Friday, November 14, 2025

The Californian (or "There and Back Again")

If you get the reference, respect.

After the epic saga of Alice's engine refresh-turned-rebuild, I put a few hundred miles of joy on the odometer.  She ran great and I had no problems of any kind.  That, and the under-100-degree weather that blessed us in late September, led me to the conclusion that I could cross something off my bucket list - I would drive Alice to Carlsbad, CA and back.  I have a friend with a place out there and a group of us do Stupid Guy Things for a weekend every year.  this year was gonna be a lot of fun, and even more so since I got to drive a 50-year-old sports car.

I stocked up on supplies, including tools, coolant, water, an emergency fan belt, silicon hose mending tape, and a tire inflator and repair kit.  Early Friday morning, I gassed up and headed west, top down and ready to roll.

I got to a bit north of Gila Bend, AZ before I ran into a bit of rain passing by.  At 70 miles per hour, the rain washed over me and it was glorious.  It lasted about 15 minutes and dried up.  I was fortunate - that was the weekend the Valley got 2+ inches of rain.  I stopped in Gila Bend and wiped things down, namely the inside of the windscreen.  And then I was off again.

What a wonderful experience!  Alice cruises at 75 in overdrive.  The seats were comfy and the music was pumping.  I drove to Yuma, stopped for gas, then drove straight through to Carlsbad.

It got a little chilly in the mountains east of the CA coast, so I turned up the heat a little bit.  It turns out that I should not have done that.

I got to Carlsbad and pulled into the local supermarket parking lot, and I noticed that Alice was running a bit lumpily.  I shut her off and opened the bonnet...and was greeted by a blast of hot steam issuing from the heater control valve.  Coolant was leaking down onto the distributor and causing a short.  I shut the valve, but it did not stop leaking.  I got the radiator cap off (safely) and there was no coolant visible.

I think I was very fortunate to have made it to Carlsbad.  I did not see the temperature change at all, but I think I was on the edge of overheating.

So out came the tools!  I couldn't do anything about the valve itself, but I got that silicone host tape out and wrapped the valve to stop the dripping.  It worked.  I was able to refill with coolant and water (that I brought with me).  I ran without the radiator cap installed so the system didn't build pressure.  Since it was 70 degrees, I didn't worry about overheating.

I spent the next couple of hours thinking of how to do an in-field repair, or block off the valve... I came up with a plan, but rejected it as iffy (to block the header valve at the block and the hose at the heater).  I ended up calling a friend, who was able to overnight a used valve to me.  Thank you, George!

Saturday was awesome.  60 miles of open water jetskiing.  I was sore afterward.  Enough said.

I changed the heater valve in the parking lot of my hotel Sunday morning.  I bought a drip pan, and with a 7/16" wrench, a screwdriver and a razor blade I was able to save the gasket and swap the valve.  I wired it closed, refilled the system and started her up.  No leaks!

Here she is, enjoying the day.

The drive home was without incident.  I had the hood up (top to us Yanks) as it was a bit cool, and I wasn't going to use the heat.  It was a great drive - I was no sorer when I got home than when I got in the car in Carlsbad.

The MGB really is a great touring car with overdrive installed.  It handles well, is very comfortable, drives easily and gets decent mileage (27 MPG highway) to boot.  I'd do this drive again.  I probably will.

But let's talk about the aftermath.

I took the failed heater valve apart, and I saw this.


The diaphragm ripped crossways, and there was no way coolant was going to stay inside.

This is honestly a terrible design, the materials are of inferior quality, and the failure mode is to vent coolant.  These valves are notorious for failing even when nearly new - but mine really was new.  I did not expect this problem, but at least I was prepared.

So I said to myself, "Self... there has to be a better way."  And there is.  I found posts on the MG experience about adapting a ball valve (which even if it fails open, will not leak coolant).  I decided I was going to build one.  This is How I Did It.

First, I needed a valve.  The valve I used is a Four Seasons 74648 as recommended.  It is oriented similarly to the OEM valve, with one exception (that I will address later).  I found it on Amazon.

