Catalina 30 A4 engine

Dec 23, 2016
191
Catalina 27 Clinton CT
That exhaust pipe is galvanized and needs to be replaced. Catalina did that in the 70's. My 27 had the same thing. The pipe eventually was backing up the exhaust killing the engine every five minutes. Shut down the engine for a minute and it was fine. Also check your through hulls. Catalina put in gated valves in that era as well. The other thing you may want to do is replace the plate on the engine on the starter side. That plate sometimes lets go and leaks like swiss cheese, spraying water on the starter and altenator.
 
Jan 11, 2014
11,321
Sabre 362 113 Fair Haven, NY
That exhaust pipe is galvanized and needs to be replaced. Catalina did that in the 70's. My 27 had the same thing.
Sabre also built their own exhaust pipes out of standard 1 ¼" black iron pipe back in those days. Eventually they fail either by clogging or rusting out. The big box hardware stores have the pipe and fittings.
 

DArcy

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Feb 11, 2017
1,690
Islander Freeport 36 Ottawa
That galvanized exhaust looks better than mine did (after 43 years)


The exhaust flange came from Moyer Marine and the local plumbing supply store had the rest of parts I needed to put it back together. I did add fiberglass wrap after installing, which came from Amazon.
 
Feb 6, 2019
72
None None None
Hmm I just realized something about this A4. I don't see a heat exchanger? And its sitting in salt water. Uh-oh. A bit silly I didn't catch this earlier.
 
Feb 8, 2014
1,300
Columbia 36 Muskegon
A4's came stock as raw water cooled and any fresh water engines you see have an aftermarket kit. Moyer sells one.
My 5411 diesel had a similar kit. Extra impeller pump bolted on where the hydraulic pump would go on the tractor version and a head tank/heat exchanger.
 
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Mar 30, 2013
700
Allied Seawind MK II 32' Oologah Lake, Oklahoma
The raw water cooling isn't a problem with proper maintenance. There are thousands of the things running in salt water like that and have been for 4+ decades.
 
Feb 6, 2019
72
None None None
I'm very unfamiliar with raw water cooled engines. Every boat I've ever owned was fresh water cooled.. and just had risers that had to be serviced.

What are the potential failure points on a raw water cooled A4? Are we just talking something isolated like the exhaust manifold? Or the entire block?
 
Feb 6, 2019
72
None None None
Reading up on the subject... so yes, the raw water circulates through the block too. But the block steel is high in chrome nickel so the block can last decades of salt water exposure unlike something automotive. That's not to say A4 blocks are corrosion free...

The substitute A4 engine I found has a heat exchanger and all the parts for fresh water cooling. I won't have an opportunity to run it on a bench. Taking the guys word that it's operational.

I'm still reading on the subject but I may attempt to swap the A4 engines in the slip. While in the water.

Is there any reason this wouldn't work?
 

DArcy

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Feb 11, 2017
1,690
Islander Freeport 36 Ottawa
If you are considering the Volvo 2002 as a replacement, don't do it to save money. Parts for the A4 are cheap and the Volvo, well, it's a Volvo. If you want a more efficient engine to get more miles out of a tank it may be worth it but for casual use, the A4 is a better bet. Remember, that Volvo was pulled out of a boat for a reason and may have it's own issues.
In theory, swapping engines in the water is possible as long as you don't run into any problems with the prop shaft.
 

Mikem

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Dec 20, 2009
820
Hunter 466 Bremerton
I’ve had four sailboats and never had a Volvo...but two local diesel mechanics that do great work in our marina refuse to work on volvos. Parts seem hard to get and or identify due to frequent changes and they are expensive. This could be a Ford Chevy thing too. I heard once that Yanmar has 80% of the sailboat market. If true there must be good reasons.

I did have an A-4 in my first boat. Ran like a Swiss watch and was very quiet. More than once I hit the start button thinking it was not running when it was. It would push my Columbia 8.7 , 23’2” waterline, at 7kts. Took it from Newport, RI to Jacksonville, Fl.
 
Nov 22, 2011
1,192
Ericson 26-2 San Pedro, CA
I'm still reading on the subject but I may attempt to swap the A4 engines in the slip. While in the water.

Is there any reason this wouldn't work?
Absolutely no reason you cannot do this in the slip. People do it all the time. I have a mechanic friend who swapped an A4 in his Cal 34 by himself. With a friend
If you are considering the Volvo 2002 as a replacement, don't do it to save money. Parts for the A4 are cheap and the Volvo, well, it's a Volvo. If you want a more efficient engine to get more miles out of a tank it may be worth it but for casual use, the A4 is a better bet. Remember, that Volvo was pulled out of a boat for a reason and may have it's own issues.
In theory, swapping engines in the water is possible as long as you don't run into any problems with the prop shaft.
If he swaps one A4 for another A4 I don't see why there would be any issues with the prop shaft or anything else. It should be a drop-in replacement, easily done with the boat in the slip.
 
Jan 18, 2016
782
Catalina 387 Dana Point
I doubt I'd pony up $450 for that A4 unless it actually did run. They easy as pie to run on a test stand with gravity fed fuel.

The C-30 is a very easy boat to pull the motor out of - remove the galley counter above the engine, and hoist it out the companionway with the boom (use the main hyrd to support the boom at the point of lift)
 
Feb 6, 2019
72
None None None
I'm told it had 550 hrs on it. Taken out of a Catalina 27. The guy has told me multiple times that it ran a month ago before being removed. I asked him if anything was wrong with it.. He said no. I didn't ask why a perfectly good engine was removed.

It has a heat exchanger and he confirmed it was fresh water cooled. Only part missing is the raw water strainer.

I'm planning on hand turning it over to make sure it's not seized. Besides doing a bench test, is there anything else which would be an obvious red flag?

In theory, I should be able to do a compression test by hand cranking the engine - right? On the back of a truck bed. I've read that the A4 is designed to be hand cranked in the first place.
 
Feb 6, 2019
72
None None None
Hmm in theory, I should also be able to connect a battery with some jump cables.. and use the A4 starter to crank it on the ground or truck bed. Then test compression this way. There's a thumb trick on the plugs but I'd probably just use a meter.

Would this be safe for the motor?
 
Jan 18, 2016
782
Catalina 387 Dana Point
You are correct - the starter will turn the motor over fine just sitting on the ground or you can hand-crank it. If it has compression, you can almost always get it running.

I'm a big fan of electronic ignition on an A4 - more reliable than points and easier to deal with. Also an electric fuel pump instead of the stock mechanical one.

As said before - moyermarine.com for all things A4.
 
Feb 6, 2019
72
None None None
Did a compression test on the replacement A4... came to be about 120 in all cylinders! I decided to buy it.

There's an oil drain plug in the front of the engine, right? It leaked oil there as soon as I put it down.
 

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