Blown Lower Intake Gasket....CRAP!!!!!

Guys, it has happened. I don't know how long this has been occuring, but I went out to the truck to check the oil and the oil was completely fine, clear and I wouldn't have expected anything out of the ordinary.

Until I too a look at what was inside my PCV catch can that is:

http://x12.putfile.com/11/32612530644-thumb.jpg (http://putfile.com/pic.php?pic=11/32612530644.jpg&s=x12)

I thought, what the hell, it is probably just some water vapour frozen in the caught material seeing it was -15c when I was checking this.

I brought it inside and stuck the vial in some hot water to see if I could get the water to separate. Low and behold a lot of the material was indeed water but there was something else too.

http://x12.putfile.com/11/32612574313-thumb.jpg (http://putfile.com/pic.php?pic=11/32612574313.jpg&s=x12)

My heart just sank, this could have been going on for how long? Years? Months? Who knows.....

Looks like the lower intake gasket wil have to be changed and that is what is probably causing my weird idle sometimes in the hot summer days.

Tuff break, Maybe you can get Girlbear to give you a hand. She no longer a rookie when it comes to replacing the lower gaskets. Good luck. Does this mean that you'll have to put off your trip to Hawaii a few more years... :sleep:

Sorry to hear that bro. WHat are you going to do? Do you think you will do the work or a dealer?

I will do the work.

The gasket kit only costs 47 bucks and that includes the lower intake and the upper intake gasket along with the distributor gasket.

I am so bummed right now.

I don't know for sure if it is the intake or the head gasket.

Anyone know for sure how to tell?

If it was the head gasket wouldn't you be losing a lot more oil? I had a jeep cherokee with over 200K on it and when the head gasket went I was losing a quart of oil every few days until I replaced it.

I will do the work.

The gasket kit only costs 47 bucks and that includes the lower intake and the upper intake gasket along with the distributor gasket.

I am so bummed right now.

I don't know for sure if it is the intake or the head gasket.

Anyone know for sure how to tell?
LT, Do a compression test and watch for leak down in each cylinder. If there all about the same. Your head gasket should be OK.

If it helps, I have a 93 S-10 Blazer that blew an intake gasket and acted exactly the same way. It is a longer job than you might first think, so put away about 3-4 hours to do this job. Head gaskets you can typically either hear or see signs of leakage, such as an air sound from loss of compression, or water in your oil. The intake leaking is a massive vacuum leak and will cause a lot of performance loss.

Guys, it has happened. I don't know how long this has been occuring, but I went out to the truck to check the oil and the oil was completely fine, clear and I wouldn't have expected anything out of the ordinary.

Until I too a look at what was inside my PCV catch can that is:

http://x12.putfile.com/11/32612530644-thumb.jpg (http://putfile.com/pic.php?pic=11/32612530644.jpg&s=x12)

I thought, what the hell, it is probably just some water vapour frozen in the caught material seeing it was -15c when I was checking this.

I brought it inside and stuck the vial in some hot water to see if I could get the water to separate. Low and behold a lot of the material was indeed water but there was something else too.

http://x12.putfile.com/11/32612574313-thumb.jpg (http://putfile.com/pic.php?pic=11/32612574313.jpg&s=x12)


My heart just sank, this could have been going on for how long? Years? Months? Who knows.....

Looks like the lower intake gasket wil have to be changed and that is what is probably causing my weird idle sometimes in the hot summer days.


That's too bad ! Your truck has how many miles on it ? 150K or so right ? I suppose that is about right for an intake gasket life.

I was told once that these motors last along time, but eventually eat gaskets, i.e. head, intake etc....

I suspect that while you are in there, you can check for other issues, and get a sense by looking down the valley a the cam, etc how things are doing lubrication wise....take pictures....

I don't know if a reference to what would have to be done on a 99 4.3L would be of any help, but here is the basic sequence....If it's any consolation AllData says...

Disconnect the battery negative cable. Refer to Battery Replacement in Starting and Charging.

Remove the air cleaner outlet duct from the throttle body.

Remove the air cleaner assembly.

Drain the cooling system.

Remove the radiator inlet hose at the water outlet.

Remove the heater hose from the intake manifold.

Remove the water pump inlet hose form the intake manifold.

Disconnect the accelerator control cable from the throttle shaft and the accelerator cable bracket.

Disconnect the cruise control cable, if equipped from the throttle shaft and the accelerator cable bracket.

