Exhaust manifold removal

Engines, Shafts, Steering, Struts, Rudders, etc.
legendlc
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Re: Exhaust manifold removal

Postby legendlc » Wed May 15, 2019 8:02 pm

Another question..from the pics on the earlier post would the experts here recommend getting the head looked at while manifolds are off?
1978 37 Double Cabin
Lake Cumberland KY

Fastjeff
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Re: Exhaust manifold removal

Postby Fastjeff » Thu May 16, 2019 7:12 am

IF (God forbid) the block is cracked, you'll be able to see that with the intake manifold removed.

Did any of the block 'freeze out' plug push out?

Jeff
"We live at the bottom of an ocean of air, not at the top." General Marvage Slatington

legendlc
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Re: Exhaust manifold removal

Postby legendlc » Thu May 16, 2019 7:37 am

No all freeze plugs intact as far as I can tell. I've checked both sides of the block so unless I'm missing some then I think I'm good there. The engine that had the exhaust leaks also was very low on coolant in the heat exchanger when I inspected it. Just made me wonder if maybe the exhaust had been running low on water and it overheated and possibly blew a head gasket? I am still perplexed on the upper swivel riser and the water flow of it. There seems to be a stainless insert in the end going to the exhaust bellows and I am trying to determine if the water passage is the full circumference of the end or if there is casting material used to hold the insert in place? Mine I removed seemed to be in good shape but that is only if half the circumference is blocked by design. I tried rodding it out and drilling it but it won't budge. I am guessing it is not just rust buildup as it is solid and will snap a drill bit with ease lol.
1978 37 Double Cabin
Lake Cumberland KY

Fastjeff
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Re: Exhaust manifold removal

Postby Fastjeff » Fri May 17, 2019 5:58 am

I recommend you do a compression test. That will tell you a lot.

Jeff
"We live at the bottom of an ocean of air, not at the top." General Marvage Slatington

legendlc
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Re: Exhaust manifold removal

Postby legendlc » Fri May 17, 2019 8:10 am

Gat ya Jeff I was trying to figure out how deep to go before I button the exhaust back up. Sounds like it's time to start putting her back togeather and seeing what we have also following your earlier recommendation on running it and checking the oil at idle then with load. Thankfully there is a electric oil removal system it takes about 30 seconds to pump the oil out of the block so this part at least should be easy.
1978 37 Double Cabin
Lake Cumberland KY

legendlc
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Re: Exhaust manifold removal

Postby legendlc » Thu May 23, 2019 9:54 am

Jeff, are you talking about a cold or warm compression test I have head others say that cold compression test is useless? I am not sure. If warm then I will be needing to do some major work to get that far. Also another question is the exhaust manifold. The PO left a Felpro exhaust gasket on the boat but i am not certain if there is a difference between automotive and marine. This just says Chrysler 440 and is a one piece gasket. Looking online it appears everything I see for m440 engines are a gasket per port all separate??
1978 37 Double Cabin
Lake Cumberland KY

jralbert
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Re: Exhaust manifold removal

Postby jralbert » Thu May 23, 2019 3:50 pm

(in parentheses because you have to consider the source. But I remember being advised by the guy who surveyed my boat for me at purchase time putting a section in his 80 - yes, 80 - page report about compression testing. I am pretty sure he said only do a "wet" test.If I have the report I will post but it was more than 20 yrs ago so don't hold breath) [UPDATE: sorry, the report isn't in any of the three places I had hoped to find it]
-joel-
former owner 1988 '32 FB Sedan
Chesapeake Bay
twin 318 / 240 hp
Potomac MD

legendlc
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Re: Exhaust manifold removal

Postby legendlc » Thu May 23, 2019 5:56 pm

Yea I had heard that also but then also read in the wonder internet where everyone is correct lol that a dry/ cold test would help if your not up and running yet. Not sure. I am just trying to get this thing buttoned back up to see what I have. I have ordered most gaskets but still haven't located them for the block off spacer.
1978 37 Double Cabin
Lake Cumberland KY

seef158
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Re: Exhaust manifold removal

Postby seef158 » Thu May 23, 2019 7:24 pm

Compression test, doesn't matter much if it's cold or warm in my opinion. what you want to look for is one or more cylinders that vary greatly from the others, 10 percent or less differential is the rule of thumb.if they are all low squirt some penetrating oil in each cyl and test again. A scored cylinder wont come up much with some oil in it, dry or surface rusted cylinders will.
1972 28' express single 318, working on getting the bugs worked out.
forest lake, mn
Duluth, mn
Washburn, wi

legendlc
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Re: Exhaust manifold removal

Postby legendlc » Thu May 23, 2019 9:47 pm

I did a dry compression test originally and had 2 cylinders on one bank with vert low compression upon pulling the manifold it appeared those cylinders had water leak into the valves. It was very rusty as seen in pics earlier in this post. I wasn't sure if the valves had rust and not seating properly or if the gasket that did look very bad and looked torn on those cylinders but not sure.
1978 37 Double Cabin
Lake Cumberland KY