Saturday, December 23, 2023

Rattle Can Rebuild Part 4

 As I go through the engine I'm looking for things that don't look right and it didn't take me long to find something.  The picture above is the raw water pump drive gear.  Basically, it's a gear that's driven off the crankshaft through a series of gears in the timing case and the slot in the middle is where the water pump impeller shaft inserts into.  The arrows in the picture show where the slot is gouged or worn from the water pump impeller shaft hitting it.  I'm not sure why this happened, but maybe it's normal wear for an engine with 974 hours.  

Fortunately, I have a new drive gear and bearing set, but I wasn't sure how to get at it.  The Westerbeke W27 schematic indicates that it is accessed by removing the timing case (or at least I thought it did).  The timing case is not something I want to get into, because in order to take it off, the govenor spring needs to be disconnected from the high pressure injection pump and it's accessed through a small plate on the side of the engine.  The manual states several CAUTIONS about how fiddly this is and if you drop the spring, you are screwed.  I'm certainly not a diesel mechanic, and warnings like that scare me.

I did a bunch of googling and forum posts asking around about how to get at the drive gear and because each engine does things a bit differently, I got a bunch of opinions that were all over the place.  Finally, I emailed the picture above to Hansen Marine Engineering and asked 1. Is this bad, 2. If so, how do I replace it.  Fortunately, they got back to me within a day and said this is a common problem and it should be replaced, but to do so simply requires removing the bearing housing that the raw water pump bolts to.  Yay, no timing cover removal!

With my newfound knowledge, I got to work and unbolted the bearing housing and within 5 minutes I had the old gear in hand.  To reinstall, I just had to seat the 2 interference fit bearings on either side of the gear.  Of course, you can just drop them on, they have to be pressed on.  I didn't really want to take it to a shop and I didn't want to hammer them on (and risk screwing up the bearings) so I tried a fun trick that I had used before when putting bearings on my tractor mowing deck spindle.

I put the gear in the freezer overnight and the next morning I heated up the oven to 275F and put the bearings in for an hour.  The theory is that the shaft of the drive gear will shrink slightly in the cold and the bearing races will expand with the heat.  Once everything was sufficiently hot and cold, I pulled the gear from the freezer and the bearings from the oven and with a hot mitt slipped them on.  One side slid on with little effort and the other side took a few taps from a plastic mallet on the inner race but it worked and once the temps equalized, the bearing were tightly fitted onto the gear. 

Now that the bearing and gear assembly was all together, reinstallation was just a matter of reinserting the gear and bearing housing assembly into the back of the timing case and bolting it back on with a gasket.  Super simple, but a lot of hand wringing along the way.  I might just become a diesel mechanic yet!

Next up, I assembled the actual raw water pump which consists of a housing (part #048080), the impeller shaft, 2 bearings, and a series of seals and washers to keep everything watertight.  Fortunately, the schematic is very good for this assembly so it wasn't difficult.  I still have to paint the pump housing, but once that's done I can bolt it onto the drive gear housing and call it a day.

Monday, December 18, 2023

Rattle Can Rebuild Part 3

As I said in a previous post, I'm probably doing this all backwards by starting at the bottom of the engine and working up, but I've made my bed and I'll be sleeping in it...  So, starting at the very bottom I began by pulling off the oil pan which showed some signs of leaking around the gasket.  Additionally, there was some rust on the bottom that I wanted to take care of before it got bad enough to leak.  

Fortunately, I didn't have a single one of the 17 oil pan bolts give me a hard time and they all came out without much of a fuss.  Getting the pan itself off was a bit of a challenge since it had probably been in place for close to 40 years.  Because the pan is sheet metal, I had to take care when getting it off so I took a 5" spackle knife and gently hammered it between the block and the pan around the whole perimeter.  I left a few bolts loosely in place in case it popped off too quickly for me to catch it.  Overall it wasn't too bad and took about 15 minutes to free it up.  The bottom of the pan had the last remnants of oil in it and I was pleased to see that I didn't find any metal shavings or anything but oil for that matter.