Remove the accelerator cable bracket from the throttle body and the intake manifold

Remove the accelerator and the cruise control cable bracket from the throttle bracket. Leave the accelerator and cruise control cables and the wiring harness on the bracket

Remove the following electrical connectors:
The fuel meter body assembly
The EVAP canister purge solenoid valve
The idle air control (IAC) motor
The throttle position (TP) sensor
The A/C compressor high pressure switch, if equipped
The A/C clutch switch, if equipped
The exhaust gas recirculation (EGR) valve
The engine coolant temperature (ECT) sensor
The ignition coil
The ignition control module (ICM)


Remove the engine wiring harness from the retainers.

Move the engine wiring harness aside.

Remove the distributor.

Remove the Exhaust Gas Recirculation (EGR) valve inlet pipe from the intake and exhaust manifold.

Disconnect the fuel supply and return pipes at the rear of the intake manifold.

Disconnect the vacuum hose from the intake manifold, if equipped with A/C.

Disconnect the vacuum brake booster hose

Disconnect the PCV hose assembly from the intake manifold and the valve rocker arm cover.

Perform the following in order to remove the left front bolt for the intake manifold:

22.1. Remove the drive belt. Refer to Drive Belt Replacement.
22.2. Loosen the nut for the power steering pump rear bracket at the side of the engine.
22.3. Remove the secondary Air Injection (AIR) reactor pipe bracket nut from the power steering pump rear bracket front stud, if equipped.
22.4. Remove the nut for the power steering pump rear bracket at the front of the engine.
22.5. Remove the bolts and the nut for the power steering pump mounting bracket.
22.6. Leave the A/C compressor, if equipped, and the power steering pump on the power steering pump mounting bracket.
22.7. Slide the power steering pump bracket forward to access the bolt at the front of the intake manifold.

Remove the EVAP canister purge solenoid valve

Remove the lower intake manifold

Clean all sealing surfaces

Finally --- Notice: Proper lower intake manifold fastener tightening sequence and torque is critical. Always follow the tightening sequence, and torque the intake manifold bolts using the 3 step method. Failing to do so may distort the crankshaft bearing bore alignment and cause damage to the crankshaft bearings.

Crappy deal bro... like Gabe said you want your lowest and highest compression cylinders to be within 10% of each other. Remember to crank like 6x when checking, and record the numbers on the first and last crank.

If you have any questions or concerns lemme know... I took a LOT of pictures when I was doing my lower gasket. Let me know how that EGR port of yours looks too. And remember.. you want that gasket surface as clean as the virgin Mary's panties. Oh.. and weatherstrip adhesive is way better around the coolant ports than RTV.

Looks like your catch can mod is useful after all :lol2:

Good luck buddy!

Tony,

I thank you so much for your information.

I just went to the shop and they said they would charge me 3-4 hours for it and I can buy the parts, oil and coolant to bring in.

So the job is not going to be that expecnsive and seeing it is -15c here right now, I can't do this in the parking lot.

This has gotten worse, I dumped and cleaned the catch can, drive for 50 miles and the catch was 1/4 filled with yellow milky sludge.

The oil itself is perfect and is not milky at all so for sure I can't blame the headgasket. Plus the engine is running perfectly and there is no thick plumes of white smoke coming out the back even on hard acceleration.

Thank god for this PCV catch can. It just paid for itself right there. I don't know how soon I am going to fix it. The small amount of coolant you saw there took over 1000 miles to collect and seeing it is collecting there rather than the oil I am glad.

This catch can is a blessing.

I like that catch can mod LT, I'll have to do that.

I can't say anythig else, except I hope that you have a heated shop to use.

I like that catch can mod LT, I'll have to do that.

I can't say anythig else, except I hope that you have a heated shop to use.

Nah, I am having a shop do it for me. It is not that I can't do it, it is that it is too cold to do it here. -15c here right now and a winter storm really.

The kit is only $50 and includes the lower, upper and distributor gasket.

I will supply the oil and coolant.

They said 3-4 hours labor and they charge CDN$70 an hour.

I would rather pay than doing this in this cold snowy weather.

Don't balame you. I sometimes get a mechanic friend to do my work when I just don't want to do the job.

He's starting to heat his shop and make me work on my own vehicles in there when it's cold out.

I'm probably at the same stage as you now. Just maintance, and the odd job that needs doing.
plus 1 or 2 small mods most months

Yea, and once this is fixed I think I will be honestly laughing.

If it was the head gasket wouldn't you be losing a lot more oil? I had a jeep cherokee with over 200K on it and when the head gasket went I was losing a quart of oil every few days until I replaced it.

Yea, that is what I am thinking too and the engine would overheat as well.

Playing devil's advocate here now...

Pause and think, before you get totally in a panic:

Water is a good part of combustion process byproducts. How do you know that you are not seeing cumulative effects of moisture being burned off from a relatively slightly more than normally hydroscopic oil just venting vapor? Given the extreme cold temps you brothers see up in the north - could this be your possibility?

