Starting Multiple Engine Upgrades

[ProjMan]

Indentified multiple upgrades and possible repairs on my 1980 CAT 30. Starting engine has gotten more difficult, exhaust leak, water has potentially fowled the glow plugs, engine is running hot. Based on my research I am diving into plenty of items. I plan to remove the cabinet over the engine to do a complete inspection. Expect to find the lift muffler inlet coupling has failed. Plan to unwrap exhaust riser piping to determine if replacement is required along with the new version hump hose. Plan to take the 2" heat exchanger apart and determine if it should be replaced with the 3" heat exchanger. I also plan to perform the Project: Glow Plugs which will include a starter solenoid. Of course with all that complete, the glow plugs, thermostat, antifreeze and oil will all be changed as well.

Does anybody want to discourage me?

Albert
New to sailing but learning fast

 

[Anonymous 121765]

Albert,
Welcome to the wonderful world of engine work. I have a 1980 cat & did a complete changeout a few yers back. You didn't say what engine you have but I assume from the heat exchanger it's a refit.

Actually once removing the cabinet, you will have ample space to work. I believe it was about 8 screws to detach after plumbing & exhaust is removed. Not that much of a bitch.

When doing mine, I was able to fix/improve alot of original stuff. If your new to this, It may be wise to have a certified mechanic come look at it and proceed on his recommendations. Past that, you have the opportunity to change all the hoses, some wiring etc. while your at it.

I have the 3m20a engine and thought the heat exchanger was not adequate for warm Florida waters. I contacted Sen-Dure(954.973.1260 was the tele. number at that time). They sent me a drawing which I marked up showing the connections and where I wanted them. I went with a 4 pass (3-1/8" OD shell). Now going thru passes which require top throttle, my internal temperature NEVER goes over 165 degrees.

If you carefully plan out your attack, it can be a "done right" job minus frustrations. Hope this helps,
CR

 

[Stu Jackson]

What engine?

If you have an M25, then you're going in the right direction.

Our Critical Upgrades Page could help: http://c34.org/bbs/index.php/topic,5078.0.html

As could our engine C34 Tech wiki: http://www.c34.org/wiki/index.php?title=Diesel_Engine

We put a 3 inch HX on our M-25 engine. It's great.

 

[ProjMan]

Had a good day. I don't think a novice can do enough research before getting into a project on a sailboat. It appears to be best to dive in. Had a good day attempting multiple removals. Broke a few plumbing parts that needed to be replaced anyway. Cut some wires that didn't need to be cut on a fan. Multiple small parts came out of the fan assembly. The fan was on a shelf assembly above the galley.

After I broke a few parts trying to get the galley off, I noted that there is a retrofit on the cabinet. A previous owner came up with a nice modification to be able to remove a corner section off the cabinet above the engine, remove the draws and then there is plenty of room to work on the engine.

I pulled the exhaust piping, heat exchanger and did a general inspection. After removing the exhaust piping insulation, and multiple layers of rust, I found the piping to be in surprising good condition. I took the heat exchanger end cap off for a closer inspection. Once again, to my surprise, there was no build up in the tubes and the pencil anode still had some size to it.

So here is the current plan. I am scheduling a mechanic to come on board and give me some recommendations. After all, I have done all the hard part. I still plan to rebuild the exhaust piping and replace the heat exchanger with a 3". Is it worth trying to use high temperature hose instead of hard pipe for the exhaust piping? Some of the links for this work recommend going to SS threaded pipe. What about dissimilar metals causing electrolysis between SS and malable iron?

Thanks for the extra links and encouragement.

 

[Stu Jackson]

More M25 exhaust riser details

Here's another link with pictures: http://c34.org/bbs/index.php/topic,5989.0.html

Is it worth trying to use high temperature hose instead of hard pipe for the exhaust piping? Some of the links for this work recommend going to SS threaded pipe. What about dissimilar metals causing electrolysis between SS and malable iron?

Don't do the hose. They make it with solid pipe for a good reason on ALL diesel engines I've ever seen. Ya gotta leave the flange with a pipe, then hose and then the nipple, so you have two susceptible joints and four hose clamps. Bad idea.

