White Smoke Coming Out Of Sidepipe

[Mongoose930]

While I was driving home last night, I noticed white smoke coming out of my side pipe. I was a few miles from home and all of temperature readings and pressures looked good so I drove it the rest of the way home. Lots of white smoke under engine load and much less at idle or moderate load. I am suspecting a blown headgasket but I don't have a lot of experience with these engines and was wondering what else would cause this condition and what type of checklist I should go through to determine that it is indeed a blown headgasket. Assuming it is, I should probably plan on changing both gaskets while I am that deep into the engine? Any suggetions on head gaskets? I am leaning towards Cometic as I have had good luck with their products in the past. I am having a hard time choosing a gasket. The 428 bore is 4.132. I don't know if or how much my engine has been overbored but I am assuming .030 over. The bore options on the Cometic site are 4.08, 4.165, 4.25, 4.3 & 4.4. Which one should I choose? Also, there are many thickness options with .040" seeming to be the standard. I know I will need a new intake manifold gasket set which I already have. Should I replace the exhaust gaskets while I am at it? Would this be a good time to updgrade the head bolts to ARP or something similar? Obviously I will need new oil since the drivers side sidepipe had a nice concoction of anti-freeze and oil in it. Am I missing anything else other than a competent mechanic to help me out?

[Racer_X]

Definitely recommend Cometic head gaskets, change both sides. I'd change any gasket I touched while disassembling the top end, including exhaust. You might want copper exhaust gaskets for best sealing properties. The 4.165 at .040 thick is probably the one you want unless you wait until you pull the head and see exactly what is on the engine now. I'd also use ARP hardware wherever I could. You might run a compression check and leak down test to check all conditions before disassembly.

[Tom Cimino]

Before going too deep into the engine, check the intake gaskets. There has been many discussions on the failure of Fel-pro intake gaskets. Particulary the 1247 gasket set. The gaskets break down quickly for some reason. I have a pair of new 1247 gaskets hanging on a nail in my garage. So far, they haven't leaked. I doubt if they will as long as I let them hang on that nail. Instead I used Edelbrock intake gaskets, since I have Edelbrock heads and intake manifold. As far as head gaskets, most builders recommend Fel-pro 1020 head gaskets.

Standard bore on a 428 is 4.130. indicating your bore is only oversized by .002. If it has been bored .030, your bore would be 4.160.

[mickmate]

If you want to do a compression check before we tear it apart let me know. We can also pressure test the cooling system and check that for leaks. If you smell exhaust in the expansion tank or see it bubbling in there with it running and the thermostat open that means compression is leaking into the coolant.

[Gaz64]

The smoke is white or blue?

Auto or manual trans?

Which fluid are you losing?

Does the cooling system run at normal pressure, or lower or higher?

[blykins]

My money is on a failed intake gasket....more common on the FE engines, especially with the Felpro Printoseal gaskets.

[Mongoose930]

I am hoping it is a failed intake gasket as I have a new Cometic gasket ready to install due to an oil leak with the 2nd Felpo intake gasket in less than a year. I will take the manifold off to see what is going on before I order the head gaskets. Either way I am 90% through the job just to change the intake gasket.

[xb-60]

Originally Posted by Gaz64

The smoke is white or blue?

Good question. Oil smoke would be blue, but your's is white.
Do you have a brake power booster by any chance? Burned brake fluid is white.
Cheers,
Glen

[undy]

I'm with Brent, my bet's on the intake gasket. Fail-Pro strikes again...

[RICK LAKE]

Mongoose930 Before ripping the motor apart how about we do a couple of easy tests. Coolant pressure test to see if the system is holding. If not, looking at intake gasket and not having to pull heads off motor. Compression test and a leak down test will tell us alot about what is happened to the motor. I would also go with intake gaskets. Is there a milk shake look of the oil to start. Is the dipstick reading over filled with oil? Oil cap have a light brown or water on it? Just pull the valve covers and lets see what we have first. If there is some brown looking cream on the valve covers we have a coolant oil interaction. Might be just the intake gaskets or could be the head gaskets. This is the reason for compression and leak down tests. You want to compression number to be within 5-7% of low to high numbers. Leak down test you want to have about the same of 5-8% in all cylinders. If these numbers come out good, it's not likely to be a gasket for the head. Also at this point check all head bolts or studs for good torque reading. If everything checks out to this point, pull the intake. You said you are on the 2nd or 3rd intake gasket?? If so we need to look at the angles where the heads meet the manifold and where the bottom of the intake meets the block and check the angles. If anything was machined pass .005-.010" the angles could be too far off for proper sealing of this gasket after enough heat cycles. The other thing is how you install the gasket and what extra things are you doing. Heres a short list of what I do and have gotten 7 and now 8 years out of Fel-pro gaskets
Clean both surfaces, you know this. Check the angles with the intake dry on the heads and block do a light bolt down with 5-10 pound of torque on the bolts or nuts. Get a feeler gauge and you want less that .003-.005" to slide between the mating surfaces. This is for intake to heads only. If this is in spec, install gauges. If number is higher, how much? If you have over .010" This could be a sealing problem. If numbers are in spec, Get gaskets and spray 2 lite coats of Hi-TAC on both side of gaskets and let dry. Add a thin coat of GREY sealer to both top and bottom of gaskets and give it 3 minutes to skin. At this time put a nice bead on the motor block where the intake is going to rest. Install the intake gasket and make sure it's centered on all the ports and bolt holes. I know you are strong but need a 2nd person to install intake manifold to get an even drop down. Make sure the gasket don't slide down. Some guys use studs on one side of the motor to prevent this. Torque bolts or nuts in pattern from center out in 5-10ft pound incroments untill reach 30-35 torque reading. This sealer needs 24 hours before added fluids or running motor. This step is over looked many times and this can cause gasket failures. I use a Felpro 1247 gasket and got 7 years out of it and then rebuilt my motor to a 482 stroker that now has 8 years on it. The block, heads, and intake are all aluminum. The expansion rate is the same but more that an iron block, heads, and intake. Good luck, hoping it's the intake. Rick L.

