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90% sure i just blew a headgasket


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Driving out yesterday everything seemed fine until i pulled up to a light and the car felt like it was running on 3 cylinders. I revved it a bit and nothing changed so i drove over to a street and pulled in to pop the hood. I checked the cap and rotor...both fine. Checked the wires...they were all fine. I fired it up again and still...idling on 3 cylinders or less. So i revved it up again and a big ploom of white smoke shot out the tail. I checked the coolant this time...bubbly frothy mix. I checked the oil though and it was clean. So knowing that i drove the 2 miles back home and parked it. Let me say....holy uncle buck...ive never seem a road completely engulfed in smoke like that from a car. It was impressive.

 

Today though im going to do a compression test to verify for sure. Then the heads are getting yanked. Im really kicking myself i pulled the heads off my spare motor for a build and then didnt get around to it.

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Did the compression test:

 

Cylinders 2/4 each had about 150-160 on the gauge

Cylinders 1/3 each had in the neighborhood of 120-130 on the gauge

 

I had done a compression test on this motor in the past and i know for a fact all the numbers were around 155-160 for all 4 cylinders so this leads me to conclude the passenger side gasket gave up the ghost for whatever reason (aka me probably lol)

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Something has changed it sounds like. If it's a head gasket leak it would seem as though (from your description) that the compression should be much lower than what you are reading on the gauge. I have one low cylinder on my hatch (110 psi while the rest are 145ish) and it doesn't run any different - still idles smooth and has good power. Been that was for several years - probably a burned valve, etc.

 

I would pull the valve covers and inspect the action of the valves on all the cylinders. Something could be not openeing - last time I had an issue just like your's on my 350 SBC one of the rockers had blown apart (bottom of the rocker just ripped out) and the intake valve for that cylinder wasn't opening at all. It was pulling oil past the rings and burning it causing exhaust smoke and rough idle. I replaced that rocker and it's back to it's usual worn-out self :rolleyes:. Maybe you have a push-rod issue, etc.

 

If you don't see anything there - run a leak-down test on it.

 

Is it drinking coolant? Could be a very bad intake manifold gasket that's pushing a lot of coolant into one side of the engine causeing a misfire condition.

 

GD

Edited by GeneralDisorder
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Something has changed it sounds like. If it's a head gasket leak it would seem as though (from your description) that the compression should be much lower than what you are reading on the gauge. I have one low cylinder on my hatch (110 psi while the rest are 145ish) and it doesn't run any different - still idles smooth and has good power. Been that was for several years - probably a burned valve, etc.

 

I would pull the valve covers and inspect the action of the valves on all the cylinders. Something could be not openeing - last time I had an issue just like your's on my 350 SBC one of the rockers had blown apart (bottom of the rocker just ripped out) and the intake valve for that cylinder wasn't opening at all. It was pulling oil past the rings and burning it causing exhaust smoke and rough idle. I replaced that rocker and it's back to it's usual worn-out self :rolleyes:. Maybe you have a push-rod issue, etc.

 

If you don't see anything there - run a leak-down test on it.

 

Is it drinking coolant? Could be a vert bad intake manifold gasket that's pushing a lot of coolant into one side of the engine causeing a misfire condition.

 

GD

 

Its way low on coolant right now. It was bubbling the coolant like all hell. Id never seen it so frothy other than a bad head gasket. Would a intake gasket do that as well? As for a leakdown test...ive heard it mentioned but havent actually done it before so i gotta go look up whats involved.

 

how did the plugs look?were any really clean?

 

None were really cleaner than the others. They were all around the same brownish color to em. Im going to pop that passenger side cover off and inspect the pushrods and rockers. and start going from there.

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Ok just read up on it. I dont have a compressor at the moment so thats out of the question. But it did bring up something interesting. When i revved it up with the top off the carb...smoke came out my pcv hose fitting on the carb....does that point to bad rings too? This engine was running fine yesterday morning and then pow...something went. Guess its time to start pulling stuff off. We are also talking about an engine with around 115k on it that ive had in my possession since 52k.

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Ok just read up on it. I dont have a compressor at the moment so thats out of the question. But it did bring up something interesting. When i revved it up with the top off the carb...smoke came out my pcv hose fitting on the carb....does that point to bad rings too?

 

Probably not - how much smoke are we talking about here? Crankcase vapors do have a smokey apperance to them very often.

 

GD

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Not a lot of smoke. Just a puff that suprised me when i revved it up with the carb top off.

 

Ok new stuff. I just yanked both valve covers and the insides of both are coated in a milkshake...yet the oil is crystal clean. Also cranked the motor over by hand and inspected the valves/pushrods. All checked out to me at least. All are opening and closing as they should be.

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Driain the oil, all the sludge is up on the top or in the very bottom of the pan the dipstick doesn't reach.

 

May have just popped a plug.....or started leaking at one of em........I've had a rash of trouble with those recently. Plugs in the head inside the valve cover. Replace and seal those puppies any time you have a head off.

 

My theory: Steel plug + Alum. block x 25 years of Corrosoin = leaks

 

Or you may have blown a headgasket.....or both.....if the coolant leaks into the oil, raise the oil level to the point liquids are sucked into the PCV port= raised compression(slight hydrolock)= popped HG.

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The milkshake inside the valve covers is often normal on cars that are driven short distances a lot. Doesn't get hot enough to drive out the moisture. It condenses from vapor to liquid near the valve covers where it is being cooled down due to the air flow of the PCV system. It mixes with oil there and turns to that goo that you are seeing.

 

If there's no mixing with the oil then the milkshake isn't a good indicator of head gasket failure.