The valve has a threaded fitting where it will attach to the block, which meant I needed a base for it to thread into.  The OEM valve I had was useless now, so I cut off the flange and tapped it for the valve.  I used a 3/8" NPT pipe thread.  I had to grind down the threads where they protruded, but otherwise it was a perfect fit.


That part was easy!  The valve was correctly oriented to accept the cable and the output heater hose.  However, the valve actually opens the "wrong way" for a post-1974 MGB.  What is open should be closed and vice versa, so the control would operate backward.  The valve also would require a loop around the control instead of a cable stop. I wasn't going to let that slide.

I made an adapter out of 16 gauge sheet metal.  It attaches to the valve by virtue of the original attachment post and fingers to grab the little arm that moves the ball valve.  Here's a drawing of the shape and how to fold it to its final form.  Your mileage may vary - I am neither a machinist nor a draftsman.  The concept is valid, though.

The end result is that the cable attaches to the 'other end' of the valve with a cable stop, which now opens when I want it open and closes when I want it closed.  The throw on the valve is enough to get close to fully open and closed on the control in the dashboard.  It works.

Here it is, installed.


This valve should last a lifetime.



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Sunday, September 14, 2025

Engine, Engine, and More Engine

Gather round, y'all, and listen to my tale of woe.

Back in March, I came across someone selling a set of NOS high compression standard size pistons for the 18V engine (which Alice has).  I thought, "Wow, this would be a nice and simple and cheap upgrade."  (Note: there is no such thing.  We'll get to that.)  So I bought them.

I had not tinkered with the engine in any way, having records sowing it had been rebuilt back in 2001 and hardly any miles since then.  Alice ran fine and I had no reason to suspect any problems, so I left things alone aside from changing the timing chain to a duplex set (back in my transmission saga).  I didn't see any reason this couldn't go smoothly.  I also had been wanting to give Alice a bump up the performance ladder for a while.

Of course, I fell victim to the "while I'm here" trap and decided to splurge on a Piper 270 cam, lifters and springs.  We'll get to that too.

Since I wasn't doing anything serious (because replacing a cam and pistons isn't serious, right?), I decided to do the work in situ.

I won't bore with the details of removing stuff like the carbs, manifolds, radiator, and other sundry items.  Like hearts and kidneys, they're tinker toys.  Here's the removal of the head.


When I pulled the head, things didn't look too bad.  There was a ridge at the top of the bores, but I thought I could ream that out without much trouble.  The head itself looked okay, just dirty.  Two of the head studs did not want to come out - there had apparently been a little bit of a coolant seep that got into those studs.  I got them out cleanly, though, with some persuasion.

After a little cleaning, the head looked pretty decent.  I stripped the valves and wire brushed off a little carbon, and cleaned the surface.

Then it was cam time!  I pulled the front cover, tensioner and gears, and then the cam.  The original cam looked good with a little pitting on one lobe, but clearly not wiped.  The tappets looked good too.  I was optimistic.

From there it was time to get serious and pull the pan, and pistons with their connecting rods.  The pistons came out with a little difficulty because of that ridge, which should have been an omen but one I ignored.  The bearings looked okay with one major exception, where something had gotten caught and did a number on journal #2.  The crank itself looked okay and I found and cleared that one spot of whatever that had gotten caught.



So far so good, right?

I quickly learned that you can't just press the piston pins out - you either need bravery, equipment or access to someone that can do it for you.  I opted for #3 and had my friend Nate at Wild Child Classic Cars help me out by swapping to the new pistons.  We'll get back to him later, too.

I ordered new rod bearings (.010 undersize, as it had already been ground), and got to work installing the new pistons.  I honed the bores to get rid of the ridge (well, most of it) and got a nice cross hatch on the cylinder bores.  Things measured out just above standard which matched my paperwork.  The pistons went in easily, and then the cam did too.  I got everything put back together and after a couple of false starts by forgetting the distributor turns counter clockwise, got her started.


She started and ran well with good oil pressure.  I immediately noticed a ticking noise but it wasn't loud and I figured valves needed adjustment.  After break-in of the new cam, I went for a short drive.  Alice had some extra oomph, that's for sure!  But that ticking persisted, did not sound like valve lash, and I did not like it.

