1983 Cadillac Eldorado

[dariusd]

I have a eldorado 2 door coup that has the 4.1 v8. There is alot of oil that collected at bottom. My mechanic thinks front seal is my biggest problem. I wanted others opion if it is worth changing out intake manifold and head gaskets even through there does not appear o be coolant in oil. I was thinking preventive maintance but my meachanic thinks if not broke dont fix it. We also ran compression test that measured 130 RH and 130 to 160 LH. I also observed that there is a coolant leak seen some at bottom of radiator. Beginning to leak transmission fluid around gasket. Any suggestions and advice is welcomed. Thanks

[Cadillac Jim]

I'm more knowledgeable about the 1990's Northstars but I do have a lot of experience with older cars too, if not the 4.1 Cadillac specifically.

The oil has "collected at the bottom" is a bit vague. From the rest of your post, it seems like you are talking about a wet oil pan. A wet oil pan is no reason to pull down the engine. If you don't need to add a lot of oil between changes, and it is not dripping on the garage or driveway to the point that this is a big problem, I would leave the engine alone.

I would say the same about a tiny seepage leak at a transmission seal. If the transmission fluid level does not go down and you don't need to add transmission fluid more often than, say, a quart a year, I would leave the transmission alone.

I have a Chilton manual that covers the 1983-1988 model years and it says that the minimum compression for your engine is 120 psi. All your figures are better than that. I would leave the valves alone.

If there is a coolant leak at the bottom of the radiator, first you should do a reality check. If the car doesn't use coolant, you might want to wait until you see enough leakage to make a firm diagnosis. If you see steam occasionally or smell coolant inside the car while driving very slowly, take a hard look under the hood in the dark with a flashlight and see if you can find the true source of the leak. If it's in the radiator core, such as from road debris or a rock or whatever, you likely will need a new radiator. If it's between the tank and the radiator, or at the petcock, you might be able to repair it. If you aren't sure, I suggest that you start with a cooling system pressure check if I really wanted to know what was up.

The intake manifold gasket is a very simple job and can be done in an hour or two by an experienced mechanic. But, again, if the cooling system passes a pressure check and you aren't using water, I would leave it alone.

I guess I've pretty well made the point that I agree with one thing that your mechanic said: "If it ain't broke, don't fix it." Other than a possible coolant leak, nothing in your post tells me that anything is broke.

If you do decide to pull the engine and transmission and tear into things, then, with a car that old and likely at least 150,000 miles, then go ahead and do a full rebuild of both. Anything that you don't fix in a car that old will cause regret if you drive it long enough because when you had it apart you were looking right at the old parts, and it does appear that you intend to use this fine car for a daily driver for awhile. But it does seem that your mechanic is trying to please you while strongly hinting that the car really doesn't need major work.

If you just got the car recently, or if you got the maintenance bug after leaving it alone for a long time, then perhaps flushed coolant and an oil change, new belts and hoses, a full tune-up with new plugs and ignition wires, and a transmission service will bring your car to like-new performance and driveability. Don't forget to check the brakes and brake lines, too, including the long brake lines to the rear which could be rusty. And, just because the shocks pass the bounce test doesn't mean that they don't need replacing; if it's been more than 60,000 miles, new shocks and struts could make a major difference in ride and handling, as I myself recently discovered. Then, there are the tires, and you can check the suspension for slack while you are looking at that.

[KHE]

The most important thing to do maintenance-wise in a 4100 engine is to change the coolant and add the Bars Leaks golden seal to the radiator. There is a warning on the radiator shroud or close by telling the owner that GM supplemental coolant sealant MUST be used with this engine. The readon is the engine is a wet sleeve design that used o-rings at the top and bottom of the cylinder sleeves. The sealant seals microscopic leaks that would allow coolant to get into the oil.