 

But the dissapearing coolant means it's going somewhere. I would pull the manifold and inspect the gaskets closely looking for any signs of wetness or fail - are they OEM gaskets torqued to 12 Ft/Lbs?

 

How are the plugs? Have you verified spark at all cylinders? The rough idleing concerns me since you should have plenty of compression for combustion - that's why I'm wondering if one of the intake gaskets is sucking a bunch of coolant into the cyliner and causing a misfire.....

 

GD

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You'll obviously be needing a head gasket set. Let me warn you about the cheapest ones on ebay. I got a complete set for $34 but it was missing the little doughnut metal/rubber gasket that goes between the valve carrier and the head. Also, the intake gasket was almost paper thin, and they need to be unusually thick in order to seal. They refunded me, but it took a tussle. Be sure to ask about those two (well, 4) gaskets before buying the cheapest ones. Works, otherwise. cnc:popcorn:

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You'll obviously be needing a head gasket set. Let me warn you about the cheapest ones on ebay. I got a complete set for $34 but it was missing the little doughnut metal/rubber gasket that goes between the valve carrier and the head. Also, the intake gasket was almost paper thin, and they need to be unusually thick in order to seal. They refunded me, but it took a tussle. Be sure to ask about those two (well, 4) gaskets before buying the cheapest ones. Works, otherwise. cnc:popcorn:

 

EA81's don't have the cam tower o-rings because they are pushrod engines.

 

No one around here uses the cheap gaskets - especially for the intake gaskets. That's a well known issue with anything but the dealer gaskets.

 

GD

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OEM gaskets torqued to 16 since that what my book told me to at the time but they have been in there for 4 years with no probs so far. I think thats my next step...time to yank an intake.

 

Would coolant being dumped into two cylinders cause a lower compression reading? If so im leaning towards intake right now since EA81s are not really know for popping headgaskets often.

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Intake is yanked. here are some pictures to show and discuss.

 

IMG_1598.jpg

 

Passenger side intake gasket still stuck to the intake. It looks to me as if its been getting eaten by coolant around the intake passage. Its got a somewhat chewed up appearance.

 

IMG_1599.jpg

 

Drivers side gasket stuck to the head. Looked bone dry.

 

IMG_1600.jpg

 

Engine minus intake.

 

I think this backs up that the intake gasket is shot. It was those two cylinders that were a bit low on compression and it was this gasket that looked funky to me so im leaning towards an intake gasket unless someone else thinks its still a headgasket from the low compression.

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I can't tell - the pictures are just too fuzzy :rolleyes:. It's hard to say really - I don't see a major blow-out though. Most of the graphite looks present. If it was leaking it doesn't look like it was leaking a ton. But again - fuzzy pics. What's the red stuff? You didn't use RTV did you!?!

 

How were the gasket surfaces cleaned? I generally have to scrape them and then take a soft wire wheel to them to get the rest of the graphite off. Then I clean with acetone or laquor thinner and install. The graphite needs clean dry metal to bond with - just like a head gasket. I give them the same level of attention and prep.

 

It can't hurt to try.

 

And yes - your lower comp. readings could easily be from coolant washing the oil off the cylinder walls. Try quirting a bit of oil in those cylinders and see if the comp. comes up a bit.

 

GD

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Its damn hard to hand hold a camera and get a non fuzzy picture that close. Ug idk what to do really i dont wanna yank the heads to find out they were fine but i also dont want to put new gaskets in..button it all up and have the same problems im having now. No rtv on the gaskets. They were installed dry. That red stuff u see is rust i think. I prepped them by getting 90 percent of the gasket off then sanding the heads with a board and the intake with a board to get it all shiny and clean. I then used brake cleaner on both the intake and the heads to get them clean and installed the gaskets.

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Considering the bubbles in the coolant, the lack of a large blow-out on the intake gaskets (it would take more than a drip to cause the misfireing and large smoke clouds, etc), the slightly lowered comp. readings, etc......

 

My advice is to go ahead and pull the heads - it's easy enough to do on EA81's. Then you can inspect everything - might be a valve issue causing the low comp., etc. You have a nice low mileage unit so I would do a head job - even lapping the valves.

 

See what you find and go from there. Pay close attention to the fire rings on the gaskets - that is usually where you will see "carbon tracking" from combustion gasses getting into the cooling system if the fire ring has let go of the block/head. Probably going to want to do a resurface if nothing else - take .020 off the heads on both sides and up your compression. Also check those freeze plugs as mentioned by Gloyale.

 

GD

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yea thats what im leaning towards. I really wanted to send a set of heads out to Jerry DeMoss and have him work his magic on em..along with SPFI pistons and a delta cam. Jerrys compressor is down (or at least it was though) so im going to investigate machine shop prices around here for having heads rebuilt and shaved. If im in it that deep might as well get it the way i want it. Didnt really want to spend that money just now since i do have a 350 4 bolt main chevy block at the machine shop getting built for my camaro but oh well.

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Since intrest is about zero on my coupe..I will probably be parting it out..cause it does HAVE to go... if you want to use my motor until you get yours going..let me know. ( and if I do part mine out.. you have first dibs as always promised on the side badges)

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Hey thanks Connie. I will def keep that in mind. I have two motors right now..the hydro one in the coupe now that is almost ready to be pulled and the solid lifter one that is originally from the coupe. The solid lifter one has 52k on it and the heads already pulled (really wish that wasnt the case). The thought that i have now is to pull the hydro motor, put new headgaskets in the solid lifter motor and drop that back in the coupe and build the hydro motor on the side even though it was the opposite plan before.

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