Yes, there are different materials folks have used for the pipes. Your boat, your choice. I used muffler pipe paste in the riser and the flange threads, which should provide some isolation and is good to avoid blow by past the threads.

Don't over think this, it's been done thousands of times before.

Just looking at the HX won't help. Take it off and shake it. If it sounds like a mariachi band... You also need to check for buildup on the intake port from the rw pump - salt drops out and blocks the port right there.

What's the mechanic gonna tell ya that you don't already seem to know?

 

[ProjMan]

OK. I didn't read enough before unbolting the riser pipe flange. So what kind of damage can antifreeze do to exposed parts?

I do have the M35. Any suggestions were to buy the heat exchanger? So far, pricing is around $700-$800. Ouch!

 

[Stu Jackson]

http://c34.org/bbs/index.php/topic,3744.0.html

I bought our 3 inch HX from a local Universal dealer for about $300 maybe six years ago, they can't have gone up that much since then.

 

[rbmcintire]

http://c34.org/bbs/index.php/topic,3744.0.html

I bought our 3 inch HX from a local Universal dealer for about $300 maybe six years ago, they can't have gone up that much since then.

Stu,
Did you modify your mounting bracket in any way when you upgraded to the 3" HX?

 

[Stu Jackson]

Yes, I had it bent down somewhat to be able to clear the exhaust riser, which on our boat goes aft, then up, then to port to underneath the head sink where the muffler is located. Good question. Thanks, I forgot to mention that.

 

[ProjMan]

I plan to remove the bracket for the exchanger, get a piece of 3" pipe to reshape the bracket. It also will need to be bent down to allow clearance for the exhaust flange.

Hope this helps!

 

[Stu Jackson]

For when you reinstall: put a piece of bicycle tubing or other insulation between the bracket and new HX.

 

[rbmcintire]

For when you reinstall: put a piece of bicycle tubing or other insulation between the bracket and new HX.

Here is a link to the Westerbeke/ Universal Service Bulletin on the 3" HX:

http://www.westerbeke.com/ServiceBulletins/sb_195.pdf

Just as ProjMan and Stu suggest, rework the bracket with a 3" dia. pipe and add sheet rubber to cushion the clamps. Thanks again guys. When we purchased our '84 last Feb., the surveyor said the mounting of our 3" HX needed improvement.

 

[ProjMan]

Galvanized Exhaust Lift Pipe

Is there any reason that the Exhaust lift pipe can not be made out of galvanized threaded pipe? Galvanized pipe should reduce corrosion inside and out. It should hold up to high temperatures as well.

As I reviewed the old threaded pipe, it is simple fittings and nipples: (2) 90 deg. Elbows, (1) 45 deg. elbow, (2) close nipples, (1) 6" nipple and some pipe high temperature thread sealant.

The remaining challenge is to take the engine flange and the brass wye off of the two ends of the piping.

After assembly, I plan to use header insulation tape on the piping.

Any comments

 

[Steve Walsh]

I rebuilt my Universal M-18 exhaust system 11 years ago with galvanized pipe from Home Depot. Still going strong with no leaks or apparent corrosion. I did re-install the pipe wrap insulation and check the pipe joints every year. So far, so good.

 

[Twice Around]

Albert,
I made my new hot section out of galvanized pipe a few years ago. It will off-gas A LOT more than black pipe, but I think that is the only drawback..maybe about 10-12 hours of really ventilating the cabin (hatches, engine room doors, etc.. open) was necessary.

 

[Old Skool Neil]

Hate to be the party pooper but constructing the hot section (before water injection) of galvanized pipe does not comply with the ABYC Section P-1 regarding exhausts.

Reference: http://www.ntsb.gov/Dockets/Marine/D...012/234864.pdf

Table 1 specifies allowable materials for exhaust systems. The dry exhaust list specifies aluminized steel, carbon steel, nickel-iron chrome and stainless steel. No galvanized steel, no brass, no bronze. The same materials apply to both gas and diesel engine installations.