I had a problem with ticking in Gidget the Midget's motor, which ended up being me wiping the cam because of a bad valve guide / stuck lifter.  So I immediately became paranoid.  After consultation with Nate, I decided that things were not right enough to leave them alone.

Here's where the 'woe' begins.

I decided this time that I'd pull the motor and have Nate look everything over.  So out came the engine!  I left the transmission in the car, and that was not as unpleasant as I thought it would be.

Again, I'll leave the boring details of teardown to the imagination.  I pulled the clutch and flywheel (the clutch and pressure plate are good, like new).  Off came the head, again, and then the timing sprockets and chain, front plate, distributor drive and cam, then the oil pan and the pistons, the rear plate, the oil pump, and the crank.  There's a few steps in there I glossed over.  But I ended with a stripped block and a bunch of parts.

I bundled up the block (which when stripped, is only almost too heavy to lift into the back of a Kia Soul), crank, pistons/rods and head and shipped it off to Nate for analysis.  He came back with:

  1. The cylinder bores were a bit more worn than I thought.  And they were 'wavy', which means worn in some really odd way.  The ridge at the top of the bores was rather more pronounced.  He was surprised that the car ran as well as it did.  It was going to take an overbore to clean it up, likely .020 oversize.
  2. I had done a bit of damage to the crank when I installed the pistons, but he thought he could polish it out.
  3. The tappet bores were okay.  I bought a new set of tappets just to be sure I wasn't going to do any further damage.
  4. The head and block surfaces needed to be skimmed to make them properly flat.
  5. The head itself was fine otherwise, with no need for a valve job.
So I went searching for pistons, and amazingly found a net of NOS AE .020 pistons with rings.  I snapped them up and trundled them down to Nate's shop.

What I got back looked... beautiful.

Time to have fun!

First, the crank with new bearings (.010 mains), thrust washers, and an ARP bolt and stud kit.  She turned like butter.  Clearances were perfect.


Then in went the cam, and then the rear plate so I could put the engine on the stand.  From there, I installed the oil pump, and then the pistons and rods.  Well, not quite yet...

When I checked the gap on the piston rings, it was larger than I wanted (like .020 - .021 instead of .014).  That may not seem like a big deal, but it is the difference between an engine that will eventually blow oil and one that won't.  So I ordered a set of rings from Total Seal (conveniently located in the Valley of the Sun) and gapped them properly.  THEN I installed the pistons and rods, this time being very careful and using protection over the rod bolts.  Again, things turned like they were supposed to.  Not too tight, but not too loose either.

I changed the head over to double valve springs, which means I have a set of valve springs.  Changing them means changing the top and bottom caps as well.

The engine went back together uneventfully.  Generous amounts of assembly lube were used, of course, along with a Payen gasket set and a Lucas head gasket.  I got it back in the car with less trouble than I expected.


So I fired it up and everything was great.  Right?  Wrong.  I had no oil pressure!  Fortunately, I noticed this after only a short time running and shut things down.  I tried priming the oil pump repeatedly, but nothing worked.

I thought I was going to have to pull the engine again, but I decided to do a little investigative work first.  I pulled the pan and the oil pump to check it out and make sure it was okay.  The pump was fine.  The gasket was not.

One of these gaskets is the right one.  One is not.  Guess which one I used.  Fortunately I didn't appear to cook anything - bearings and cam looked fine.

I put the correct gasket on and reinstalled the pump.  This time, I got oil pressure after about 30 seconds of cranking.  And once I got her started for a new break-in run, I had 75psi of pressure.

Now life is good.  Alice has even more zip, runs quietly and well, and is back to being a happy car once again.

What did all this simple and quick upgrade cost me?  Too much.  I'd rather not say.  I like being married.  Let's just say over four figures were spent.  That doesn't include the oil cooler I installed along the way.

Wild Child saved my bacon, though.  Thanks, Nate and crew!  I expect to get many years of life out of this upgrade that turned into a complete rebuild.

Like Aesop, there is always a lesson at the end.  This one is, "Never try to take the quick way out.  In the end, it will take longer than if you hadn't."

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