Jon Usle
September 25, 2022

Lawn Art Gets a New Engine

Thursday, October 29, 2020, was an exciting day.  My wife and I had just picked up Lawn Art, our PD-4104 bus conversion, at Leisure Coachworks in Fontana (see article in the July 2021 issue) and we were taking her home.  We were excited to try out all the new improvements made to our coach.  Our first camping experience was going to be on our private road.  We live in a rural area, so it would make the perfect practice location.

We were traveling north on Interstate 15 approaching the Lytle Creek exit when the bus started slowing down, and a major loss of power was happening.  My wife, who was driving, said she felt the engine shut down and immediately pulled the bus to the right shoulder.  All the gauges were in normal operating ranges, so it was a head-scratcher.  

After the bus was safely parked on the shoulder, I tried to troubleshoot the problem. We waited a few minutes and then tried to start the bus.  It would crank over but not catch and start.  So, I called our neighbor Jim, a retired aircraft and diesel mechanic.  He is just a phone call away whenever we have a bus engine problem.

Lawn Art’s ride home.
Lawn Art’s ride home.

Jim arrives 30 minutes later and the first thing he checks is the engine oil.  The oil is fine with no water in the oil.  We can’t access the water reservoir because on a PD-4104 it is above the radiator on the driver’s side, which was next to a very busy traffic lane.  Jim has us crank the engine over a few more times and it keeps turning over but not catching.  The engine compartment seems overly warm.  There are no liquids on the ground.  That is a good thing…right?

We are at a stalemate, so it was time to call a towing company.  We had no travel plans in the foreseeable future, so we hadn’t gotten around to renewing our Coach-Net membership, big mistake!  We called ten towing companies and heard every excuse under the sun.  It seems they didn’t want our money.  Jim calls another towing company called Aguilar’s.  They want our money and for only $750 will tow our bus the 17 miles to home.  After sitting on the side of the Interstate for five hours, we will take it.  Price is not an issue at this point.

Two hours later our tow truck arrives.  He was coming from only 20 miles away but encountered a couple of traffic collisions that delayed him.  After a quick briefing on the finer point of towing a PD-4104, air-line hookups for the air brakes are outside below the driver and in the engine compartment.  How long is your air hose?  Manual transmission, so thankfully, no driveshaft to pull.  

The tow truck driver then hooks it up, puts the bus in neutral, takes the parking brake off, and away we go.  We told the driver we would meet him at our exit, and he could follow us to our home.  He did an excellent job maneuvering his big rig tow truck and our bus on the rutted dirt roads to our house.  Ah, home at last.  We left Leisure Coachworks at about 3:30 PM and got home at 11:30 PM.  It would normally be a 45-minute to one-hour drive home from Fontana.

The next morning, I was out troubleshooting the engine compartment.  I found that the lower radiator hose had sprung a leak and all the water had drained from the cooling system.  I learned the hard way that a good rule of thumb is when you replace one hose, you replace all the hoses.  So off to Napa Auto Parts I go and buy new hoses, hose clamps, and antifreeze.

Straight on view of the corroded
thermostat housing.
Straight on view of the corroded thermostat housing.
A kitty litter type of corrosion happened to the thermostat housing.
A kitty litter type of corrosion happened to the thermostat housing.
Kitty litter corrosion in the cooling system.
Kitty litter corrosion in the cooling system.

When I started to remove the lower radiator hose, I found a kitty litter type of corrosion in the hose.  Then as I remove the rest of the radiator hoses, I am finding more and more of this odd sand-like substance.  Several radiator line pipe ends were corroded badly.  When I removed the hose from the thermostat, I found the sensors covered with this junk.  

With this stuff covering the sensors, the dash gauges would never have shown that the bus was losing coolant and beginning to overheat.  I cleaned and flushed as much of the sand from the coolant system as I could and put everything back together.  Then I added coolant and tried firing up the bus.  Please, start, please.  Nothing.  The motor was now seized up.

Water in the oil - Aww crap!
Water in the oil - Aww crap!
Aww Crap, a cracked head.
Aww Crap, a cracked head.

I checked the coolant again and it had drained somewhere.  I checked the oil and I found it.  Darn it.  I thought we had a blown head gasket.  I was wrong.  It was a cracked head.  I called and spoke with four different 2-stroke diesel mechanics on the west coast and got various quotes for the job.  All their prices were for cash.  I asked if they took plastic.  All four said no, cash only for parts and labor.  That put me off for a couple of weeks.  What were we going to do now?  I don’t want to sell or scrap the bus after we had so much work put into remodeling it.