[Mongoose930]

To answer the question on the smoke, it is definitely white. I do have a manual transmission - Tremec 3550. No power brakes. When I shut the car down when I got home, the sidepipe was leaking an oil / antifreeze mixture onto the garage floor.

With regards to the compression test, would it be safe to say that if the compression test looks good that the culprit is the intake maniford gasket and not the head gasket? I am not sure if I can get the intake manifold off without damaging the gasket to see is that is where the problem is.

I have a lot of family commitments today but I will try to get that valve cover off either tonight or tomorrow night to see what is there. I took the cap off of my expansion take and the level is low but I didn't detect any oil in there.

[Mongoose930]

Rick L - To be fair to Fel Pro, when I first bought the car, the original owner wanted to keep the dual quad set up and installed a new Blue Thunder manifold and Holley carb. Since he was selling the car, I am not sure how much care went into installing the new manifold as their was a significant leak in the middle of the rear rail. I really didn't want him fixing the problem so a second set of Fel Pros went in and after a few hundred miles, a leak developed in the same area. Tore it down again and puts lots of RTV in that area and had no problems. I developed a leak about a month ago that would only occur when I shut the car off. In the end, the intake gasket was leaking in the back corner of the block where the head meets the intake. I used and exacto knife to clean out the area and injected in a bit of RTV which has held so far. In the mean time, I ordered the Cometic intake gasket figuring I would install them when my patch failed. Looks like the time has come to but that set to good use. I appreciate your intallation advice.

[Barry_R]

You might want to carefully check the angles and fit of that intake relative to the heads. Just sayin'......

[vector1]

i would first do a leakdown test on all the cylinders and a coolant system pressure test which of course it should fail. if you had blown a head gasket to the degree it sounds you would probably notice some cooling system abnormalities, hoses coming off, excessive coolant filling the overflow bottle, etc. i would lean toward intake gasket failure, and as barry says, check your angles.

[olddog]

Before cranking the engine, pull the plugs and spin it. Make sure it doesn't have a cylinder full of liquid, or you may break something important. Then do your compression test.

[Mongoose930]

Thanks olddog - great suggestion. I don't want to make things worse!!!

[olddog]

Originally Posted by Mongoose930

Thanks olddog - great suggestion. I don't want to make things worse!!!

Your welcome.

Hopefully someone will mention something that keeps me from making my next mistake.

[tasman]

Good timing on this thread. I pulled home last week after a short shake out drive (the car had been sitting for a month due to electrical work) and when I stopped back home in the driveway huge amount of white smoke poured out of BOTH pipes. After parking I could see green oily fluid drip out of the driver side pipe and some fluid out of the passenger side pipe. I have not conducted the compression test / cooling test yet, but is there any reason I would have coolant in both pipes? Pulling the valve covers, I have water in both covers. It is an Edelbrock intake (and heads) without a crossover exhaust. The engine is 10 years since the rebuild and it is not driven much (standard transmission and no power brake).

Is there any specific scenario where I would have white smoke in both pipes?

Thanks.

[Racer_X]

Fel-pro intake gaskets probably sucked in.

[Mongoose930]

Hi Tasman,

I don't know what would cause coolant in both pipes at the same time but if you end up changing your intake gaskets, I would highly the FelPro Fel Pro 1247S3 from Survival Motorsports. The FelPro Printoseal gaskets failed after 3 months and so did the Cometic gaskets. The Felpro 1247S3 gaskets have a steel insert and I haven't lost a drop of oil or coolant since installing them this summer. I also used the Motrocraft TA-31 RTV which I purchased from Rock Auto. It has a nice grey color so if you do have a little squeeze out, it matches the aluminum color. Much easier to use than the Right Stuff IMO.

Hope you get to the bottom of it soon.