LexSurfing

Hey everyone,
I've been having a bunch of problems with my LS400 (still love her though) and I'm at the end of my rope. I just recently had a starter replaced by a mechanic, and the car starts up beautifully.

BUT! There is now engine overheating problems. I brought it in (to another mechanic) and he thinks the head gaskets are blown. The coolant is supposedly mixing with the fuel (or the oil, I can't remember which side...) and causing big issues. Not only is this screwy for the engine, but it also means that the coolant is basically running dry every time. I had to run her for about 15 miles while hot, and I'm worried about what that might've done. There's a possibility that the metal could've been warped, and word on the street is that aluminum engine blocks with aluminum heads are a nightmare for some reason.

What I need are suggestions. Should I bring her to a dealership and have them take a look? Should I get a new engine? Basically, what would be the cheapest repair (while still maintaining quality).

I appreciate ANY insight. I'm open to all suggestions and desperate...

3UZFTE

I'm not sure why Aluminum got such a bad rep, but our motors are pretty reliable when it comes to head gaskets and stuff. That being said, its completely possible that you have blown yours, and need to have them replaced. It is by far cheaper to replace your existing ones as its about the twice the time to install a new motor.

Try bring it to a local shop that you can trust with a good hourly rate, most places will be licking their chops if you come in and say you need head gaskets. I believe a quick compression test between cylinders will tell you which cylinder is suspect. Also another easy way is to test the coolant for traces of oil. That is a tell tale sign of headgaskets is quick to overheat, you coolant will smell like oil, and you'll always be adding too it. I blew HG's in my 3vze pickup, and you wouldn't be able to tell from looking at it, but it would go through about a gallon of coolant a day. You can always try that Bar's Stop Leak, but it's only going to slow down the leak instead of fixing it.

Good luck.

Rey

Running it for 15mins while hot is an easy way to kill the head gaskets.

shawnlexus

sounds like a head gasket, surprising for a 1uz. Check your compression, pull out your oil dipstick and smell if antifreeze is in the oil? Does the car have an antifreeze leak?

LexSurfing

Yeah I think the antifreeze is leaking too. It's sad watching my gal bleed to death like this...
I really appreciate your input. I'll check to see if there is a reputable place I can bring her to get it looked at professionally. I'd much rather replace the HG than get a new engine.

Are most mechanics able to do this type of repair? The one that I brought it in to refused to attempt it

RA40

iTrader: (6)

He probably isn't familiar with the engine to feel comfortable. Find another shop, it also indicates that he will be unfamiliar with other maintenance aspects of your car.

randal

Most "good" mechanics could change the head gaskets. However, this engine requires more work because of the overhead cams vs a typical and more familiar pushrod engine. Your mechanic will be removing the timing belt in the process, so you might consider having some more items replaced while he is in there. Personally, I would consider having the TB, water pump and pulleys replaced(the so-called 90k mile service) along with the head gaskets especially if they will soon be coming due. It will cost more money initially but save you $$ in labor in the long run.

3UZFTE

A general rule of thumb in life is if your going to pay someone, you pay them to have it figured out before, instead of figuring it out along the way. They both tend to be expensive, but at least you know what your getting.

LexSurfing

I was speaking with a mechanic who suggested using Blue Devil as means of stopping the possible leak. Any suggestions or opinions on this one?? And if it does seem to "heal" the leak, would that just be temporary?

deanshark

Don't use any kind of "stop leak" garbage. I would bring it to the dealer (I hate making that suggestion) and have them diagnose it, they know the engine. From there see what your best bet would be. Instead of going to different guys who say "It might be this or it could be that."

NisMax

How high is the coolant temp gauge going over the halfway mark?

LexSurfing

It extends as far up as possible. And does so about 15-20 minutes into the drive

LexSurfing

Would this problem also be why the heat failed?

deanshark

Yes. If there's no coolant then there is no heat. If you are leaking, or burning, coolant then you will have air in the system which will make the gauge go all the way up even if the engine is not hot. A blown HG will also do that with the gauge while cold but it will come back down, that usually happens as soon as you start the car.
You say it over heated, are you saying that b/c the engine actually was hot and coolant overflowed or just going by the gauge being all the way up to hot level?

JBrady

Overheating the engine causes the metal of the head and or block to warp which is what allows the headgasket to blow. To properly fix a blown head gasket due to overheating your mechanic must make certain that BOTH the head and block surfaces are straight. After overheating this is not likely. It requires re-surfacing the heads and the block as necessary to achieve a flat surface otherwise you will likely blow the new gaskets as they will only work correctly with flat surfaces.

As mentioned this work requires complete engine disassembly and is obviously labor intensive. As for me I prefer a factory assembled engine over ANY rebuild. A factory engine can go over 200k miles (often way over). How many "rebuilt" engines last this long?

JDM importers "claim" their engines have 60-80k on them but there is no way to be certain. Personally I would buy a $500-700 used engine with a warranty from a JDM and swap it in.