When I thought all was lost, I got a message on Facebook Messenger asking me if I was still looking for a 2-stroke mechanic.  “Yes, do you know one?” was my answer.  I was given a number to call.  So, I called J&R Diesel in Riverside, California.  I talked with Dayle the owner of the shop and asked a ton of questions.  My favorite response was “Yes, we take plastic”.  

Their shop was currently busy with a couple of rebuilds and backlogged with other work so they would not be able to take us until March 2021.  It was October 2020 now.  That gave us about four months to skimp and save funds to get the process started.  We have pretty decent credit and got a credit card offer in the mail with no interest for 18 months.  Sure, why not.  We applied and got the card with an excellent high credit limit amount.  That card took most of the brunt for the engine work.

Fast forward to March 2021.  I contacted Aguilar’s Towing and schedule an appointment for a tow truck to pick up our bus and take it to the diesel shop in Riverside, 37 miles away.  They gave me a quote of $750.  Sold.  Talk about a deal.

The day came to take Lawn Art to J&R Diesel and Aguilar’s Towing brought a Lowboy trailer.  We loaded up Lawn Art and off we went.  When we get there, they tell us we are third in line.  No problem, the bus has no place to be until March 2022, so take your time.  If a quick cash job comes up, take care of them, and then get back to us.  Translation — things are cheaper if you are not in a rush.

The first thing J&R Diesel did was pull the head.  They found a crack.  Ok, how much is a replacement head?  $2000 plus $90 an hour for labor.  Ok, let’s get it done.  While it’s there, we might as well get the radiator serviced too.  Who knows how much of that “kitty litter” stuff is in the radiator?

That was followed by more bad news.  The top of the block had a catastrophic failure sometime before we bought our bus.  There was a gouge across the top of a couple of the cylinders.  The previous owner had a band-aid fix done to the engine.  They raised the piston sleeves up to meet the head for a better seat.  Reality check, we need the engine rebuilt.  What are we going to do?  (This is the second time this question has come up in the past six months.)

The shop tells us they can slap a new head on the old block if we want to go that route.  It was done in the past and worked until we lost that radiator hose and ended up cracking the head.  We love our bus, and we just got a bunch of work done at Leisure Coachworks, so we decided to do it right and replace the engine block too.  

Engine-transmission cradle removed.
Engine-transmission cradle removed.
Broken Water Manifold
Broken Water Manifold

The shop found a replacement block and will save all the good, reusable stuff from our old engine to build the new one.  The first phone call was “we need a water manifold, the old one broke when we were removing it from the head”.  What the heck is a water manifold?  I am a bus driver, and my knowledge of diesel engines had its limitations before this engine was rebuilt.  Some of that has now changed for the better.

Now, where do you find parts for a 1957 coach in 2021?  Bus friends!  I have been tracking all the surviving PD-4104s since 2012 and I have made a lot of friends, acquaintances, and contacts along the way.  I have a friend in Illinois by the name of Josh who has an RV repair business that is in the process of scrapping a couple of PD-4104s.  I hit him up and he has one, Ok what’s your PayPal account, and how much?  Called the shop and told them, got it.  Should be here in a couple of weeks.  Then it was, “Does your friend have any more parts?”  

We need:

A new radiator – our radiator was toast.  All that “kitty litter” plugged parts of the core solid.

A radiator top elbow – our old one was corroded beyond repair.

An oil cooler elbow – again corrosion issues.

Looks like the radiator ships on a pallet, got any storage bay doors? We need one particular size, he has it in stock.  Ok, what’s that PayPal account, and how much for these items?

The replacement engine block, all reusable items from the old engine, and replacement parts from Josh get placed in a hot tank for heavy-duty cleaning.  After they come out of the tank, the parts are pressure washed, then each item gets polished clean.  Polished?  Yes, our mechanic Dusty takes great pride in his work.  Every part looks new when it’s installed in our new engine.

Original Radiator, and Shroud.
Original Radiator, and Shroud.
Elbow top of the radiator.
Elbow top of the radiator.
Newly Rebuilt Radiator.
Newly Rebuilt Radiator.
Repaired radiator shroud by Leisure Coach Works.
Repaired radiator shroud by Leisure Coach Works.

The radiator shop took our old radiator and the replacement radiator and melded them into a new radiator.  The old radiator had tanks in better condition than the replacement radiator, but the replacement radiator had an almost brand-new core.

