mechanic who doesn't want to work on anything that's not a GM product. I can't fathom everyone just jumping right to "oh no, now I have to swap in a 350" vs. "oh, no, let's fix the problem". You didn't even ask the typical questions, how hard is it to change a head gasket, how much would a used (Jag) engine cost, where would I find one. Right off the bat it's a 350 that has to save the day. You really need to find a new mechanic.

I'm sorry but I'm so sick of this argument coming up here day after day and watching people make poor decisions and ruining their cars.

 

Darel, I suspect Angie is merely repeating what her mechanic has told her. When she started this thread she was determined to have the radiator repaired rather than installing "P.O.S." aftermarket parts. That tells me she'd rather spend the time and extra money to have it done correctly.

There are some nice 350 conversions. It isn't something I would choose but there are benefits such as the cost of parts and the ability to find someone who can fix/repair those common engines. Let's face it, the pool of knowlegeable V12 mechanics is quickly disappearing.

Changing head gaskets on these V12s can be a bear. The gasket set is a few hundred bucks, the heads and block need to be checked as well as the valve seats ($) and the tool needed to pull the heads is almost $500 (unless you're lucky and the headstuds aren't corroded). Finding a used v12 isn't a bad alternative!

 

I really don't want to swap out my engine, a friend of mine suggested it. My mechanic told me that it would cost me about $3000 for the gasket job if the heads aren't cracked. He ran both tests I mentioned because my coolant cap popped off. This happened apparantly because of too much pressure. The combustion test showed fuel/oil(can't remember what he said now brain is fried mixing with coolant).One head gasket blown for sure, usually both go he said, however you should change both when doing the job. Let's not forget possible cylinder damage to add into the mix of this honey pot of a mess. I'm just sick over this. I love this car so much.

 

Ok that sounds better. One is blown but if doing one why not do both. That is a reasonable suggestion. $3000 is also not out of the question when you consider labor is about $100/hr and we know that head gasket set alone is $300 or so. Remember a professional is going to make a profit on parts. You will pay a premium on parts and you are paying his labor. He also will quote you to do it right and replace other thing while he has it apart. You may want to get a second opinion before you consider doing anything. Even if you find a used engine there is no guarantee that it is good. Might make sense to repair yours.

I believe you can borrow or rent the head removal tool if you are a JCNA member. I bought one a couple months ago on ebay for $175 and used it for my car.

 

May just sell car as is for very few dollars can't afford to fix it right now.