Once I had it off I cleaned up both mating surfaces with a razor blade and brake cleaner and had both surfaces nice and smooth within a half hour.  Next I removed the oil extraction hose and fitting and sanded the pan down and degreased the whole thing with more brake cleaner.  I'm sure it is toxic stuff, but brake cleaner does wonders on grease and grime.

Once everything was cleaned and prepped, I shot 3 coats of VHT high temp engine enamel primer and let it cure. The next day I did 3 coats of VHT high temp engine enamel.  I decided against using OEM Westerbeke red because:

  1. I had the VHT on hand and new cans (Chevy-Orange) are $18 at pretty much any auto parts store on the planet and are pretty close to Westerbeke Red
  2. OEM Westerbeke Red is $60 a can. The markup is insane and not worth it IMHO.
I gave the paint a few days to dry and cure and then installed a new banjo fitting and extractor hose to complete the job.  I also ordered new oil pan bolts from Westerbeke; for some reason their bolt prices are not quite as high as many of their other parts (probably because the same type can be purchased locally. I went with Westerbeke on this purchase because I didn't have to fiddle with pitch and size and could just click order; knowing that I would get exactly what I needed.

While I was waiting for parts to show up and paint to cure, I pulled off a bunch of other lower engine parts and cleaned up the block.  There was quite a bit of surface rust and took a wire wheel, steel brush and picks to clean it up. Once again, I followed up with a liberal dousing of brake cleaner and lots and lots of shop towels,   I went over it several times before I was satisfied that it was good enough.  

At this point I turned the rattle cans toward the engine and shot 3 coats of primer on the block and let that dry/cure overnight.  The next morning I went back and did 3 coats of Chevy-Orange to finish it all up. I let that cure overnight and then bolted the oil pan back in place along with one of the engine mounts that I had taken off and painted a few days before. To make sure the new gasket didn't slip while putting the pan back on, I put a thin layer of Permatex #2 on the pan and let it tack up before applying the gasket. I also coated each bolt in marine grade anti-sieze and torqued everything to spec. (I believe the oil pan bolts were 13mm with a torque spec of 57-64 ft/lbs).  Finally, I followed up with a quick wipe down of the bolts to remove any anti-sieze squeezeout and some paint to protect the bolt heads. 

Thursday, December 14, 2023

Rattle Can Rebuild Part 2

With the engine setup in the stand in my shop, I started tearing it down as much as I dared, taking lots of pictures along the way.  I have both the service manual and parts schematic on hand but the photos will really tie it all together once I started building it back up. 

The first order of business aside from photo documentation of all angles of the engine was to assess the condition.  Even though it only has 974 hours, it has been sitting in a garage for many years and there was a fair amount of rust, dirt, and chipped paint on the lower half.  I cleaned up as much as I could with a stiff wire brush and then hit all of the nuts and bolts with a liberal dose of PB Blaster to hopefully loosen up any rust that would prevent their removal.  

Somewhere along the way I decided to split the rebuild into 2 parts, mainly because of my fear of keeping the engine cantelevered on the bell housing in the stand and potentially cracking or deforming the housing (even though I keep the chain hoist tensioned).  The first part would be to get all the lower parts cleaned up, replaced, and painted and then move the engine back into the rolling dolly where it sits on its mounts.  The second part of the rebuild would be to do the same to the top half of the engine.  I'm probably doing it backwards because when I re-do the top half I'll get the bottom dirty again by virtue of gravity, but it is what it is, and I'll try to be careful and neat.

Along the way I found the following issues to address:

  • Fresh water cooling pump - appeared to have been leaking. Replace
  • Raw water pump drive gear - the slot where the water pump mates into is deformed. Replace
  • Front engine mounting bracket -  just all janky with rust. Clean and paint
  • Bottom of engine block - more janky rust. Clean and paint
  • Oil pan - leaky around the seal and want to replace the drain hose. Replace hose, clean and paint
  • Rear main seal - evidence of an oil leak behind the flywheel. Replace

The good news is that I think I have all the parts I need, but I've never dug this deep into a diesel before so I'm sure I'll be learning a lot along the way.  

