454XLi exhaust manifold replacement 96 Carver 400

[hausherrs]

Hi

I have a '96 carver 400 with the 'little' big blocks. Crusader 7.4 XLI

I think these are the original 96 manifolds. And I got a hole in one or the gasket is shot. I dont know because i took ownership in 2016. I purchased two Crusader manifolds and elbows, bolts, gaskets, etc. Its the one under the couch so it didn't get much attention.

I need some advice on the port engine, the elbows / manifold closest (And i mean close) to the fuel tank. I already soaked the elbow bolts and nuts with PB blaster and anticipate breaking the bolts. I already put a 9/16 wrench in them and doubled up with a 3/4 wrench. Would not budge. I didn't want to go too far and ruin something before the PB had time to set in. All the old parts are going to the recycler.

Here are my plans:

1) Remove the fuel computer and mount
2) Remove and hoses and drain antifreeze into a bucket
3) Remove the elbows and loosen the exhaust pipe and disconnect

The next part I really don't want to mess up with a broken bolt in the head.

4) Remove the exhaust manifold.

#4 - What do you do for extracting the manifold? At this point I just have 8 bolts to remove. I cant see down there. But I just spray the manifold bolts with PB.

Any other bits of advise? Maybe warm it up a little and break them loose with a breaker bar? On the fittings that screw into the manifold is there something I need to use, other than Teflon, to seal it?

Thanks,

Steven

[km1125]

Too bad that it's probably too tight of a fit to get an electric impact gun in there. That would be an ideal tool to use.

Try tightening the bolts ever-so-slightly before you loosen them and do this again as you start to loosen... one turn loose, then go back in 1/4 turn, then back out 1 turn, then in 1/4, etc, until they feel like they're coming out easily.

Also can try using a hammer tapping on the end of a wrench as a poor man's impact gun. You don't have to hit real hard but it's better than putting a huge breaker bar and leaning on it with all your weight.


and always remember... lefty loosey, righty tighty. Particularly when you're trying to do something while upside down and backwards!

[mjk1040]

I saw a recent penetrating oil test and Liquid Wrench Penetrating Oil came out on top. Kroil penetrating oil came out #2, a product I thought was number 1! Getting engine up to operating temperature before trying to loosen bolts may help or warming up the cast parts with a good heat gun around the bolts may help too. I'd ask a good marine mechanic the tricks of the trade on this.

[hausherrs]

Thanks km and mjk.

I might see if I can get a Dewalt (Or the smallest I can find, with good ratings) cordless impact.

While at the store Ill check on the Liquid Wrench

I didnt get to work on it this weekend... We were going to take it out on the 4th to watch the fireworks from the bay when i noticed the "ticking" exhaust manifold. I have not found it yet, but it sounds and smells like its venting one cylinder into the cabin. But tonight I hope to at least get it off and cleaned up. Then do the other manifold/riser elbow in a week or two.

[hausherrs]

Update - I drained the coolant for the manifold and removed the riser bolts and nuts. One bolt broke off. Thats ok since I am replacing the manifold.

I also removed 5 of the manifold bolts from the head. Only 3 remain. I soaked it for 3 days with PB Blaster, reapplying it generously, 4 times. Ill soak it 1 or 2 more times today, heat gun it, pray that the last 3 come out without breaking, and try to wiggle them out with a breaker bar.

[bud37]

What kind of gaskets do they come with for the manifold to head joint...looks like nice stuff.

Don't forget ...new plugs while you can get to them easily.....

[hausherrs]

Thanks bud.

I try to get all original Crusader parts. Even the gaskets and this one looks like white thick paper. (Asbestos?)

On another note I got it down to one stinken bolt and it looks rounded off by the previous owner/mechanic I didn't even get a chance to brake it off! Its on #5 cylinder. You can see the hole in the pic right next to the "round" bolt. I think the best thing to do is get an air chisel and knock the head off then remove the manifold and bolt. If it was on anything other than a fiberglass boat I would weld a nut on it. But my gas tank is 6 inches away and I don't want to die.

In fact im a survivor. I got diagnosed with a huge benign brain tumor and had it removed. 5 weeks radiation and 14 months chemo. By the grace of God I'm still kicken'. As I said, I don't want to die, literally. but that's were I was when I stopped chatting on this forum for 2018.

Thanks

Steven

[bud37]

heh Steve...good for you, nice come back... .....they have some hardened sockets now that are made , or so they say to bite into rounded bolts........check the other ones and see if they are hardened. One left heh, isn't that always the way.....the last one gets me every time, I even started changing the removal order but no dice......good luck man..

No asbestos gaskets anymore as far as I know.....

[hausherrs]

I think these are the original 1996. They could be any carcinogenic material. FYI PB Blaster is carcinogenic according to California. I read the label. But so is used motor oil

[km1125]

You sure that's rounded off?? Looks like a 12 point bolt to me