Car a 1995 Volvo 850T

Last November I replaced my Head Gasket. After putting together the car, there was loud exhaust coming from the back of the engine. (Loud as if there was no exhaust manifold)

I shut the car off and proceed to remove the exhaust manifold and turbo hoping I didn't put it back right. I abandoned the repair for the winter.

Last week I started up again. Checked over the manifold, and turbo for any cracks or breaks. Put a mirror and looked for a notable cracked block. Checked for any gap or around between HG and block.

Put it back together and same results. Loud exhaust from rear of engine area.

When I put the head on back in November and followed the 3 step torque settings, doing the 130 degrees after the 44lbs, I didn't observe any creaking or anything.

So I'm looking for insight on what to do next. My thoughts are to remove the valve cover and cams, check torque settings. Double check with another torque wrench.

Or does this sound more like a cracked block?

I did use new head bolts (fcp) and had the head decked and leak tested

 

First thing I would do is a compression test. IF that comes out okay, I'd look for the exhaust manifold not being seated right on the block.

 

I'll get a compression tester.

I installed the exhaust manifold twice and had same results. And I put new gaskets on it.

I guess in the meantime (since I haven't put the heat shields back on) I'll start the car and try to feel for a leak. I didn't do that last time because I didn't want to wake my neighbors up with leaving the engine running.

 

Seafoam the motor, you will see where the smoke is coming out... there is your leak

 

ooooh....good idea Matty!

 

It is a good idea but my neighbors would flip out. I have a bottle of seafoam at home too.
Not only is the car loud, But to add smoke to it too.. even if the car is only on for a short time... lol

 

Why did you replace the head gasket ??
If you didn't have the noise before the gasket than it's more likely something in the first part of the exhaust system either isn't bolted tight, it's cracked or maybe the pipe developed a hole from being moved around.

Stuff something in the tailpipe like a few shop towels or something when it's running. The purpose is to make a restriction so the leak stands out more and then carefully run your hand around the manifold, turbo and downpipe areas ( I'd jack it up and look under too) to see if you can feel or see it. Maybe something that was rusted before you did the work last year wore through or popped open when you moved the exhaust parts around.

Seafoam is a great idea if you can get some help. Just don't use as much as you would to actually clean your engine, just enough to smoke a little !!

IMHO If you want help it's best to post a better question outlining the problem. People who have done head gaskets are more likely to open up a question about a head gasket or exhaust leak after replacing head gasket then they are to open something vague like yours.



Is it running fairly smoothly ??
If this is loud enough to bother you it's not very likely to be a head gasket or cracked head or anything to do with the head. Compression test would be definite proof either way.

 

I replaced it because the HG failed. Coolant was bubbling out and starting to overheat. It then started to blow white smoke out of the pipe. When I replaced the gasket it had holes in it.

Other than the noise the engine fires right up and idles fine.

In November when I ran it for a few minutes and then shut it off I could see smoke coming out from under the heat shield. I couldn't see if it was from the manifold or the hg area or from some other source.

I'll pick up a compression tester and also try the rags in the pipe. Currently I have the heat shields off so be able to see more.

 

When you first fire them up you're going to get smoke from all the stuff that was spilled taking it apart and used putting it together. Stuff like anti-seize, sealer, penetrating oil, antifreeze, etc .... so that's pretty common and nothing to really worry about.

What would be nice is if it was a bit colder where you'd get a lot of condensation (white smoke) out the tailpipe like a cold Minnesota morning. Might show that leak under the hood !!

 

ok I have a major leak around around the manifold turbo area. Its coming from the manifold side and not the turbo. I felt around where i could to see if there was another but didnt locate one.

When I had the manifold out before I checked for cracks but didnt see any.
So could a manifold warp (case iron) Can the exhaust port on the head be fubar? The head was at a shop and decked and tested.. Do they test exhaust ports as part of what they do?

One other thing. Is it normal for some of the manifold studs to be in the manifold and the others in the head.. I had like two or three like that.

I guess I should get a used exhaust manifold? Looks like I'll need to pull it apart again this weekend.

 

Pull it apart and put a straight edge on it. It's rare the manifold is going to warp of a sudden. If it is you can also have a shop machine it. Might want to compare machining to replacement.

If you were using the independent 5 exhaust manifold gasket set I'd be more inclined to think one slipped off or partially slipped off.

Good way to cheat is to use 3m weatherstrip adhesive on the manifold side. You glue the gaskets to the manifold, use some bolts to center each gasket and them when you go to put it on they are right there where they are supposed to be. Works great on transmission pans, differential covers and valve covers.

BUT ...... Glue it to the part that can be taken to the grinder to remove it later Don't glue it to the block, head or transmission as it's a bitch to get off.
I wouldn't recommend using it on aluminum either.

 

Are you sure the manifold gaskets were installed correctly? They will fit over the bolts more than one way, causing it to not seal around the port.

 

When I pulled mine, I put all of the studs back in the head before putting the head back on. Is it possible that the are not going into the head but allowing the nuts to turn down the studs without tightening on to the head?

 

Oh, question about seafoam... will seafoam smoke on a spotless head?

 

I'll probably do that. Since some were studs were not on the head it was a bit of a pita to push the gasket up put the bolt through.

I found a manifold for $40. So I'll probably pick it up, hopefully before the weekend. I guess taking it apart a 3rd time should be fairly quick now compared to the 1st time.. lol

I triple checked the on the second install since I thought that was the reason for the loud exhaust leak.

I torqued it to specs. Started in the middle and worked outward.

 

Seafoam will smoke on a brand new car, it smokes from being burnt off in the cyl..

 

For someone that claims to know as much about cars as you do, Im curious why you even asked this question... Dont get me wrong, I like your videos, but you really didnt know that putting something like Seafoam in the engine will cause smoke because of the Seafoam itself?

 

Part of doing any repair should include chasing threads. If you're doing head or block work it should be absolutely mandatory. Just because a bolt came out doesn't necessarily mean the threads are good.

You remove a component like a head, you chase every hole you can and blow it out with compressed air before any cleaning or machine work is done. The other thing to watch for is if you have something machined you may need to chamfer the hole a little so you are not pulling the threads up against the mating component.

If you've chased and blown out the holes you should be able to apply a little Loctite or anti-seize depending on application and thread that stud all the way in by hand. If you didn't chase the threads you should be able to see a stud that doesn't screw in as far as the others and you need to double nut the free threaded end and use a wrench to bring it home.


Little know fact:each cylinder exerts about 13,827 lbs. of pressure against the cylinder head at full throttle. In fact, head bolts may have to handle loads of more than 5 tons per bolt at wide-open throttle!

That's why your headgasket blew !!

 

Never used the stuff so I simply do not know. Did you have some expertise to add to Matt's answer, or are you just trying to look good? I don't post here to impress people, just help those that need it.

 

Finally someone else realizes this.

After bitching at me claiming he used to be a "PROFESSIONAL MECHANIC" and claiming I post "sideways information" and then blocking me before providing examples, he shows he doesn't know the name of R134a refrigerant, doesn't know what knock is, replaces his starter after not noticing a corroded positive cable, etc.