Head Gasket question... - Toyota Nation Forum : Toyota Car and Truck Forums

xtremeskier97 · 04-20-2009, 07:44 PM

If I do a compression test on my 3vz, will it tell me if I have a very minor leaking head gasket or no?

Every few months I get boil over in my overflow tank. I have a sneaking suspicion that I have a very small leak of coolant going past the head gasket into the cylinders. Once the coolant gets low enough, and enough air is in the system, it then starts boiling over. Does this sound plausible? Is it possible for the coolant to leak past the head gasket into a cylinder, and then burn off, causing my coolant level to go down ever so slowly and then cause the boil over?

Im going to have to replace the transmission VERY soon on this car, and if I have a HG problem, I may just scrap the whole thing and get another Camry/ES300.

Thanks for ANY help!

***JohnGD*** · 04-21-2009, 01:03 AM

Not if you have a block crack that shows up only when warm.

Probably better to check for hydrocarbons in the coolant. I think there are places that put a sniffer into the rad and tell you on the spot.

Jimnist · 04-21-2009, 05:03 AM

With the car cold (sitting overnight), take the radiator cap off and start the car. If you see bubbles in the coolant, that's usually an indication of a blown head gasket.

dans01camry · 04-21-2009, 08:16 AM

Well, to me a logical way is to simply remove the spark plugs to see if there is a different between the piston heads. After changing out the head gasket on a friends 93 Mazda the problematic cylinder had a white discoloration. Also, shouldn't there be at least a trace of white smoke?

davemac2 · 04-21-2009, 01:18 PM

Your boilover is likely caused by super heating and pressurization of the coolant from exhaust gases leaking from a HG leak. Try driving your camry at high speed (70+) for at least an hr and see if you get a consistent boilover. If you do, your HG is definitely bad. Get a sniffer test done as already recommended or do the block test yourself with a kit. The engine needs to be fully warmed up to get a decent reading. You can also pull the plugs before a cold start in the morning and have a look for condensation on the plugs. That's not guarantee though.

dave mc

xtremeskier97 · 04-21-2009, 08:06 PM

I do have smoke in the morning, but with it being 4am, cant really tell color, or if it's even just steam. I'll probably have to pull the plugs on a saturday morning to have a look at the plugs. I might even go ahead and do a compression test at that point also, just to see how it's looking.

Not to sure about the 70+mph driving for an hour or more. I dont go anywhere near that far to work, and I really dont have time to do that, as I work 2 jobs. I might have to see about doing it on a saturday and take a road trip to dallas or something with the family.

Also, is there a more common than not cylinder that the HG usually fails around, or no?

Thanks for all the help thus far guys!

davemac2 · 04-22-2009, 01:10 PM

Quote:

Originally Posted by xtremeskier97

Also, is there a more common than not cylinder that the HG usually fails around, or no?

Thanks for all the help thus far guys!

#6 is the most common: the front one nearest to the transmission.

dave mc

xtremeskier97 · 05-16-2009, 08:42 AM

Quote:

Originally Posted by davemac2

#6 is the most common: the front one nearest to the transmission.

dave mc

Just checked the front 3 plugs. NO condensation on any of them. I havent started the car this morning, so it is cold.

Also, it seems to me that the #6 cylinder would get the BEST cooling, seeings how it's RIGHT behind the fan, no? If it were my logic, I would thing #1 (rear passenger side) would stay the hottest.

Regardless, im going to try to remove all 6 plugs to see if there is any condensation on them. All this without removing the plenum. Not sure how it's going to go, as I know it's hard to get them out without removing them. Just dont want to go through all the trouble.

If I dont find condensation on the plugs, I'll see about a sniffer for the coolant. Anyone know how much that costs? Or where I can buy one?

xtremeskier97 · 05-16-2009, 09:58 AM

I successfully pulled all 6 spark plugs without much trouble. None had condensation on them. Coolant is a little low right now, though I didnt take much time yesterday after it overheated to fill/properly bleed it. I need to do a flush on it just to make sure there are no clogs.

I know that not finding condensation on the plugs is not a definitive answer, so I will still be looking to get a sniffer test done soon.

Any other help would be appreciated!

EDIT: What places test this type of thing, Midas?

xtremeskier97 · 05-16-2009, 03:46 PM

I talked to the guy up at the local Midas. He will be doing a hydrocarbon test in the coolant on Monday when I take it up there. He's not going to charge me for the test, as I went up there after talking to him and he didnt have the fluid. Not to mention I did computer work for him back in the day.

It overheated on me on the way home and there was hardly a drop of coolant in it. I had a gallon of water in the trunk (just for this occasion) so I pulled over and added the gallon. Made it home. Ive properly filled/bled it now. It's out front running with the AC blasting. Not sure Im going to get it to overheat with it sitting. I held the RPMs at 2500 or so for about 5 minutes, didnt see any leaks anywhere externally and the guage didnt go up any.

Is there any way that I can reproduce highway driving in my driveway? Does holding the RPMs up for any length of time really do anything since there is no resistance?

Man, I just want a Tacoma!

davemac2 · 05-16-2009, 09:34 PM

The engine really needs to be under load to produce the overheat. If it overheated on you going to your local Midas on side streets, I'd say it is getting pretty bad.

dave mc

TheKevin · 05-16-2009, 10:02 PM

good luck. i gave up on my 3VZ. i'm putting my car up for sale soon

Luckynumber5 · 05-17-2009, 01:04 AM

Quote:

Originally Posted by xtremeskier97

Also, it seems to me that the #6 cylinder would get the BEST cooling, seeings how it's RIGHT behind the fan, no? If it were my logic, I would thing #1 (rear passenger side) would stay the hottest.

While your logic is not flawed, you are incorrect. The hottest cylinder is number 5, facing the engine bay it is the cylinder closest to the driver.

Overheating problems are tricky to diagnose on the 3vz, it has an iron block that loves to rust and clog small coolant passages like those in the head. You will need to do a proper compression check and a leakdown check to find where the leak is. If there is a leak...

xtremeskier97 · 05-17-2009, 08:27 AM

Quote:

Originally Posted by davemac2

The engine really needs to be under load to produce the overheat. If it overheated on you going to your local Midas on side streets, I'd say it is getting pretty bad.

dave mc

Well, it's not just side streets to get to and from Midas from where I live. I have about a 5 minute trip on 70mph interstate, about 10 minute trip on a 5 lane highway that is 55mph, and then the rest is side streets. Not to mention I hadnt filled it and properly bleed it before going to midas, because I was going to let them do their test, and I had read that the radiator needed to be a couple inches from the top so that coolant didnt get sucked up into the tester tube.

So, if they DO find exhaust gases in the coolant, then it is DEFINITE that I have a HG failure, correct? Because if it IS a HG failure, and Im already needing to replace the transmission, then Im just going to get another car. Im tired of dealing with this thing. Ive only had it a little over a year, and Im ready to drive it off a cliff.

xtremeskier97 · 05-18-2009, 06:45 PM

Well, I got the coolant tested for hydrocarbons today. Came back positive. So, im looking to replace the engine and transmission with a low mileage JDM combo from ebay.

Anyone have any recommended sellers of JDM combos, even if they ARENT on ebay?