I did a thing.

[MiataQuest]

How many miles are on the engine?

[— kung fu jesus —]

161,500

Going to do a LDT hot, compare the numbers. I'll make plans to R&R the HG. Not a big job, done it before.

[MiataQuest]

161,500 miles...

After you do the head gasket, maybe get another engine to refresh while you drive it.
-OR-
Ecotec swap!

[— kung fu jesus —]

Whoa, let's not get crazy.

More testing is needed. It's not horrible, but it's not great. I am having some contrasting results, so I need to eliminate some variables. A blown HG on this engine testing this healthy on 3/4 of the holes isn't the end of the world.

Here's what I know:

The radiator the car came with was newer and from an automatic (this car is a manual). Not surprising, but a cause for suspicion. The hoses were old. I believe the previous radiator may have busted.

The TB/WP had been changed at least once, as expected. I'm not certain the cam/crank seals were. I believe they were original, not uncommon.

While bleeding the cooling system, I saw a few small black flecks, which I believe were oil. Very small. Bleeding the car while idling for at least 20 mins, revving it produced bubbles. It *could* be the last of the air pockets, it could be air slipping past the HG into the coolant.

I did three coolant pressure tests. Two cold, one hot. Pressurized to 20 psi, I would lose 3 psi over 20 minutes. One test @20psi, It dropped to 15/16psi over one hour. No coolant on the ground, nor at the heater core.

I do not see any water in the oil.

I have driven the car about 50 miles since the TB/WP/Rad service and do not see any signs of oil in the coolant. I don't see any steam from the exhaust. I need to drive the car more to confirm.

The compression tests are showing some loss in cyl #2, the other three are really pretty healthy for this mileage.

The cold leak down test, the results were as expected, except #2. Hearing air between #2&#3 is a clue, but I did not notice any bubbles in the coolant, and I had the radiator cap off. I need to test again with a warm engine.

Here's the plan:

I will continue to drive it to see if conditions present themselves.

If it is the HG, I'll remove the head, look for cracks, check the block deck for square, take the head to be vacuum tested, fluxed, checked for warpage. If serviceable (most likely), I will skim it .020". I may have the intake manifold tanked to remove carbon while it's off.

I will purchase a Nippon Reinz HG kit and new head bolts. I will disassemble the valvetrain, change the valvestem seals, check the guides for play, reassemble, install, button up engine. Re-test. If it goes as normal, the motor will be a lot healthier with about a .5 compression bump.

2-3 days tops.

[HarryB]

Sounds like a plan; would not change a thing

[— kung fu jesus —]

Worst case, plan #2: dump in an NB2 engine sell off the BP4W engine to recoup costs. NB2 engines can be had locally between $650-800. NB1 engines sell for more.

[RustRat]

What about ECU? I mean, I am all in in what you do, love everything you’ve done in the interior, the attention to detail, but you’ll need an aftermarket ECU or an OEM NB2 ecu + keys, locks etc.


Sent from my iPhone using Tapatalk

[— kung fu jesus —]

Nope.

The NB2 engine here will run off the NB1 ECU. The VVT control can be operated with a Megasquirt VVT controller (https://www.diyautotune.com/support/...dware/vvtuner/) or left off/unplugged. Obviously, VVT control brings back some mid-range torque. I would likely keep the NB1 IM. All should be fine with the ECU, no codes.

[—Martin—]

IIRC the radiator from the auto trans cars have a little more capacity so that was a semi-popular upgrade back in the day.

[Midtenn86]

IIRC the radiator from the auto trans cars have a little more capacity so that was a semi-popular upgrade back in the day.

I have read that, but I've never seen a definitive answer on that. I think it maybe an assumption because it was common among other manufactures to do that. Most OEM style radiators come with the AT cooler fittings installed regardless of transmission option.

[— kung fu jesus —]

^that.

Even some new cars will come like that.

[— Agent☣Orange —]

Anything you want to tell us about?

http://www.dailymail.co.uk/news/arti...ing-moves.html

C1491748-95E7-4B25-AC42-BDD37A9415C6.jpeg A438E332-68FB-490D-9D66-EE3DB7B7AE2D.jpeg

[JamieH]

I think that's Super Jesus, not Kung-fu Jesus. There's a cape.

[— kung fu jesus —]

My style is to punch or kick the balls first. It makes an uppercut or knee strike more effective.

[— kung fu jesus —]

Drove around town today including some hard pulls on the freeway. No discernible flaws to report. Still not sure if it’s a HG issue. Will check coolant levels after it cools. Car runs really pretty good!

It has been unseasonably warm, so I have had to start yard work/spring cleanup earlier than usual. I don’t mind it.

Afterward, I gave it a much-needed bath with all the greasy fingerprints from me working on stuff.

I found a bottle of really strong wheel cleaner. It cleaned up these Advanti Storms really well.









Something interesting starting sinking into my brain...

My CSF radiator came wrapped in some decent 1/8” corrugated plastic. It is meant to protect the core in transport.



It was a shame to throw it out, so I had put it aside near my toolbox.

I started thinking that because it is cut the same length as the radiator, I *could* make a DIY radiator panel from it!

So I was looking at NB radiator panels last night, like this one from GarageStar:

https://garagestar.com/product/nb-ra...cooling-panel/

I think I can make this from the corrugated plastic.

I started making a few cuts and such, I may try using cardboard or paper first.



It’s ok if I mess this one up because there is another equally-sized piece that covered the other side.



More on that later. I still have some maintenance items to address.