Expert: Rob Painter - 12/17/2009

Question
Hello - I have a 95 with about 50,000 miles recently the engine is leaking coolant - dealer said it has a cracked block - they have tried epoxy to seal it no luck - recommend a new engine for a lot of $$ - can you weld an aluminium block ? or is their another way to repair this leak ?  

Answer
Hello,

Epoxy? That sounds like a slip shod way of repair, even for a dealer. Yes, Aluminum can be welded, however it won't successfully work on an engine block because of constant heating and cooling. The repair will not last even for short term.

Cadillacs are a great car, however there are many inherent problems one must know about to own one or they can be a money funnel. I know them very well along with their close to 30 years of making problematic engines.

I remember the big marketing campaign in 1993 about how great the North Star was. It turned out being the same as the 4.1, 4.5, 4.9. A problem!!!!

If the engine was overheated, that was the end, either head gaskets, heads or like in your case a block.

My wife and I were just talking about my passion with Cadillacs. It is a love hate relationship. I love their styling. I love the way they ride. I hate their cooling system and engine design, their constant electrical problems as well as a heater blower problem that can cost over $500 to fix, just to fail again.

The only way to steer away from the constant Cadillac inherent problems is to get an Escalade which does not have the Cadillac engine.

Now, back to your cracked block: There is only one fix and that is to go with a new engine. There is no other option other than selling the car cheap.

If you go with a used junkyard engine, chances are better than not that the engine was subjected to overheating at one time and will cause you future problems.

All the aluminum engines Cadillacs put out overheated for one reason or another. The owners figured that these cars were like those with a cast iron block where they could run it hot until the owner could get it fixed.

Knowing this, I would panic with my Allante and the 4.1 when the temp creaped above the 1/2 way mark. I would either shut it down or run the heat with defroster for the cooling fans even if it was 90 degrees out.

Unfortunately for you there is no cheap fix and I don't want you to throw good money after bad trying to repair this engine with a repair that may not hold over a day's time.

The way I looked at it was that Cadillac figured if you could afford the car, you could afford the repair bills. Of course I have no proof of this, but why else would they make inferior components for close to 30 years?

When pricing the engine, get quotes on a long block and a short block. I am afraid if the block is cracked, you may have future problems with the heads or intake as well, so you need these components checked as well.

One other point to realize and I spent over 10 years with a GM dealer. They may offer a 50,000-100,000 mile warranty, however it will be void if you overheat the engine.

I am in the market for getting a used Caddy for my wife, however when checking these vehicles out I run a radiator pressure gauge first to detect any leaks. I also check the color of the oil, the color of the antifreeze etc.

You can call me paranoid, but I have yet to have a bad Cadillac engine.

Good luck to you.

Rob