Coolant Leak -- Darndest Thing

[gdae]

Basically I look at this site day in day out, and have for years; and now my car has a problem that the techs say is common but I’ve never heard of it before.
So the other day I notice that the NSX had leaked a little antifreeze onto the garage floor. I took it to the shop and their diagnosis was this:
The aluminum of the engine block is porous and the coolant is seeping directly through it. They didn’t say anything about cracks or bad gaskets; they said that the metal on early NSX’s was thin in that area and they just leak.
Actually, this shop had worked on this problem before for the PO, and at that time had applied JB weld to the block to seal it. Apparently, some of the JB popped off and now we’re seeping again.
The solution they propose is to bypass the hoses and radiator and run some sort of sealant through the block. The porous spot would then be sealed (75-80% chance of success, they tell me). Then they’d hook up the hoses again, refill with coolant and off I’d go.
If it doesn’t work, I’m back to either applying more JB or *shudder* replacing the block.

I have never heard of this “common problem” before, and can’t find anything in a search. Anybody else ever hear of this? What say ye?

 

[Dtrigg]

Basically I look at this site day in day out, and have for years; and now my car has a problem that the techs say is common but I’ve never heard of it before.
So the other day I notice that the NSX had leaked a little antifreeze onto the garage floor. I took it to the shop and their diagnosis was this:
The aluminum of the engine block is porous and the coolant is seeping directly through it. They didn’t say anything about cracks or bad gaskets; they said that the metal on early NSX’s was thin in that area and they just leak.
Actually, this shop had worked on this problem before for the PO, and at that time had applied JB weld to the block to seal it. Apparently, some of the JB popped off and now we’re seeping again.
The solution they propose is to bypass the hoses and radiator and run some sort of sealant through the block. The porous spot would then be sealed (75-80% chance of success, they tell me). Then they’d hook up the hoses again, refill with coolant and off I’d go.
If it doesn’t work, I’m back to either applying more JB or *shudder* replacing the block.

I have never heard of this “common problem” before, and can’t find anything in a search. Anybody else ever hear of this? What say ye?

I think you might want to consider a new shop.

 

[GreyHoundSteve]

I don't pretend to be an NSX expert or anything but that diagnosis sounds crazy.

 

[davidf]

Randall you'd better give Larryb a pm on this.

 

[davidf]

BTW, what shop was it. I'll need to avoid that one. You need Carl as your new mechanic.:wink: I have his no. if you need it.

 

[gdae]

I need it!!!

 

[davidf]

Check your pm.

 

[gdae]

Randall you'd better give Larryb a pm on this.

Yeah, I was hoping he might notice.

I think any high-priest of the NSX world will probably tell me what the little voice in the back of my head is already telling me: that's crazy.

 

[nigel]

Someone is on drugs and it might be you if you believe that.
As before, ask the man, Larry B.

Cheers
nigel

 

[NSXGMS]

Basically I look at this site day in day out, and have for years; and now my car has a problem that the techs say is common but I’ve never heard of it before.
So the other day I notice that the NSX had leaked a little antifreeze onto the garage floor. I took it to the shop and their diagnosis was this:
The aluminum of the engine block is porous and the coolant is seeping directly through it. They didn’t say anything about cracks or bad gaskets; they said that the metal on early NSX’s was thin in that area and they just leak.
Actually, this shop had worked on this problem before for the PO, and at that time had applied JB weld to the block to seal it. Apparently, some of the JB popped off and now we’re seeping again.
The solution they propose is to bypass the hoses and radiator and run some sort of sealant through the block. The porous spot would then be sealed (75-80% chance of success, they tell me). Then they’d hook up the hoses again, refill with coolant and off I’d go.
If it doesn’t work, I’m back to either applying more JB or *shudder* replacing the block.

I have never heard of this “common problem” before, and can’t find anything in a search. Anybody else ever hear of this? What say ye?

I don't think this is serious. Very funny though. :wink: :biggrin:

If it is serious please tell us exactly which shop this is so they can be shut down.

Anyway, if you are leaking coolant you either have a blown head gasket or a coolant hose leak. I suppose the water pump seal could leak also.

Talk to Larry B.