Anyway, after letting all the bolts soak in PB Blaster for a few days I got started and removed the fresh water cooling pump.  I was able to crack the bolts without issue and had the pump off in a few minutes. However, when I looked into the hole behind the pump (inside the cylinder jacket) I could see a lot of rusty scale and old antifreeze sludge. Not good. I needed to get that all cleaned out before I put the new pump and cooling system back on because I don't want that circulating through the system.  Additionally, the rusty scale on the cylinder jacket probably keeps the engine from efficiently cooling.

I did some research and took a trip to the autoparts store and picked up a gallon of Evaporust. This is a chelating agent that basically bonds to rust and scale and puts it in solution.  I cut a piece of plexiglass, drilled bolt holes in to match the pump pattern and bolted it onto the engine where the pump used to fit.  Then I pulled off the thermostat housing (highest point of the fresh water cooling system in the engine) and poured Evaporust in until it filled up to the top and let it soak.

After two days, I pulled the petcock off the lower end of the engine and drained it all out. The result was pretty amazing (and disgusting).  I couldn't see any more rust and scale and all the sludge had miraculously disappeared.  The almost clear Evaporust solution that I had initially poured in was now a chunky jet black color.  I may have created a hazardous waste problem, but at least the inside of the engine is now clean.  I'll flush it all again once I have it put back together, but I'm pretty happy with the result. 

Sunday, December 3, 2023

Rattle Can Rebuild Part 1

Now that it's too cold to actually work on the boat effectively, I've turned my attention to the dreaded engine project.  I've had a love/hate relationship with inboard marine engines over the years, beginning in the 1980's when my dad had a boat with a Westerbeke W13. My dad had zero ability when it came to solving engine issues and left me in charge of making sure they worked.  The W13 was brand new and really didn't need anything but periodic maintenance, but we moved on to another boat with a Yanmar 3GM30 that was a bit long in the tooth and I was forced to spend a lot of quality time in uncomfortable positions trying to diagnose and fix issues along the way.  None of this put me off though because I always managed to find a solution and these small diesels were pretty reliable despite the hostile environment they lived in.  

It wasn't until we purchased a wreck of a boat (Pearson Ariel) with an Atomic 4 that almost never ran.  The good news was that it forced me to become a better sailor, the bad news was that it was always threatening to blow up (gasoline, not diesel) when the carburetor float would stick, overflow the bowl and start pouring into the bilge.  Even though it was the simplest inboard engine I've had, I never got comfortable with it and the boat didn't last very long.  

Since then, I've had a Westerbeke W21 that was super reliable, but prone to overheating because the old heat exchange had too much corrosion in it.  I pulled that apart several times fruitlessly attempting to clean out the heat exchanger and it wasn't until I was re-coring the decks on the Alberg 35 that I solved the issue by soaking it in some sort of acid solution for 2 weeks.  

As a result of my engine experiences over the years I have become somewhat distrustful of these beasts and the latest version (Westerbeke W27) is no exception,  However, I'm determined to get over this by tearing the engine down as much as I can so that I can understand exactly how it ticks.  I'm not going to open up the head because the compression tests prior and survey done prior to me buying the boat indicated no issues and it only has 974 hours on it (which is just a baby by diesel standards that routinely run for 5000 hours without a major rebuild).

The fun part of this project is that I have just about all new OEM parts and I will be replacing all the old parts with new ones (whether they are needed or not).  The big exception is the exhaust manifold which is no longer manufactured so I will be rebuilding that.  In addition to that, I'll be stripping down the engine as much as possible so I can repaint the block and get ahead of rust.

So, the existing engine cradle is pretty nice, but it's low to the ground and I can't access the oil pan and other low parts on the engine.  As a result, before I began any real work on the engine, I decided to get it mounted on an engine stand so I could get to the bottom parts of the engine.  

I ordered a chain hoist and engine stand from Amazon and shored up the shop ceiling joists with a 4x6 beam to carry the engine weight on the hoist and then lifted it up onto the stand.  Pretty easy to do, but a bit scary knowing that 430lbs could drop on my foot at any moment.  I was a little worried about cantelevering all the weight on the bell housing so even though it's mounted on the stand, I still keep the chain hoist hooked up so I don't put too much pressure on the bell housing.  

Now that i'ts mounted and everything accessible, the project can really begin. Stay tuned...