So I put my engine back together. before I put the front cover and everything I tried turning over the engine. I put the rear flywheel nut and started turning with a wrench. I realized I was turning the opposite way. so started turning the right way. then I heard a cling/cracking noise. but nothing is catching or grinding. there is compression on all faces and by looking through the exhaust and intake I don't see any sctaches or gouge. is this the sound of apex seals ends breaking? I am really nervous. this the first time I am doing this .

 

If the apex seal corner pieces were glued to the main section of the apex seal it can be pretty audible when the glue releases. You're only spinning it over by hand, so there isnt much in the way of other noise to muffle it when it happens.

 

yea, the oem seals are already glued. I hope nothing has gone wrong.

 

I heard the sound of popping and cracking on my first build back in 2001 as I was tightening down the tension bolts and thought something had gone wrong. But that is a normal sound when apex seals are glued together for install and then you tension the stack and rotate the block, you can hear the springs pop the glued end piece off in the first few seconds.

As long as it turns smoothly you are fine.

 

Question: how long are glued Mazda apex seals? If they are longer than 80mm, they obviously will make that sound when you torque the tension bolts. But if they are a little shorter, they won't separate until the first startup.

 

I am not sure whether or not they use a jig to glue them, or if they just do it by eyeball. Either way, you not only have to consider their length, but also the spring tension.

It's good practice to rotate the engine immediately after building it, and within 5-6 rotations all the seals should have popped apart. For me, they usually pop apart as I am tensioning down the stack, and maybe 1 or two don't pop apart until I rotate it.

 

In case you haven't done so during assembly, you'd want top coat the plates and housings with a coat of heavy weight oil (20w50) to protect it on first dry start up.
I get a paper towel and soak in oil and rub down everything. If you have not done so and if on engine stand, rotate the motor and squirt some oil in there to coat the plates on both sides.
If you are premixing it'll inject upon crank BUT....just in case something isn't hooked up correctly it's a safe guard.

I usually rotate the motor a few times to get everything seated. Corner seals break off after few rotations.

 

In my opinion it's a bad idea to slather oil, grease, or vaseline all over the parts during assembly. You are likely to get it all over the coolant seals and contaminate the inner seal. Instead, I only coat the bearings with oil during assembly, and leave everything else bone dry. Once the stack is tensioned down and the coolant seals are seated and protected, you can fill the chambers with as much oil as you'd like to build initial compression and "protect the surfaces".

 

No, I don't mean when it's unassembled.
I mean as you start stacking the housing and plates.

 

most OEM seals are glued to be about 80.15mm in length, most reused housings after cleaning spec out to 79.96mm or thereabouts. so you can envision what is happening when you reuse old housings with new seals, although it is nothing to worry about.

i haven't used glued together seals in many many years(well occasionally i will but i will actually break the new OEM seals apart and install them differently) so i never hear that sound, it initially bothered me as well when i first heard it many moons ago.

 

Ever taken apart a healthy engine? Ever notice how little oil there is on everything, yet how even the coating is? That's what I strive for, and it works every time. Plus I don't smoke out my neighbors on first startup. My first startups are nearly smokeless. And you can put that in your pipe and smoke it!

 

It bothered me too until I started gluing them at 79.92mm. Problem solved.

 

Sorry, I don't smoke.

 

To add to this, once the engine is assembled and the front cover in place, you'll find the oil pump chain quite audible as well when you turn the engine by hand.

 

Ok cool. Thanks for the input people.

 

 

Lke the yellow and silver.

But I hate it when people paint gasket surfaces.

 

:p