It *could* look like coolant when it defrosts since varnishes can be suspended, along with other combustion byproducts that color the water a ruddy-orange/red.

But to be SURE, before you go nuts - leakdown test the cooling system overnight with a rad-cap pressure pump. Pump 'er up to 15-16 PSI and watch the needle. If it sinks, and there is no fluid spilling out over the sides of the block, there is only one place it is going - through your lower intake and into your center cavity where your lifters and balance shaft are. My garage mechanic demonstrated this for me when mine went. I had internal and external leaks with high, and I mean HIGH rate of consumption on the coolant.

Trust me, this is coolant:

http://x12.putfile.com/11/32612574313.jpg

Not the whole sample, it is fuel vapor plus water plus oil, but the orange blobs are definitely dexcool.

The recent flush I did must've been the last straw.

Well, damn...it's got to be spraying right up at your PCV to be Dex...and it looks like Dex on the close-up photo. Ugh... good luck man. What a waste of XD-3 and a filter too. I anguished over that when I had to get my beast drained of its load of Rotella. *sigh*

Well, damn...it's got to be spraying right up at your PCV to be Dex...and it looks like Dex on the close-up photo. Ugh... good luck man. What a waste of XD-3 and a filter too. I anguished over that when I had to get my beast drained of its load of Rotella. *sigh*

Nah, this dexcool was in vapour form and only settled out after an hour sitting in a warm water bath to get everything separated.

Oh, and no biggie about the oil, it is only CDN$4 per liter so the most I am out total with filter is 20 bucks.

Just out of curiosity, what kind of pressure would you need to blow a head gasket? I could see a rad flush at too high a pressure wrecking a manifold gasket, but not a head gasket.

And I understand that "it would differ from vehicle to vehicle depending on condition" :P

Conceivably, it would not take much. Hose pressure can be anywhere from 20~90 PSI depending on where you lived. Cooling systems are made to take 15-16 PSI or so. I never stuck a hose in a radiator hose or cap opening to flush because of this fear of "breaking" something I always held.

Radiator flushing is usually done with the radiator removed from the vehicle - well, it was done this way at every radiator shop I ever stopped and looked into. *shrug*

Ahh good. This coincides with the information I just found:

you system leaks with 16 psi, usually a water hose has around 40 pounds of pressure

Ok, got an update.

This PCV catch can is a MIRACLE in cold weather.

You know the condensation that develops in your engine during when you are driving in cold weather? Well, that is what is in the catch can and that is what is not going back into the engine. This catch can is separating all that fuel and water out of the pcv gas and allowing it to be trapped and not reburned which is fantastic.

This is what I got in 100 miles since the last photos. No visible Dexcool.

http://x12.putfile.com/11/32715071664.jpg

No visible dexcool means I am not as scared as I once was. I just did a cooling system flush so I am wondering if that had anything to do with the coolant being in the oil?

The mixture was water, fuel and oil and maybe some coolant but nothing you could actually see. The catch can is scrubbing my oil. :D

Also, I never thought that maybe the rad is failing and allowing coolant in the oil.

What do you think?

It is a distinct possibility, as your tranny and oil coolers are in the radiator flow. When I replaced the Radiator in my truck, the connectors for the coolers were good, but the inside of the radiator core was shag nasty looking. Anything that preforated the coolers would also allow migration of the tranny fluid into coolant and vice-versa. I would check your tranny dipstick carefully for signs of coolant before I got off-the-walls stir-crazy. Possibly a seal that holds at operating temps would not hold against flushing pressures if you used either a splice-line flushing tool kit or poked the hose down a rad hose or the rad neck.

I flushed my block and radiator after replacement and running coolant system cleaner with a hose, but - I disconnected both hoses and dribbled the water slowly through the cold engine block after removing the thermostat. I kept dribbling water in for 20 minutes or so until all of the scale and crud blew clean out of the bottom hose (return hose) and nothing but clean water came out. My thermostat sits in a housing with a rubber gasket, so as long as you are careful you can re-use it. But I did not take that chance either and replaced it with a fresh one, it's only like $2 to get. :)

I'm glad I've been reading about all this lately and was referred to do the prestone clean rather than the prestone flush.. It was debateable whether it was the mixing of dexcool and prestone green that killed my sunfire or the flush that I did afterwards. I'm starting to think the latter.

Bet you money it was mixing the orange with the green.

Flsuhing will not cause an engine failure.

Plugged up coolant passageways filled with the mixing coolant precipitate will.

I caught mine early, I ended up with more leaking outside the engine than inside. $537 later I have new gaskets, oil and filter, a new thermostat and an anti freeze flush and fill.

