One after the other, about to throw the towel

[mazpr]

First, it blew the oil pump and sending all the broken milled gears into the engine.

Then I ordered all brand new and send pay a machine shop to get it done right. The engine always leaked water and so it seemed the machine shop never checked for cracks and was charged for it.

I buddy sells me an alleged flywheel for BP and turns out to be from a Miata, complete different clearance, had to pull out the transmission.

Just today finished building the engine, and the brand new timing belt broke (seemed to be defective, did check for proper tension spinning freely), it bent almost all the valves on the exhaust side.

Before I forget, the Walbro fuel pump failed on me, had to buy a new one, and the Innovate wideband that arrived was defective, luckily under warranty and received a new one which is working fine.

I am almost to the point of completely giving up, this is insane...

[bogaut]

how did your valves bend just from a busted timing belt

[mazpr]

I have no idea, I am about to find out once I tear it apart. All four pistons are oriented toward the damper. It was idling smoothly, no problems, it started on the second to third try. I even let the car run while it was on the towers and went through all the gears. The car had no misfire, no bad idling, smooth mellow revs, with good vacuum 22, and oil pressure 50 psi.

Must say, the cylinder head was resurfaced a tad bit to remove imperfections from the old CH gasket, so not sure if that little bit of aluminum taken off was the cause. Its late, I am dying to work on the car, but got work tomorrow early in the morning, will report with any findings, and pictures if possible. I do have two spare cylinder heads and sets of valves and cams stores in the shed.

[atomicEGT]

what do you mean by "oriented toward the damper"? also, it would take like a LOT of material removed from the head for it to become an interference motor.

I don't know why the Miata flywheel didn't work for you, you can use a Miata clutch/flywheel without any issues as long as you use the correct throwout bearing...

[Mazda_Powered]

Yea, the Miata flywheel swaps right over, unless it was for a 1.6 then that could cause some ****...

Keep us posted on the exhaust valves, as that shouldn't have happened. Curious to see if you actually did some damage.

Sorry to hear about the bad luck so far

[KAinjection]

I dont even think mine is an interference engine with 10:1 pistons and .006" off the head and block. The pistons actually sit a ways below the deck on a BP and the cams on these engine are not exactly anything to write home about.

You need to do some checking on this thing. It would be impossible for almost every exhaust valve to be bent and not one intake valve. They didnt just all magically hang wide open when the belt broke and the engine kept spinning till it hit all of them. A timing belt does not just spontaneously break either. If in fact this did happen you have bigger problems.

Was the head reassembled incorrectly somehow and the valves dropped causing the engine to lock up and break the belt? Thats seems to be a more likely scenario.

I am using a Miata flywheel with a EGT/Protege pressure plate right now and it works fine.


Atomic I think he means the pistons were assembled with the mark toward the front of the engine. Damper = crank pulley

[mazpr]

Well, the Miata flywheel was off by a slight bit and would not disengage, making it impossible to shift at all.

How can I tell the difference between a 1.6 and a 1.8?

The clutch height mounts (in the Miata flywheel) are not the same height as the GT or LX flywheel. I will take some pictures, luckily I did not throw it away and have it in the shed as it is still in good condition.

I am about to tear open the CH, so will report with results and pics if possible.

[atomicEGT]

Yea, the Miata flywheel swaps right over, unless it was for a 1.6 then that could cause some ****...

not really, I was planning to use a 1.6 lightweight flywheel with a 1.6 clutch on an N/A motor build, it straight up doesn't matter as long as the clutch matches the flywheel and you use the correct TOB

Atomic I think he means the pistons were assembled with the mark toward the front of the engine. Damper = crank pulley

oh like I know what the damper is, I just thought he meant that like the valve reliefs or something were oriented the wrong way or something? **** if I know

Well, the Miata flywheel was off by a slight bit and would not disengage, making it impossible to shift at all.

How can I tell the difference between a 1.6 and a 1.8?

The clutch height mounts (in the Miata flywheel) are not the same height as the GT or LX flywheel. I will take some pictures, luckily I did not throw it away and have it in the shed as it is still in good condition.

I am about to tear open the CH, so will report with results and pics if possible.

1.6 flywheel and **** is smaller, like 200mm clutch disc vs 225 or whatever.

those stepped mounts for the pressure plate are totally the same height between the Miata and BP flywheel. the ones that are different are the B8 and BPT, I think?

[mazpr]

Here are some pics...

The valves, lifters, head cylinder gasket area is all in good condition. Premature failure of the exhaust cam notch, so the difficulty in turning was from the notch been gone, not because the valves were bent. Did shoot compressed air through the journal oil feed hole and passages were clear, no clogging or signs of oil obstruction to that area.

Exhaust cam journal is toast, CH is scrap metal. Everything else is good, I got another cylinder head, will swap tomorrow, and will continue to take more photos. Its late and back hurt a little.

[KAinjection]

That explains why the timing belt broke.

[nickz]

Any idear on how you fragged the oil pump?

[mazpr]

After the car sat for more than a year on a 1/4 of a tank with fuel stabilizer, it started within a few cranks.

Swapped CH, new timing belt (Duralast for now, $26.00), car is idling smoothly. Drove it around the neighborhood last night, LOL.

I blame the oil pump on two things, it was time for a new one and I had the infamous aluminum crank pulley. Everything is now with factory damper, factory flywheel (no lightened FW).

About the notches in the piston tops facing the crank pulley... So the valve relief on the top of the piston matches the correspoding I/E valves. I was just saying the proper clearance, piston to valve is set. Like stated, nothing happened to the valves or anything else, besides the cam and cam journal on ther CH. Will use it for spare parts, CH practicing and the usual JY core charge exchange.

Car is running smooth, sounds happy, fresh fuel and oil, and soon to install the MSII Extra (finally) sold by Stratified (if I recall its not a "real" MS).

I am glad, everything is together, no more chunks of pieces everywhere in the garage, room closet. No more a vehicle on towers with its cover.

Just been thinking back in time when the engine block was serviced by the machine shop and I opened a claim with the credit card. They still had my ch for cleaning and resurfacing, not sure if maliciously they slightly damaged it. Who knows? Could be just a bad batch, because I have seen other cams and must say those notches/guides for the gears are strong as can be.