blown head gasket ( i hope)

[zbronco]

I believe I blew a head gasket this weekend and need some help. I have a 302 crate motor, aluminum heads, bought it used with about 5k miles. I have had it running for about 1000 miles no issues. I do not believe it has had temps over 230…. It has not see high rpm's in the 1k milse and ran fine. This weekend at a stop light the engine started blowing white smoke LOTS of white smoke. Checked oil, it looked fine, looked under bronco and could see coolant dripping from the exhaust pipe… so I deduce a blown head gasket..

I am hoping this is just a head gasket, what else should I look for? Is there an easy way to determine if the heads are warped? I have not started tearing the motor apart and looking for some advice prior to getting started.
Thanks in advance

 

[HoldMyPocket]

aluminum heads? might have to tighten the bolts

 

[broncnaz]

X2 on head gasket although it could also just be a intake gasket leak might want to pullthe spark plugs see what cylinder/s is having the issue. then I'd check the torques on both the heads and intake. You may still need to replace the head gaskets tho.

 

[wildbill]

With the alum. heads look at the intake set. Had to do this 3 times to get a good seal not all gaskits are the same good luck. Bill ;D%)

 

[zbronco]

With the alum. heads look at the intake set. Had to do this 3 times to get a good seal not all gaskits are the same good luck. Bill ;D%)

do you have a recommendation on gaskets? It has an aluminum intake along with aluminum heads.

is there any way to id if it is an intake gasket or a head gasket? every time I have pulled an intake the gaskets gets trashed making it hard to find a culprit.

or is the prudent thing to do is just replace the head gaskets

thanks

 

[ObscureMachine]

Torque down the heads (in order) and see if anything changes.

If not, Pull the intake and see if you can see anything. Pull your plugs and look at them. Water / coolant leaking into one will cause the plug to look "steam cleaned" - that will at least give you an idea where it's leaking. If no culprit is obvious, pull the heads.

Oh, and if you use studs when putting your intake on, it will keep the gasket and sealer from getting trashed. Always use a new gasket.

 

[zbronco]

Thanks for the direction. I re-torque the heads, they seemed fine. Pulled the plugs they all looked good.

I was expecting to find a steam cleaned plug.

So I guess I have a blow gasket between a coolant passage and an exhaust port. This would point back to a blown head gasket if I am thinking correctly..

Should I just bite the bullet and start pulling the intake and head(s) off?

 

[broncnaz]

try retorquing the intake as well. really there is no way to blow a head gasket and have the water go directly to a exhuast port. at least one of your plugs should have been cleaner than the rest. After everything is torqued try running it again see what happens.

 

[Thunder26]

I have a feeling it's your intake gasket and I'm betting they are the notorious Fel-Pro 1250
Check this out http://www.ffcars.com/forums/17-factory-five-roadsters/178867-intake-gasket-leak-what-went-wrong.html

 

[zbronco]

I have a feeling it's your intake gasket and I'm betting they are the notorious Fel-Pro 1250
Check this out http://www.ffcars.com/forums/17-factory-five-roadsters/178867-intake-gasket-leak-what-went-wrong.html

WOW, that is some great information. I will pull the intake tomorrow and see what I find. I hope it is an intake gasket, that be the best bad news and an easy fix.


thanks for all of the info, links and advice.. Without this forum my bronco would have never made it out of the garage.

 

[zbronco]

I replaced the intake gasket and resolved the smoke/coolant in the exhaust..

Now my brakes seem a little week... I have power brakes with disk up front. I am pulling a vacuum which is of the manifold. I could not find my vacuum gauge but it defiantly has vacuum. The brakes do stop teh bronco just seem weaker and go to teh floor...

I know the gasket lined up perfectly, what could I have overlooked?
Bronco is idling around 800 rpm


Also it seems to be running hotter... use to run at 185-200 now running between 210-220..

greg

 

[broncnaz]

If the brake pedal is going to the floor then I'd suspect that the master cylinder is bad or you have a leak somewhere. I dont think its related to engine vacuum.

As for running hotter than normal. Did you recheck your coolent level after the gasket replacement? Might have air in the system still. Might also need to double check the temp sender/guage for accuracy. A previous overheat condtion can cause the sender to go bad. Same goes for the T stat it could be bad and may have caused the initial problem.

 

[zbronco]

Update, I replace the intake gasket again to see if I missed something.. It is still running hotter and the brakes are not good..

The brake booster is getting enough vacuum.. I bled the brakes, they look fine. Brake pedal goes to the floor but still stops the bronco

what are the chances my brake booster went out, it is new...It was fine prior to me changing the intake gasket.

 

[broncnaz]

Brake booster will not cause the pedal to go to the floor. It would only cause the pedal to be a little harder to push thats all. So I'd say its astill a bad MC. Might want to check the fluid level make sure your not losing fluid.

 

[ilovemaui]

If the brakes worked fine before you changed the gasket you might have a vacuum leak. Did you put down a good bead of sealant on the front and back edge of the intake?

 

[zbronco]

If the brakes worked fine before you changed the gasket you might have a vacuum leak. Did you put down a good bead of sealant on the front and back edge of the intake?

yes, i put a good bead of sealant on the front and rear rails. I am pulling 15lbs of vacuum from vacuum line.. MC is full of fluid, I bled the brakes today just to make sure I did not have air somehow... The MC is about a month old...again it was working fine prior to me change the intake gaskets.

 

[zbronco]

Found and fixed the issues.. The brakes issue was a bad master cylinder and the temp was a bad temp sending unit.

Thanks again for the direction and suggestions.