 

[nikey22]

You either have a leaky radiator hose or worse a blown head gasket.

the coolant tank has an overflow tube, if you have a blown head gasket, the combustion chamber pressure drives the coolant from the engine into the overflow tank, and fills it up and eventually outflows to the outside.

Consider also the oil filter cooler which is cooled by coolant. Not all cars have this. Is there a leak there?

If the aluminum is "pourous" then why doesn't coolant leak from the aluminum tubing near the front part of the car (white coolant hoses)? Certainly they are the thinner than the aluminum head??... Nice try on the mechanic's part, but he's wrong.

 

[NSXGMS]

Nice try on the mechanic's part, but he's wrong.

Not a nice try. That diagnosis is the most ridiculous statement I have ever heard a mechanic make. Ever. I still don't believe someone who actually works on cars (for a living) said this. Maybe he walked in during a robbery of the shop and the crook, who tied up the owner and stuffed him in the closet, pretended to be the mechanic until the OP left.

I'm still waiting to be let off the hook...

 

[goldNSX]

Actually, I've heard of a thin crack in the engine block in one case where coolant was leaking out.

 

[NSXGMS]

Actually, I've heard of a thin crack in the engine block in one case where coolant was leaking out.

That's far from what this so-called mechanic is saying. He's claiming the aluminum itself is naturally porous enough for water to flow through. The OP notes that this guy specifically denied there were any cracks, leaks or imperfections of any kind.

Apparently JB Weld is less porous than aluminum...

 

[goldNSX]

That's far from what this so-called mechanic is saying. He's claiming the aluminum itself is naturally porous enough for water to flow through. The OP notes that this guy specifically denied there were any cracks, leaks or imperfections of any kind.

Of course, the statement of the so-called mechanic is idiotic psysical nonsense in the highest degree. The OP should bring the car to another shop.

 

[tom4416]

I'd be a little concerned that this is the mechanic the previous owner trusted the car with

 

[gdae]

OK, I've rescued the car with the spongy block and now it's back home in the garage.

My personal diagnosis is that it has a leaky coolant tank. I ran my hand under it and it's wet under there. Incidentally, the ground directly below was where the coolant dripped.

So perhaps a shiny new tank is in my future. It is possible that the tank was exposed to abnormal pressures for some reason, so I'll take it to the local expert asap just to check it out. I'll let you guys know.

 

[tosugrad]

My personal diagnosis is that it has a leaky coolant tank. I ran my hand under it and it's wet under there.

9 out of 10 times if you can't find the leak it the tank. If your car is more than 10 years old it should be replaced anyways.

 

[NSXGMS]

I'd be a little concerned that this is the mechanic the previous owner trusted the car with

Holy crap, you're right.

Have every inch of this car looked over by the "local expert" and the maintenance records scrutinized. Assume your car has been in the hands of a child...

 

[Racerxjling]

Year of the car? Mileage? Do u know if/when the hoses were changed out? Consider changing them out (or at least those by the leak/tank) when you do the tank as well.

Jeff

 

[Larry Bastanza]

I cannot say I have heard of this before, Honda making thin walled blocks. But I guess it is possible.

Take a few pics, that always helps diagnose these things. Get a coolant system pressure tester and bring the system up to about 14 psi, you will see your issue for sure, it may take only a few psi . If you do not then it may just be the coolant tank cap.

Also the tanks do go bad.

Regards,
LarryB

 

[gdae]

Year: 1991
Mileage: Approx. 56k.
The only ones who have ever worked on this car is this one shop. I have a printout of the records for the last 10 years, no mention of hoses. Lots of things like complete removal and replacement with new of A/C system, complete removal and replacement of window regulator, etc.

I'm seriously hoping that a blown head gasket is not involved. The car is a (de-tuned) automatic that both I and the good Dr. before me drove like grandma.

 

[gdae]

I cannot say I have heard of this before, Honda making thin walled blocks. But I guess it is possible.

Take a few pics, that always helps diagnose these things. Get a coolant system pressure tester and bring the system up to about 14 psi, you will see your issue for sure, it may take only a few psi . If you do not then it may just be the coolant tank cap.

Also the tanks do go bad.

Regards,
LarryB

Thanks much, LarryB. Will do.
Incidentally, I doubt they see so many NSX's that they would have a chance to notice a trend.:smile: