Let's hear 'em. I just finished assembling my first shortblock (motor's not in yet, more stuff to do still) and I'm wondering what the most common mistakes have been around here. Stuck side seal? Pinched thrust bearing (already did that and caught it)? improperly installed oil or coolant seals? Timing issues?

 

a common one is when people use the wrong pulley and hub combo
those two has to be the same or that **** dont line up.

if you measured the seals to spec, you wil be fine with them not sticking... file them down if you have to.

coolant seal - as long as teh white marks on them are where they are suppose to be - and you didnt install them sideways or inside out or have one of them turned around, they will be fine

check end pay on it - dont have the gear for the CAS upside down...

 

https://www.rx7club.com/2nd-generation-non-technical-pictures-198/my-home-garage-t2-engine-build-791862/

 

ray I went through rebuilding the rew and when I reinstalled and had everything hooked up it made a a half of revolution and then locked. I had dropped a corner seal and never found
it, well I did find it later wedged. so a few new o rings and removal and reinstall Im back up.

The lesson is keep up with an inventory of all parts,

Johny

 

Be sure the tabs on the oil control ring springs are placed correctly, I did them twice to be sure. Although I pushed them in with my fingers and ended up slicing the crap out of my finger tips, they are razor sharp, be careful.

Motor fired up first try, ran flawlessly, but I put the clutch disk in backwards... so I couldn't drive it.. That was lame.

Rotate the engine by hand after the the build before you get it in the car.

Good Luck...

 

stock side seals and crushed front bearings oh and using T2 oil pump with na oil pump internals.The rotors inside the pump are different in size so the pump wont seal and you wont get any oil pressure.

 

My old crank pulley was sketchy. I called up Malloy Mazda (Ray Crowe) and I bought a brand new crank pulley/hub combo. I think it was $140--worth the peace of mind of guaranteed timing marks.

I'm hoping I did these right. I wanted every seal clearanced to .002" and came pretty close. I trashed (and replaced) six new seals in the process by over filing them , or under filing them then inserting them and having them break when I pulled them out.

i had the RA coolant seals, which I regret. They don't have the white paint, but I messed up one of them and bought a single OEM seal from the dealership. So I figured out how they go... the diagram isn't too hard to follow. I should have gone OEM outer with McMaster-Carr inner (I did do McMaster inner teflon seals).

yeah I pinched a thrust bearing and my endplay was 30 thousandths! but I got another one and now it's 1.75 thou. took me forever to figure out what exactly they meant by "chamfer edge down" or whatever, but I've got it now.

I dropped one but luckily I noticed it and got it back in place. I just turned the motor over with the spark plugs in yesterday and it seemed to be making strong and even compression sounds.

 

when i was measuring endplay i didn't know if additional spacers were needed so i thought i'll just buy them when i get to that part. well i ended up running short on time and ever nighted the spacers which cost me 27 bux to ship. not including buying a few spacers, so i can change endplay. that was an expensive few days.

 

i was pulling a apex seal out that was stuck. one side came up and my finger slid across it and cut my open. was pretty deep. alot of blood. damn apex seals are sharp

 

I overdid my sideseals a bit and was too much a n00b to care. Engine's still kickin' after 5 years and 45k but the compression has never been amazing (~95s on used but solid housings). Probably gonna get a proper tear down next winter.

 

I was bloody unorganized the entire time. Parts everywhere. Everytime I got to the next step I was running around the garage looking for a seal, or a gasket, or a spring, et cetera. Next engine I'll do perfect!

 

My biggest concern is always "Did both those apex springs seat right?" and "Did it click or not?"

 

with brand new apex seal springs there was no doubt in my mind when they were seating. the click was pretty loud

overdoing the sideseals sucks. I overdid 4 of them! they were still in spec but I wanted really tight tolerances. I ended up buying 18 side seals total.

 

I tried to get some custom work done on my rotors by carlos lopez, a year later and they still aren't done.

But my build went fine using some other rotors. The only downside is my buddy dropped the triangle part of the 2pc seal in the coolant chamber and it fell all the way down the motor. Sucked but a magnetic pick up did the trick.

 

I was building an engine with a friend and one of us accidentally dropped a corner seal into the engine. Didn't notice until it was fired up and mysteriously ran only on one rotor...

 

^ didn't you notice something was wrong when you turned it over by hand?

 

wow neat.

worst i've ever heard of, is two buddies built a motor. put in car, runs fine. lets go at like the top of 3rd gear.

they take it apart, and there are no bolts holding the oil pump on.

they got to do that point at each other "that was your job!" thing

pko and i did that with a drain plug once, motor was ok though

 

heres a couple from my first motor build and then rebuild.

I had the great idea to media blast my rotors. Afterwards the corner seals and side seals wouldnt fit in their lands. I spent hours hand sanding the lands in order to fit the seals properly.

Then when I put the motor together I build it on a dark porch while drinking beer and we missed the front oil dowel oring. When I started it up I got a nice little oil leak from my fresh built motor. Had to pull it, rebuild it and reinstall it in -10 degree weather.

 

Was your friend's name Aaron Cake? Lolz that sucks.

 

more horror stories please

 

lets see. the only bit of a horror story i have is putting the motor together and finding a corner seal was still sittin on the bench. nother better than tearing it down. then getting the coolant seals to stay in place. god what a bitch

 

I took a looong time to do mine. Watched the videos, measured and double checked everything. It started up first try and is running strong with a few hundred miles on it. My horror though is my oil pressure. Its terrible when the engines warm. I really dont wanna pull that front cover for a single o-ring.

 

Wow. 18. I usually get that perfect 0.002" side seal to corner seal clearance by simply moving the side seals around to different slots on the rotor.

 

yeah I didn't want to do that. At the time I was too concerned I would get something mixed up or make some stupid mistake. It worked out in the end though. I've had very little blowby on this motor. My catch can is collecting at most a teaspoon worth of oil every thousand miles.

 

I built my motor in the kitchen/nook of my previous place. Put half of it together on the floor, half of it on our brand new dining room table. (Still in the doghouse for that 3 years later) My measuring device took a ****, so.. i put it all together with minimal measuring (eyeball).

3 years later, and she's finally in the car and holding an idle. I've got 35+ pulses on all 6 faces.. 120+ psi on both rotors. Looking forward to loading the **** out of it and finding out what didn't hold together so well =).