Also, our radiator shroud was toast, it was missing some pieces and we needed to either get a new one or get the old one repaired.  First, I call the usual suspects and post on the Facebook 4104 Group that I am looking for a radiator shroud.  Nobody has one in good condition, in fact, all of them are in worse condition than ours.  I called ten local sheet metal shops and none of them want our money.  The excuses were that the jobs were too small for them to make a profit and the shroud had too many angles for them to deal with.

Next, I contacted Vince Vasquez, he was our service manager at Leisure Coachworks to see if they may have a vendor that does sheet metal work and can make repairs to our radiator shroud.  He said maybe they could help.  They did more than help, they took our old radiator shroud, made repairs to it, and made it whole again.  I can’t say enough good things about Leisure Coachworks.  Their team is awesome, and I highly recommend them for any bus conversion or RV-related project.

After J&R Diesel pulled the engine from our bus, the engine cradle and engine compartment were cleaned and repainted.  Along the way in the rebuilding process, I was in constant communication with both Dayle and Dusty.  When they found something that probably could use a repair, I would drive by, or they would send me a photo.  After a decision was made, the part was repaired or replaced.

When the engine was almost complete, we ran into another problem.  I had found a replacement thermostat tank earlier in the rebuild, but it was deemed unusable.  So, I needed another part that no one had on the shelf anywhere.  I contacted another friend; Chris in Indiana and he works with MCI coaches.  I asked him if by chance he had the part I needed.  

He said he would check and called me back an hour later with the answer.  Yes.  Ok, what’s your PayPal account, and how much?  I see a pattern here.  The part arrived a week later.  Along the way, Dusty made a few changes to the engine.  He raised the oil fill location to a higher and easier access point on the engine and found me a spin-on oil filter to replace the canister oil filter that our original engine had.

Now our engine is complete.  The shop did a test start on the rack and even sent me a video of the start.  She fired right up.  They made a few adjustments and then the engine and transmission were placed on the engine cradle and installed back into the coach.

It’s now Friday, January 7, 2022, and it’s time for our engine break-in test drive.  Prior to our test drive, the mechanics at J&R inspected our air brake system along with checking and adjusting the brake pads.  The test drive ended up being 55 miles in length.  Chuck (my wife) climbed into the driver’s seat and Mike into the co-pilot seat.  Mike is one of the mechanics at J&R.  They then left the property for the long test drive.  

The first stop was a local truck stop to top off the fuel tank.  Then off they went.  City streets, highways, and freeways with an elevation gain of a couple of thousand feet.  The bus performed better than ever before.  It was traveling faster and had better power for hill climbing than the old engine.  All gauges and systems performed well.  

After the test drive, the bus was backed into the shop for some fine tuning such as the accelerator cable and a minor oil leak.  The accelerator cable was pulled, cleaned, and relubricated then reinstalled back into the bus.  It shifts so much better now.  Before taking Lawn Art home, I asked for a couple of last-minute things to be added to the coach:  air shocks on the engine tailgate and to add a handle to the tailgate for easier opening.

We picked up Lawn Art on Monday, February 7, 2022.  You might say 11 months for an engine rebuild is a long time, but it wasn’t that long.  Sometimes the delays were because they had a cash customer in a rush, cash is a priority.  Sometimes it was on our side waiting for 60-year-old parts to be found and shipped to the west coast.  

I learned a lot about diesel engines during our visits during the rebuilding process.  If you have a coach with a 2-stroke diesel and are looking for a go-to shop, I highly recommend J&R Diesel in Riverside, California.  Some shops only work on trucks, these guys only work on buses.

In our next article... Lawn Art takes her first post-rebuild shakedown trip.

Article written by Jon Usle

Jon Usle is 57 years old. At the age of 26, he purchased an old school bus to convert into a camper. Three months later, he and his wife became school bus drivers. Jon immersed himself in everything bus-related he could get his hands on, becoming a genuine Bus Nut. His knowledge of buses and bus operations opened many doors of opportunity and advancement. Jon worked his way up the ladder from bus driver to supervisor/trainer to general manager, through it all maintaining his Class B and school bus certificate.

In 2001, Jon stepped away from management to have more free time. He went back to driving school buses with his wife. When not “playing with buses,” Jon is an avid railfan. He also volunteers his time between rescuing and transporting Siberian Huskies and volunteering for his local search and rescue team.

Jon Usle can be reached at

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