***Blew a gasket again. updated with pics***

I was out on the water and I think I blew a gasket again on my 98 3.0L merc. However, unlike last time I did not lose any power. I will be taking off the manifold tonight to see if it's the manifold or the headgasket. My question is could the manifold gasket blow and still keep good power if it were the exhaust port? Also, if it is the head gasket what would cause my gaskets to keep going. I replaced the head gasket about 2 months ago.

Re: Blew a gasket again.

Re: Blew a gasket again.

macr6 said:

Also, if it is the head gasket what would cause my gaskets to keep going. I replaced the head gasket about 2 months ago.

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1. Warped Head
2. Warped Block
3. Both 1 and 2
4. Erosion of the block and or head from the prior head gasket blowing.
5. Improper torque and or torquing sequence on headbolts
Did you check the head and block for warpage?

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Re: Blew a gasket again.

and I think I blew a gasket again on my 98 3.0L merc.

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Ayuh,.......... What gives you That Idea,..??..??

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Re: Blew a gasket again.

Bond-o said:

Ayuh,.......... What gives you That Idea,..??..??

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I'm getting the same pfftt pfftt pfftt pfftt sound I was getting the last time I blew the head gasket, only this time I didn't lose power and it's seems a bit louder.

Re: Blew a gasket again.

Re: Blew a gasket again.

bomar76 said:

1. Warped Head
2. Warped Block
3. Both 1 and 2
4. Erosion of the block and or head from the prior head gasket blowing.
5. Improper torque and or torquing sequence on headbolts
Did you check the head and block for warpage?

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No I didn't check for warpage. It was the first time I was changing the gasket on an engine and didn't know I had to do that. I had it all put back together and the guy I was asking for help with, asked me the same thing. At least I know how to get it back apart and it shouldn't take me as much time this time.

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Re: Blew a gasket again.

I blew a head gasket on my '87 Cobra 3.0 a few years ago. Took the head to a machine shop to have it checked for true. They had to plane it when they found some slight warpage. Ain't had a problem since. Knock on wood.

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What's the Merc SN of your engine?
There was a Merc Service bulletin on 3.0L engines blowing head gaskets.

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Don S said:

What's the Merc SN of your engine?
There was a Merc Service bulletin on 3.0L engines blowing head gaskets.

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I'll have to check that out when I get home. Where would I find that SB?

Thanks for the help.

Also, anyone know roughly what it would cost me to get the head machined? I would take the head off myself and take it in.

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Re: Blew a gasket again.

Don't know about your area but I had a head from an old Oliver tractor (inline 6) planed this spring and the guy charged me 30 bucks. No teardown...just milling it back to a true, flat surface. If I remember right, I think 4 cyl heads and either side of a V6 or V8 were 20 bucks ea.

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Has it overheated at all in the past, even once?
That raises the prospect of a warped head way up.

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Re: Blew a gasket again.

wire2 said:

Has it overheated at all in the past, even once?
That raises the prospect of a warped head way up.

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Not since I have had it. But then again, when I got it and took it out for the first time it blew the head gasket after 45 min on the water. Changed out the gasket and tested the T-stat and it works. There is no telling if the previous owner had over heated though.

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Okay, here is the latest.

Don S - the serial number of my boat is 0L057999. That is what is listed on the flame arrestor. Is this one of the problem SNs? Where can I look that data up?

I took the manifold off and it wasn't that gasket. So I took off the head and the gasket was blown. Check out the pics. Also I made a HUGE ERROR I just don't know how big of mess I have gotten myself in. I didn't get the first cylinder to TDC. How bad have I hosed myself? I just forgot to do it cause I didn't think I was going to be removing the head tonight.

The gasket is blown in the same place it was the last time. I took some pictures of the gasket and the head and you can see on the gasket that it looks like it's warped right next to the tear. The head has this funny shaped wave in it (check the picture) that looks like where the gasket got warped.

My next step is to take the head and get it "turned". Then get replacement gaskets and put her back together.

Side note. If you check the pictures the 2nd cylinder looks like it has some white stuff on it right where the gasket blew. I was looking through some other threads and ppl were saying that is a sign of water in the engine. I am thinking that the water got in there from the gasket blowing this time cause when I changed it the first time, that cylinder wasn't like
that.

1st pic is of some of the white stuff in cylinder 2



2nd pic is of more of the white stuff with a better shot of cyl 2



3rd pic is of the gasket and the warped part.

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Re: Blew a gasket again.

I didn't get the first cylinder to TDC. How bad have I hosed myself? I just forgot to do it cause I didn't think I was going to be removing the head tonight.

You haven't hosed yourself yet! You go to TDC, (compression stroke) right before you put the distributor in, to ensure your firing on #1 on the dist. cap.
The white stuff is where water has turned to steam and cleaned the carbon off the piston.

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Re: Blew a gasket again.

Well, you are in the SN range for the Service Bulletin. Here it is.
Service Bulletin 98-14

Timing has probably been your biggest problem, but it isn't now..
As mentioned, the white stuff may be from water steam cleaning that area of the piston. But that is not the biggest problem.
Look at your piston some more. See what I see.
This happened because of timing.

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Re: Blew a gasket again.

Don,
That picture is very misleading as far as piston eat away. I went out this morning and looked at the piston again to make sure it didn't look like the picture. The piston is all there. I have a higher res pic at

http://hillfamilyweb.net/myimages/DSC_0114.JPG (click on the picture to make it large)

(it is still misleading but I just looked at it this a.m. and it's not eaten away.)

You can see that it isn't eaten away, that it is just the oil from me pulling the head off and dripping oil down in there. However, you can still see the ring in that picture but not because the piston is eaten away. Am I still hosed?

Thanks for your help so far Don and Daddy

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Lets see the Head,.........

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Re: Blew a gasket again.

Bond-o said:

Lets see the Head,.........

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I'll have to post those when I get home from work tonight. Something to look for on the head?

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Something to look for on the head?

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Ayuh,.......

Looking for Issues between the Block,+ Head surfaces..........

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Yea, I guess your ok, But it sure looked bad when I blew the picture up.
Looked like I could see part of the oil control ring center section. But the hi-res pic cleared that up.
Sure is nice to actually see and work on an engine when troubleshooting.

Re: ***Blew a gasket again. updated with pics***

What torque pattern are you using and what value torque for the head bolts?