So is it the intake gaket head gasket or neither? Should i feel sad for u or releived? lol

Nothing changed yet.

Still some water in the catch can but that is condensation from the cold weather. Better in the catch than in the engine.

No more coolant has entered the catch can at all. I just don't know where it came from.

you do have plastic lower intake blazterlt, if there was coolent in there i strongly suggest doin the lower intake, it does explain a funky idel on a warm day, if it keeps going you could be in for a biiiiggg shop bill, once you hydrolock the moter it can get expencive. suggested is 60K mi. (95k km) between changing them, if you have more then that seince the last one your living on borrowed time

1995's have plastic gaskets?

i do beleve so, slight possibility im wrong on that one but some vehicals have them back to 89, i know 96 does, and as you know with obdII funny things happend in 95

The real question isn't if LT's Blazer has a plastic gasket, it's really what are we all doing in on a saturday night?

I should be 1/2 wasted by now, and you guys should be almost there :biggrin:

well, so far tonight, i have been with the girl friend (went snowboarding for a couple hours) won 20 bucks at cousins house playen pool and drinken beer, came home to check the board and mail... trashed is fridays after work and when i dont have to possibly plow at 6 am the next day

I went out tonight and had 1 beer. I just don't like to drink like I used too.

Since I'm still new to this clicky place I don't really know that many people yet making it boring to hang out in the pubs.

I might have to take the 1 hour drive tomorrow, and meet some woman that I've been BS'ing with on MSN, If she's free for a few hours

yeah, drinking alone is usually not fun, unless your trying to accompish something, like, a lower intake gasket in -15 degrees Centegrade (5degrees Farenhite for the Americans out there who didn't pay attention in school

Glad that I'm home right now I'm swaping e-mails with a very atractive (In her pictures anyways) 25 year old local woman

I'm watching the Bears kick the bucs ass!!

I'm watching the Bears kick the bucs ass!!

SO how's the game, is your team winning and what's the score?

Do you think that this is relivant to the thread topic.

I think that I hyjacked LT's thread

lol we have an off topic thread guys.Lt won't like his thread getting hijacked.
http://www.automotiveforums.com/vbulletin/showthread.php?t=462418

BlazerLT, how is it going with the catch can? I just checked my can it was milky JUST like yours. I got the can sitting in warm water right now. It has been in the single digits(ferinhiet) her for about a week and a half.

BlazerLT, how is it going with the catch can? I just checked my can it was milky JUST like yours. I got the can sitting in warm water right now. It has been in the single digits(ferinhiet) her for about a week and a half.

You know what, the milkiness has gone away in the most part and there is no maore coolant caught in the catch can.

The milky stuff is just water from condensation from a cold engine mixed with fuel.

I have been chaecking the catchcan everyday now and it is just clear oil and nothing more.

The dexcool initially might have been from when I did a complete cooling system flush and some coolant got by the gasket somehow or the rad leaked a small amount into the oil cooler.

There is no coolant in the main oil and everything seems to be fine.

That's good to hear BLT, That's the best news that I've heard all day!

You know BlazerLT, i could probably back that up. I just checked the oil and it looks great. After letting the catchcan sit in warm water for awhile, I poured it on a white plate. NO RED DOTS. Just one small glob of water and the rest smelled like used oil. Checked the barf tank and coolant hasn't gone down. Kind of scared the hell out of me though when I saw the catch can. Especially after just doing the lower intake. Thought I would have to tear everything down again. I will keep an eye on my oil and catch can everday I drive it for the next couple of weeks or so. Hopefully it will go back to a normal dark color like yours. I feel better now knowing you are finding the same with yours.

You know BlazerLT, i could probably back that up. I just checked the oil and it looks great. After letting the catchcan sit in warm water for awhile, I poured it on a white plate. NO RED DOTS. Just one small glob of water and the rest smelled like used oil. Checked the barf tank and coolant hasn't gone down. Kind of scared the hell out of me though when I saw the catch can. Especially after just doing the lower intake. Thought I would have to tear everything down again. I will keep an eye on my oil and catch can everday I drive it for the next couple of weeks or so. Hopefully it will go back to a normal dark color like yours. I feel better now knowing you are finding the same with yours.

Just think, that crap would have been in your engine if you didn't have the catch installed.

I know. I keep thinking that. You saw the picture of my intake after I cleaned it in my other thread. That was a bitch to clean. I wouldn't want that crap back in there.

Yea, that is the condensation from the winter time and it will gum up your intake pretty fast.

That's good to hear BLT, That's the best news that I've heard all day!

Yea, I am glad I don't have to do this now. I might still do it this summer though and check my egr ports. I think one or both are clogged a bit.